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May 27, 2018
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https://www.sciencedaily.com/releases/2018/05/180527105806.htm
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Dolphin liberation in Korea
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"Dolphin liberation in South Korea has raised awareness towards the welfare of marine animals and has resulted in the strengthening of animal protection policies and the level of welfare."
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An engineering student, affiliated with UNIST has recently carried out a scientific investigation on dolphin liberation in South Korea. The paper presents the overall analysis of the social impact of the first case of dolphin rehabilitation in Asia, which occurred in 2013.This study has been carried out by Sejoon Kim in the School of Energy and Chemical Engineering in collaboration wit Professor Bradley Tatar in the Division of General Studies at UNIST. Their findings have been published in the April issue of the journal, "After the release of captive dolphins from South Korean marine parks, there has been a growing environmental movement towards the conservation and management of marine and coastal ecosystems," says Sejoon. "Although such movement relies on a single-species conservation focus and does not encompass an entire ecosystem, it has enormous symbolic significance for the welfare of marine animals."The research team hopes to expand their research to areas beyond the study of dolphin liberation and carry out in-depth case studies on various topics, including the whale-eating culture in Ulsan, the public perspective of dolphin shows, as well as the establishment of new types of dolphin life experience facilities.
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Endangered Animals
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May 24, 2018
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https://www.sciencedaily.com/releases/2018/05/180524141725.htm
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Imminent extinction of northern white rhinoceros motivates genetic recovery efforts
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Earlier this year, the last remaining male Northern White Rhinoceros (NWR) died in captivity, nearly cementing the fate of this subspecies for extinction. In the wild, continuing threats of poaching, habitat destruction, and small population size have contributed to the rhinos' status as critically endangered. Yet, novel conservation efforts that make use of cryopreserved genetic material could save the NWR, and other threatened species, from extinction.
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In a study published today in This work presents the first genome sequence of the NWR and thus the current, albeit limited, gene pool of this species. Tunstall and colleagues propose that this knowledge can help guide a tailored recovery program for the NWR. "Our study demonstrates the emerging role for whole-genome-sequencing analysis to evaluate the potential for population recovery," said Cynthia C. Steiner, who directed the study. Furthermore, advanced sequencing technologies, cryopreservation efforts like that of the San Diego Zoo Frozen Zoo, as well as novel reproductive strategies can be developed to improve recovery efforts for the NWR and other species that face similar threats of extinction. Recent efforts to this end are promising. The first pregnant SWR from artificial insemination has been reported by the San Diego Zoo Institute for Conservation Research, and it is hoped that surrogate SWR mothers may someday give birth to NWR progeny.
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Endangered Animals
| 2,018 |
May 24, 2018
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https://www.sciencedaily.com/releases/2018/05/180524112345.htm
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Facial recognition software could help endangered primates, slow illegal trafficking
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New facial recognition software and app invented at Michigan State University can help protect endangered primates -- more than 60 percent of which face extinction.
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Golden monkeys have lost so much habitat, they are only found in a handful of national parks in Africa; farming and illegal hardwood trade in Madagascar is gobbling up the island's forests and displacing native lemurs; in a recent six-year span, more than 22,200 great apes have been lost due to illegal trade, and yet there have been only 27 arrests."Intervention is necessary to halt and reverse these population declines," said Anil Jain, MSU Distinguished Professor of computer science and engineering and senior author on the study. "Automated facial recognition is one way we can help combat these loses."Jain and his doctoral student Debayan Deb harnessed the prowess of his world-renowned biometrics lab -- which has helped solve high-profile crimes -- to create PrimNet. The program uses convolutional neural networks, artificial-intelligence inspired technology that allows everything from self-driving cars to robots to observe and understand our world.The results, published online on the e-print service arXiv, show that in head-to-head comparisons, PrimNet outperformed state-of-the-art face recognition systems, including SphereFace, FaceNet and LemurFaceID (a predecessor of PrimNet that Jain's lab also invented).Along with improved accuracy, PrimNet represents a more cost-effective as well as a far less invasive approach to primate tracking. Traditional tracking devices can be expensive, ranging between $400 and $4,000. Capturing and tagging animals can be time-consuming and can adversely affect the animals. The process can disrupt social behavior, and it can cause stress, injury and sometimes even death.To complement PrimNet, the team of scientists created an Android app, PrimID. Researchers in the field can now snap a photo of a golden monkey, drop it into the app and identify the primate in question with a high degree of confidence.In many cases, PrimID will produce a match that's greater than 90 percent accurate. (With lemurs, PrimID scored an impressive 93.75 percent accuracy.) If it's not an "exact" match, the app will offer up to five potential candidates from the dataset, corresponding to the top five confidence ratings."We compared PrimID to our own benchmark primate recognition system and two, open-source human face recognition systems, and the performance of PrimNet was superior in verification one-to-one comparison and identification, or one-to-many comparisons, scenarios. Moving forward, we plan to enlarge our primate datasets, develop a primate face detector and share our efforts through open-source websites."This invention, along with sharing it open sourced, provides another tool to offset wildlife trafficking. For example, if a captured great ape can be photographed and identified, knowing its origin can offer insights to its capture and help improve efforts to deter future crimes.Additional MSU scientists who helped with this research, include: Debayan Deb, Sixue Gong, Yichun Shi and Cori Tymoszek. Susan Wiper, University of Chester (Great Britain), and Alexandra Russo, conservation biologist, also contributed to this study.The scientists would like to thank the Duke Lemur Center, the Dian Fossey Gorilla Fund International and the Rwanda Development Board for their support.
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Endangered Animals
| 2,018 |
May 23, 2018
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https://www.sciencedaily.com/releases/2018/05/180523131239.htm
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Orphaned elephants change where they live, in response to poaching and the need for food
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Young elephants who have lost either their mothers or the matriarchs of their herd are affected dramatically, and change where they live, according to new research from Save the Elephants and Colorado State University.
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The study, "Inter-generational change in African elephant range use is associated with poaching risk, primary productivity and adult mortality," is published May 23 in the journal By changing home ranges, these survivors alter their exposure to the risk of poaching and can better access green pasture, the study's authors said. This response across generations has important implications for elephants, as the spaces in which they live are increasingly squeezed by swelling human population, farmland and infrastructure.While most orphaned elephants that the researchers studied expanded their range into novel areas, others decide to "hunker down," and decreased the area over which they would typically range. One family that is well-known to researchers, the Swahili Ladies, abandoned rangeland that lay southwest of protected areas after poaching removed an entire generation of adults. This group then remained largely within the relatively limited confines of the protected area."Our study demonstrates that the loss of a matriarch can lead to dramatic shifts and expansions in the movements of some families, while making others much more faithful to the core of their original home range," said lead author Shifra Goldenberg, a postdoctoral researcher in Colorado State University's Department of Fish, Wildlife, and Conservation Biology, and a scientist with the nonprofit conservation organization Save the Elephants.The research team analyzed the movements of female elephants from nine different families over a 16-year period and found that nearly all of the elephants, including those that did not experience the loss of their matriarch, shifted ranges over time. When they shifted, they tended to move away from known poaching hotspots, and to areas with easier access to food. But the benefits of these shifts in location -- in terms of forage or safety -- varied."The ability to survive in the face of new human pressures is critical to the persistence of wildlife in the face of human global impacts," said senior author George Wittemyer, associate professor at Colorado State University and chairman of the Scientific Board of Save the Elephants."In elephants, we see a general ability to recognize high-risk areas and avoid them," Wittemyer added. "But range changes were exaggerated in families that had lost the mothers and leaders of their groups. The costs and benefits of these different types of responses is important to the population's ability to respond to emerging threats and recover from the effects of poaching elephants for ivory, which has reached the level of a serious crisis."
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Endangered Animals
| 2,018 |
May 23, 2018
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https://www.sciencedaily.com/releases/2018/05/180523091256.htm
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Long-term study reveals one invasive insect can change a forest bird community
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Eastern hemlock forests have been declining due to a non-native insect pest, the hemlock woolly adelgid. A new study from
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Pennsylvania State University's Matthew Toenies and colleagues analyzed a long-term response to the decline of eastern hemlocks using vegetation and bird abundance surveys. The researchers took advantage of surveys they had conducted in 2000 before adelgids had caused hemlock decline and compared those data to new data from the same forests in 2015-16, after decline. They then analyzed how both individual bird species and groups of species responded to this habitat change.The data showed that as hemlocks became less abundant in the forest, the bird species most associated with these trees also disappeared. As the hemlock-specific birds left, birds that are normally found in more general hardwood forests replaced them. Thus, biodiversity was reduced with the decline of hemlocks as well and the composition of the landscape became more similar over a larger area."Invasive species, climate change, and land-use change are all similar in that they make our world a less diverse place, and this study helps greatly in understanding how the loss of the eastern hemlock plays its own role in the degradation of biodiversity," adds University of Connecticut Professor Morgan Tingley, a community ecologist who was not involved in this research.Lead author Matthew Toenies says, "To sum up, to people who are saddened by the loss of hemlocks and the birds that rely on them, I would say one thing: We cannot turn back the clock -- we cannot un-introduce the hemlock woolly adelgid; but we absolutely possess the power to prevent this story from repeating itself."
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Endangered Animals
| 2,018 |
May 22, 2018
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https://www.sciencedaily.com/releases/2018/05/180522123327.htm
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First record of large-antlered muntjac in Vietnam
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In November 2017 -- under a biodiversity monitoring and assessment activity supported by the US Agency for International Development (USAID) -- scientists and conservationists of the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) and WWF-Vietnam captured photographs of one of the rarest and most threatened mammal species of Southeast Asia, the large-antlered muntjac (
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"It is amazing news," said Phan Tuan, Director of the Forest Protection Department of Quang Nam in Vietnam "The two individuals are both mature and of reproductive age. These images prove that the species still survives in Quang Nam province and give us hope that there might even be a breeding population."The large-antlered muntjac was discovered by scientists in 1994 and is found only in the Annamites mountain range bordering Vietnam and Lao People's Democratic Republic. Illegal hunting, mainly accomplished by the setting of wire snares, has decimated the species across its range. Snaring pressure is apparently high in the forests of central Vietnam. From 2011 to 2017, for example, government rangers and WWF Forest Guards removed more than a hundred thousand wire snares from the Thua Thien Hue and Quang Nam Saola Nature Reserves. In 2016, in response to the snare-driven decline of the species the status on the IUCN Red List of Threatened Species of the large-antlered muntjac was changed from Endangered to Critically Endangered.Conservation stakeholders are continuing efforts to protect large-antlered muntjac in the wild. However, in recognition of the overwhelming pressure that the species faces and the fact that its populations are now critically low, the government and international NGOs are planning to establish a captive insurance population for this species and the saola (Dr. Benjamin Rawson, the Conservation Director of WWF-Vietnam, notes: "Large-antlered muntjac do not currently exist in captivity, so if we lose them in the wild, we lose them forever. Scientists are racing against time to save the species. Addressing the snaring crisis to protect wildlife in the forests of central Vietnam and setting up captive assurance populations are vital if we are to succeed."In addition to large-antlered muntjac, other camera trap surveys funded by USAID also documented other conservation priority species including Owston's civet (The Leibniz-IZW and WWF-Vietnam survey teams are now expanding the systematic camera trapping plans to other areas in the region, including places with high biodiversity potential in the province of Thua Thien Hue, just north of Quang Nam. The teams hope to uncover more surprises. But regardless of what they find in the future, the re-discovery of the Large-antlered Muntjac from Quang Nam will always remain a milestone for the survey teams, for the conservation community, and for Vietnam.
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Endangered Animals
| 2,018 |
May 21, 2018
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https://www.sciencedaily.com/releases/2018/05/180521131832.htm
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Giant Chinese salamander is at least five distinct species, all heading toward extinction
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With individuals weighing in at more than 140 pounds, the critically endangered Chinese giant salamander is well known as the world's largest amphibian. But researchers reporting in the journal
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The discoveries highlight the importance of genetic assessments to properly identify the salamanders, the researchers say. It also suggests that the farming and release of giant salamanders back into the wild without any regard for their genetic differences is putting the salamanders' already dire future at even greater risk. In fact, some of the five newly identified species may already be extinct in the wild."We were not surprised to discover more than one species, as an earlier study suggested, but the extent of diversity -- perhaps up to eight species -- uncovered by the analyses sat us back in our chairs," says Jing Che from the Kunming Institute of Zoology, Chinese Academy of Sciences. "This was not expected.""The overexploitation of these incredible animals for human consumption has had a catastrophic effect on their numbers in the wild over an amazingly short time span," adds Samuel Turvey, from ZSL (Zoological Society of London. "Unless coordinated conservation measures are put in place as a matter of urgency, the future of the world's largest amphibian is in serious jeopardy."The researchers were surprised to learn just how much movement of salamanders has already occurred due to human intervention. Salamander farms have sought to "maximize variation" by exchanging salamanders from distant areas, without realizing they are in fact distinct species, Che explains. As a result, she says, wild populations may now be at risk of becoming locally maladapted due to hybridization across species boundaries.The researchers including Ya-Ping Zhang and Robert Murphy suspected Chinese giant salamanders might represent distinct species despite their similar appearances. That's because the salamanders inhabit three primary rivers in China, and several smaller ones, they explain. Each runs independently to sea.Given that giant salamanders can't move across the land, they suspected that salamanders living in different river systems might have had opportunity to diverge over time into what should now be recognized as distinct species. And, indeed, that's exactly what the genetic evidence now suggests.In the second study, Turvey and colleagues conducted field surveys and interviews from 2013 and 2016, in an effort that was possibly the largest wildlife survey ever conducted in China. The data revealed that populations of this once-widespread species are now critically depleted or extirpated across all surveyed areas of their range, and illegal poaching is widespread. The researchers were unable to confirm survival of wild salamanders at any survey site.While the harvesting of wild salamanders is already prohibited, the findings show that farming practices and existing conservation activities that treat all salamander populations as a single species are potentially doing great damage, the researchers say."Conservation strategies for the Chinese giant salamander require urgent updating," Che says. She says it is especially critical to reconsider the design of reserves to protect the salamanders and an effort that has already released thousands of farm-started baby salamanders back into the wild."Together with addressing wider pressures such as poaching for commercial farms and habitat loss, it's essential that suitable safeguards are put in place to protect the unique genetic lineage of these amazing animals," says Fang Yan, also at the Kunming Institute.
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Endangered Animals
| 2,018 |
May 18, 2018
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https://www.sciencedaily.com/releases/2018/05/180518102734.htm
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Asian tiger mosquito on the move
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Due to global trade and tourism, mosquitoes -- transmitters of dangerous infectious diseases -- have spread to almost every part of the world. Moreover, climate change promotes the spread of species that thrive under warmer temperatures even further. Scientists at the Goethe University and the Senckenberg Gesellschaft für Naturforschung have now compared the ecological niches of the Asian tiger mosquito and the yellow fever mosquito on various continents with the following result: "Due to its longer invasion time span of 300 to 400 years, the yellow fever mosquito has almost completely filled its niches in non-native areas, whereas the Asian tiger mosquito, with a shorter invasion time span of 30 to 40 years, has not yet arrived in all regions where they would find a suitable environment," says Prof. Sven Klimpel.
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"Over the next one to five decades, infectious diseases transmitted through vectors will increase" concludes Sven Klimpel's team at the Goethe University and the Senckenberg Gesellschaft für Naturforschung. Vectors transmit agents that cause infectious diseases from a host to another organism without contracting the disease themselves. Many known vector species are native to tropical and subtropical regions. If vector species are established in a new area together with a disease agent, the area of risk for the associated disease will expand correspondingly.Two prominent examples of vectors are the Asian tiger mosquito (The yellow fever mosquito, originally native to Africa, began to spread throughout the world 300 to 400 years ago -- presumably with the expansion of sugar cane plantations and slave trade. The tiger mosquito, which today is considered one of the 100 worst invasive species, originally comes from South and Southeast Asia. Over the past several decades, it has been introduced and spread by trade and tourism, especially by the trade of automobile tires and lucky bamboo (Dracaena spp.). For example, tiger mosquito eggs, larva and pupae were transported great distances by sea, surviving in small water puddles inside used automobile tires, or in water containers for lucky bamboo.In their study, the scientists investigated the ecological niches of both species in their native and non-native range, i.e., the totality of environmental conditions in which a species can occur. In their new ranges of distribution, mosquitoes can encounter different environmental conditions than in their native ranges. Invasive mosquito species are said to be especially quick to adapt to new climatic conditions. The scientists, however, found no evidence to support this. Both species occupy a broad niche and occur in a large number of different environmental conditions in their native ranges. Since similar climatic conditions prevail in the new distribution ranges, worldwide expansion cannot be explained by a niche expansion through adaptation, although local adaptation and genetic changes in species' traits cannot be ruled out.The scientists were, however, able to identify a difference between the two species: that time plays an important role in the expansion or invasion of a species. With its longer time span of invasion, the yellow fever mosquito almost completely fills its niche in the new, non-native distribution ranges; i.e. it occurs under many climatic conditions that also exist in its native distribution range.The Asian tiger mosquito is a different case. In the new distribution ranges, it does not (yet) occur in all habitats that offer suitable climatic conditions. The researchers therefore predict a further expansion potential for this species in the future. Klimpel sums up: "The Asian tiger mosquito can already be found in nearly all southern European countries, and due to its broad niche, it will inevitably spread and establish itself in northern Europe as well. Further exotic mosquito species such as
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Endangered Animals
| 2,018 |
May 18, 2018
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https://www.sciencedaily.com/releases/2018/05/180518102731.htm
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Giraffes surprise biologists yet again
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New research from the University of Bristol has highlighted how little we know about giraffe behaviour and ecology.
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It is commonly accepted that group sizes of animals increase when there is a risk of predation, since larger group sizes reduce the risk of individuals being killed, and there are 'many eyes' to spot any potential predation risk.Now, in the first study of its kind, Bristol PhD student Zoe Muller from the School of Biological Sciences has found that this is not true for giraffes, and that the size of giraffe groups is not influenced by the presence of predators.Zoe Muller said: "This is surprising, and highlights how little we know about even the most basic aspects of giraffe behaviour."This study investigates how the grouping behaviour of giraffes differed in response to numerous factors, such as predation risk, habitat type and the characteristics of individuals.Habitat type had some effect on group size, but the main effect on group size was in the behaviour of adult females, who were found to be in smaller groups when they had calves.This is contrary to another popular belief that female giraffes form large groups to communally care for their young -- this study, published this week in the Giraffe populations have declined by 40 percent in the last 30 years, and there are now thought to be fewer than 98,000 individuals remaining in the wild.In recognition of their drastic decline in the wild, they have recently been listed as "Vulnerable" on the International Union for Conservation in Nature's Red List of Threatened Species.However, conservation review is ongoing due to current debate over their taxonomic status, since some subspecies may be even more at risk of extinction than is currently recognised.Zoe Muller added: "This research adds another important piece to the puzzle of understanding how giraffes live in the wild."Giraffes are a threatened species, suffering ongoing decline across Africa, and this research highlights how they are actually an incredibly misunderstood species. We can only manage and conserve giraffe populations effectively if we properly understand their behaviour and ecology, which we are only just beginning to do."Despite their prominence, giraffes have been significantly understudied in comparison to other charismatic African mammals. "The common misconception is that giraffes are 'everywhere' in Africa, yet recent research efforts have highlighted the fragmented and rapidly declining nature of their populations."Their recent listing as 'Vulnerable' on the IUCN red list is a valuable step towards recognising their potential to become extinct, and more research is sorely needed to understand the threats and challenges they face in the wild."The next steps for this research will be to replicate the findings in other areas of Africa. This is one case study from East Africa, and more research is needed to see if the same effects are observed in other giraffe populations. Results can be used to understand how the management of habitats, environmental and social variables can support the conservation of giraffe populations.
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Endangered Animals
| 2,018 |
May 17, 2018
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https://www.sciencedaily.com/releases/2018/05/180517143641.htm
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Shocking study shows one third of world's protected areas degraded by human activities
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A shocking study in the journal
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The study is a reality check for nations striving to meet commitments under the Convention on Biological Diversity (CBD) to halt biodiversity loss through protected area creation. Since 1992, the global extent of protected areas has roughly doubled in size; more than 202,000 cover more than 15 percent of the world's terrestrial area, with a goal of at least 17 percent coverage by 2020.Though management objectives differ, ranging from strict biodiversity conservation areas to zones permitting certain human activities and sustainable resource extraction, the primary goal of all protected areas is to conserve nature.The authors looked at global "Human Footprint" maps to make their assessment which shows that 32.8 percent of protected land is highly degraded. For protected areas created before the CBD was ratified 1992, 55 percent have since experienced human pressure increases. The authors warn that CBD goals will be severely undermined if widespread human pressure continues inside protected areas.Said the paper's lead author, Kendall Jones of University of Queensland: "A well-run protected area network is essential in saving species. If we allow our protected area network to be degraded there is a no doubt biodiversity losses will be exacerbated."The study shows that governments are overestimating the space available for nature inside protected areas. Governments are claiming these places are protected for the sake of nature when in reality they aren't. It is a major reason why biodiversity is still in catastrophic decline, despite more and more land being 'protected'.However, the authors are not suggesting that high pressure protected areas be de-gazetted or defunded. To the contrary, it is crucial that nations recognize the profound conservation gains that can be realized by upgrading and restoring degraded protected areas while respecting the needs of local people.The most impacted protected areas were found in Asia, Europe, and Africa in places with massive human populations. But the study did find some good news: protected areas with strict biodiversity conservation objectives are subject to significantly lower levels of human pressure.Some of these least impacted protected areas include Keo Seima Wildlife Sanctuary in Cambodia, Madidi National Park in Bolivia, and Yasuni Biosphere Reserve in Ecuador -- places where WCS has made considerable conservation investments and therefore has successfully staved off degradation.Said Professor James Watson of WCS and University of Queensland, and the study's senior author: "We know protected areas work -- when well-funded, well-managed and well placed, they are extremely effective in halting the threats that cause biodiversity loss and ensure species return from the brink of extinction. There are also many protected areas that are still in good condition and protect the last strongholds of endangered species worldwide. The challenge is to improve the management of those protected areas that are most valuable for nature conservation to ensure they safeguard it."Protected areas are at the core of WCS's conservation strategy, as these are areas that are most effective at protecting natural ecosystems and their complement of biodiversity and ecosystem services -- over 80 percent of WCS's site-based field work takes place within or around protected areas. When well-managed (through sound enforcement, monitoring, clear boundaries) and funded appropriately, protected areas are effective in reducing the loss of natural habitat, and sustaining wildlife populations.Said Watson: "Most importantly we've got to recognize that these jewels in the crown need support- there are some protected areas that are safeguarding nature and that still haven't got any evidence of human encroachment in them. We must ensure these values are maintained."
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Endangered Animals
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May 17, 2018
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https://www.sciencedaily.com/releases/2018/05/180517143635.htm
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Limiting warming to 1.5 degree C would save majority of global species from climate change
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Limiting global warming to 1.5
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A new report published today in Species across the globe would benefit -- but particularly those in Southern Africa, the Amazon, Europe and Australia.Reducing the risk to insects is particularly important, the team say, because they are so vital for 'ecosystem services' such as pollinating crops and flowers, and being part of the food chain for other birds and animals.Previous research focused on quantifying the benefits of limiting warming to 2This is the first study to explore how limiting warming to 1.5Researchers at UEA and James Cook University in Australia studied some 115,000 species including 31,000 insects, 8,000 birds, 1,700 mammals, 1,800 reptiles, 1,000 amphibians and 71,000 plants in this, the largest scale study of its kind.Lead researcher Prof Rachel Warren, from the Tyndall Centre for Climate Change Research at UEA, said: "We wanted to see how different projected climate futures caused areas to become climatically unsuitable for the species living there."We measured the risks to biodiversity by counting the number of species projected to lose more than half their geographic range due to climate change."We found that achieving the ultimate goal of the Paris Agreement, to limit warming to 1.5"Insects are particularly sensitive to climate change. At 2"This is reduced to 6 per cent at 1.5"The current global warming trajectory, if countries meet their international pledges to reduce CO"This is really important because insects are vital to ecosystems and for humans. They pollinate crops and flowers, they provide food for higher-level organisms, they break down detritus, they maintain a balance in ecosystems by eating the leaves of plants, and they help recycle nutrients in the soil."We found that the three major groups of insects responsible for pollination are particularly sensitive to warming."If temperatures rise by 3The study includes the ability of species to reloCate to more suitable loCations as the world warms. Birds, mammals and butterflies have the greatest ability to disperse. The dispersal means that a small number of species can gain in range by 2100.Prof Warren added: "If warming is limited to 1.5Co-author Dr Jeff Price, also from UEA, added: "Examples of animals to really benefit from limiting warming to 1.5 include the critically endangered Black RhinoCeros, which is already highly threatened by poaching and habitat loss."There are also species which have been important in evolutionary theory and studied since the time of Charles Darwin, which would benefit from limiting warming to 1.5
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Endangered Animals
| 2,018 |
May 17, 2018
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https://www.sciencedaily.com/releases/2018/05/180517102230.htm
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The survival of sea birds affected by ocean cycles
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Several ocean cycles, such as the El Niño phenomenon, occur in the Pacific ocean and have climatic repercussions around the globe (e.g. intense rains in South America, mild winters in Canada, etc.) However El Niño (with a periodic oscillation of 2 to 7 years) is not the only natural and cyclical variation observed in the Pacific: the Pacific decadal oscillation (PDO) is a variation in surface water temperatures which causes significant changes in sardine and anchovy population sizes due to upwelling, a process in which nutrient-rich deep ocean water rises to the surface.
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In this study, researchers evaluated the impact of El Niño and the PDO on the survival of the Nazca booby, a tropical sea bird which nests in the Galapagos Islands and has a life expectancy of 15 years. This bird is a good model for the study of the effects of climate change on birds because it consumes resources (sardines, in particular) which are directly affected by climate variations. Using data from the long-term banding of the species between 1984 and 2012, the scientists discovered that survival rates among young Nazca boobies are very low during El Niño events because fish stocks -- in particular sardines, the bird's favourite food -- are low during these periods.Similarly, the survival of adult specimens is effected by the PDO. Researchers observed a higher mortality rate during warm phases of this cycle, despite their being conducive to the proliferation of sardines and thus easily accessible food. This unexpected correlation can be explained by greater reproduction difficulties: adults are thought to lose more energy in reproduction (less nest abandonment) to the detriment of their own survival. Inversely, during colder phases, such as the one occurring since 2008, adult survival improves because offspring mortality and nest abandonment allow them to recover more quickly.This study is a major breakthrough in what is known about the effects of climate change on sea birds. It shows for the first time the impact of long-cycle climate variation (in this case PDO) on the survival of a species, and could later be expanded to other species of sea birds in order to predict similar effects on these species.
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Endangered Animals
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May 17, 2018
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https://www.sciencedaily.com/releases/2018/05/180517081825.htm
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Climate-threatened animals unable to relocate
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Many of the European mammals whose habitat is being destroyed by climate change are not able to find new places to live elsewhere.
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30 of the 62 mammal species in the University of Exeter study will have their habitat substantially affected by climate change, but don't have the traits that could allow them to colonise a new habitat somewhere else in Europe.These included at-risk species such as the wolverine (classified as "vulnerable" in Europe), and others not classified as under threat, such as the Eurasian elk, the Iberian wild goat and the Pyrenean chamois.Most current assessments do not take account of climate change and species' ability to react, and the researchers say this means many species may be at greater risk than their official status shows."Some species that will need to move long distances due to climate change are simply not going to be able to," said senior author Dr Regan Early, of the Centre for Ecology and Conservation on Exeter's Penryn Campus in Cornwall."Unfortunately, many of the species most at risk from climate change are also will have the most difficulty in colonising new areas."The researchers studied two sets of characteristics to see how well each species could relocate to the places where climate will be suitable in the future.One important characteristic is whether the animals are "generalists" that can live in many kinds of habitats and eat a wide variety foods.The other important characteristic was the animal's reproductive strategy -- species that breed young and have many offspring have a better chance of establishing themselves in a new area.However, the complexities of climate change mean that some species -- even those that could move relatively long distances -- will struggle to move because possible new habitats are just too far from current ones.One example is the Western Mediterranean mouse, currently found in places including Spain and Portugal.Under predicted climate change, it may no longer be able to live in its current habitats, and might be better off in eastern Italy.But Dr Early points out it is "difficult" to see how the species would make such a move."If you look at the challenges of shifting ranges, you find that many species are a lot more threatened by climate change than we previously understood," said lead author Lisbeth Morrison."Even under lower estimates of climate change, we found really serious effects for many species."
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Endangered Animals
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May 16, 2018
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https://www.sciencedaily.com/releases/2018/05/180516172249.htm
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Diverse and abundant megafauna documented at new Atlantic US Marine National Monument
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Airborne marine biologists were dazzled by the diversity and abundance of large, unusual and sometimes endangered marine wildlife on a recent trip to the Northeast Canyons and Seamounts National Marine Monument, about 150 miles southeast of Cape Cod. Scientists with the Anderson Cabot Center for Ocean Life at the New England Aquarium observed dozens of dolphins mixing with schools of pilot whales plus more than a dozen of the very rarely seen and mysterious Sowerby's beaked whales. The researchers, aboard a twin engine airplane, also spotted endangered, Moby Dick-like sperm whales as well as the second largest species of sharks in the world and the bizarre-looking giant ocean sunfish or mola mola.
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The Northeast Canyons marine monument is a critical hotspot of biodiversity on the edge of the continental shelf where the shallow seas off of New England drop sharply into the deep waters of the northwestern Atlantic. In 2016, President Obama designated three underwater canyons that are deeper than the Grand Canyon, and four seamounts as tall as the Rockies, as the first American marine national monument in Atlantic waters. However in 2017, Secretary of the Interior Ryan Zinke recommended to President Trump that the Northeast Canyons and Seamounts either be downsized or eliminated. The exact nature of the recommendation has yet to be specified.Given the great distance offshore, documenting the marine life there is a challenge. During the 4.5-hour aerial survey, the team spotted 169 bottlenose dolphins, 57 pilot whales, 44 Risso's dolphin's, 13 rare Sowerby's beaked whales, four sperm whales, and 44 other dolphins of various species. In two sightings, they saw a mixed group of up to 50 bottlenose dolphins and 30 pilot whales, but what intrigued the researchers most was that three groups of Sowerby's beaked whales were spotted at the water's surface, a rare occurrence given their marathon dive timesThis is "extraordinary for such a small area," said Dr. Ester Quintana, the lead scientist on the Anderson Cabot Center aerial team, adding that they also observed basking sharks, the second largest species of shark in the world, and the strange, large, plankton-feeding Mola mola, or ocean sunfish.The aerial sightings help researchers understand how the species are using the richly biodiverse monument waters and deep coral canyons at different times of year and for different purposes. "One of the reasons we do this work is that we are just discovering what's going on out there," said Dr. Scott Kraus of the Anderson Cabot Center. "This is an opportunity to see how animals use this habitat. No one has ever done this before."This was the third in a series of aerial surveys of the monument that began in summer 2017, and the number of sightings by the scientists during this survey was higher than any other, nearly double the number of animals observed last fall."These surveys continue to show the incredible abundance of marine life in the Northeast Canyons and Seamounts Marine National Monument," said Kraus. "These sightings support the idea that this area is worthy of complete protection.""This area was declared protected because it is a fragile ecosystem with a wide diversity of corals, deep water fishes, and invertebrates around these pristine canyons and seamounts that support a vast array of whales, dolphins, and large fish," Dr. Quintana said. "As new policies recommend opening more waters off the US coast to offshore drilling, it is incredibly important to have areas that remain protected."She said the Northeast Canyons monument area is about one-tenth of one percent of all US ocean territorial waters. "Yet, the wildlife diversity we are seeing out there highlights the importance of preserving its ecological value," Dr. Quintana said.
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Endangered Animals
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May 16, 2018
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https://www.sciencedaily.com/releases/2018/05/180516172247.htm
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Climate change in Quebec equals a much greater diversity of species?
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A team of researchers believe that, paradoxically, climate change may result in Quebec's national and provincial parks becoming biodiversity refuges of continental importance as the variety of species present there increases. They used ecological niche modeling to calculate potential changes in the presence of 529 species in about 1/3 of the protected areas in southern Quebec almost all of which were under 50 km2 in size. Their results suggest that 50 to 80 years from now (between 2071-2100), close to half of the protected regions of southern Quebec may see a species turnover of greater than 80 percent.
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The research team, from l'Université du Québec à Rimouski, le Ministère des Forêts, de la Faune et des Parcs, and McGill University believe that, depending on the region, the gain in the number of species of birds, amphibians, trees, and vascular flowering plants could range from 12 and 530 %. It is the first study to examine in such details the potential effects of climate change on the biodiversity of a large network of northern protected areas.The researchers believe that the scale and rapidity of the species turnover will also result in a necessary reexamination of current conservation paradigms, since it will be impossible to preserve a snapshot of today's biodiversity in the National Parks. More specifically, the researchers believe that:1) Rather than trying to preserve current biodiversity in the National Parks, a more effective conservation strategy to ensure future biodiversity may be to preserve site resilience and a diversity of physical features and conditions.2) There will potentially be complicated choices ahead for managers of protected areas as increasing numbers of new immigrant species colonize protected sites. If historical communities are deeply modified, the managers may need self-sustaining populations of non-native species in some protected areas. But newly arriving species may also have negative impacts on ecosystem structure and function.3) Assigning conservation status to rare and recently naturalized species may prove a thorny issue, given that a significant portion of northern species are already at risk. But the conservation value of rare new species should be considered in a long-term continental perspective rather than short-term national perspective.4) It will be important to preserve and restore connectivity of protected areas to allow potential corridors for migration. In this way, species will avoid being trapped for decades or centuries between rapid retreat from the territory's southern edge and only a slow advance on the northern edge.The researchers caution, however, that potential species gains should not draw attention away from the potential extinction of local species that may no longer find suitable conditions in future in the protected areas where they are at the moment. The geographical pattern of potential relative species loss suggests that several species could disappear in both the southernmost protected areas of Quebec, and in the higher latitudes, where the extinction of only a few local species can have drastic effects on whole ecological communities.
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Endangered Animals
| 2,018 |
May 16, 2018
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https://www.sciencedaily.com/releases/2018/05/180516144836.htm
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Scientists predict how 686 marine species' habitats may shift in response to warming seas
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New predictions reveal how global warming may shift the geographic distribution of 686 marine species that inhabit North America's Atlantic and Pacific continental shelves, according to a study published May 16, 2018 in the open-access journal
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In response to warming seas, some marine species have already moved north or south to more favorable habitats, or to deeper, cooler waters. These changes pose challenges for resource management, such as conflicts over fisheries catch allocation between neighboring regions. Further shifts are expected, and predictions for individual species could help inform conservation and management efforts.To that end, Morley and colleagues used data from long-term ecological surveys to develop statistical models of thermally preferable habitats for each of 686 North American continental shelf species. Then, for each species, they applied 16 different ocean circulation models under future scenarios of low or high greenhouse gas emissions to see how their preferred habitat might change during the 21st century.The analysis predicted that climate change will alter the location and size of suitable habitats for many species, with all 16 circulation models projecting similar changes for two thirds of the 686 species. Habitats generally tended to shift north along the coastline in the model predictions, but these shifts varied depending on specific species' requirements, seafloor characteristics, and continental shelf width.The models predicted that the total area of some species' suitable habitat may increase, but habitats for other species, such as East Coast sheepshead, may shrink significantly. Species off the U.S. and Canadian West Coast may move the farthest, with some, such as West Coast canary rockfish, shifting over 1000 kilometers under a high greenhouse gas emissions scenario.The researchers note that their predictions do not account for finely detailed knowledge of every species, and the 16 circulation models disagreed strongly for about 20 percent of the species. However, unlike previous studies that focused on narrow geographic regions or took a low-resolution global approach, this study provided fine-grained analysis over a broad geographic range."We found a major effect of carbon emissions scenario on the magnitude of projected shifts in species habitat during the 21st century," says James Morley. "Under a high carbon emissions future we anticipate that many economically important species will expand into new regions and decline in areas of historic abundance."
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Endangered Animals
| 2,018 |
May 15, 2018
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https://www.sciencedaily.com/releases/2018/05/180515081712.htm
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Wildfires may cause long-term health problems for endangered orangutans
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Orangutans, already critically endangered due to habitat loss from logging and large-scale farming, may face another threat in the form of smoke from natural and human-caused fires, a Rutgers University-New Brunswick study finds.
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The study appears in the journal In 2015, Wendy Erb, a postdoctoral researcher in the Department of Anthropology at Rutgers, was studying male orangutans in the forests of Indonesian Borneo when fires started. She and her colleagues at the Tuanan Orangutan Research Station continued working until they had to stop and help fight the blazes, which occur annually, often due to smallholder farmers and plantations clearing forests to plant crops.A few weeks into the fire season, Erb noticed a difference in the sound of the males' "long call," which scientists believe is used to attract females and warn other males. "I thought they sounded raggedy, a little like humans who smoke a lot," she said.Erb decided to find out if the smoke the orangutans inhaled during the fires had affected their health. Humans who inhale smoke suffer ill effects, but she knew of no studies on the possible effects on orangutans.Erb studied four "flanged" males, who weigh about 200 pounds and have large cheek pads. She awoke each day before dawn to collect their urine in a bag at the end of a stick she held below them. Analyzing their behavior and urine, the scientists discovered the big males traveled less, rested more and consumed more calories. They also produced more ketone bodies, molecules made by the liver from fatty acids during periods of low food intake, which was unexpected because the apes were eating more, not less. Why were they burning fat?The only new element in the orangutans' lives was the three months of fire and smoke. The forests' natural surface consists of peat, which is flammable, allowing the fires to burn underground for weeks. The fires were worse in 2015 because of a strong El Niño effect, which brought with it a severe drought.Soil analyses suggest that wildfires have occurred in Borneo for millennia, but have become increasingly frequent and intense in recent decades due to deforestation and draining of peatlands. In 2015, Indonesia experienced the most severe fire activity and smoke pollution on record since the disastrous wildfires during the 1997 El Niño droughts burned some 24,000 square kilometers of peatlands (12 percent of the total peat area). Peatland fires destroy forest habitats, release greenhouse gases and produce hazardous particulate matter, the leading cause of worldwide pollution-related mortality. Two independent studies estimated that the 2015 haze caused somewhere between 12,000 and 100,000 premature human deaths, but there has been very little research into the effects on wildlife populations inhabiting these burning habitats.The unexpected loss of nearly 100,000 Bornean orangutans from intact forests in Kalimantan between 1999 and 2015 indicates that habitat loss alone is not driving this critically endangered species' declines. Increasingly frequent exposure to toxic smoke could have severe consequences for orangutans, other animals and people, and this research highlights the urgent need to understand the long-term and indirect impacts of Indonesia's peatland fires, beyond the immediate loss of forests and their inhabitants.Anthropology professor Erin Vogel, co-author of the study and the Tuanan Research Station's co-director, said the next step is to analyze data from female and juvenile orangutans to see how the fires affected their health."We'll look at different indicators of inflammation in the urine," she said. "We'll look for cytokines, proteins that are part of the immune response, and cortisol, a hormone associated with stress. It's possible these males are burning fat because their energy is going to repairing tissue."
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Endangered Animals
| 2,018 |
May 14, 2018
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https://www.sciencedaily.com/releases/2018/05/180514095509.htm
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Rhino horn used to comfort the terminally ill in Vietnam
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From treating cancer and erectile dysfunction to managing hangovers, the horns of endangered wild rhinoceros are widely used as a medical cure-all in parts of Asia. A new Danish-Vietnamese study from the University of Copenhagen uncovers new reasons for why Vietnamese consumers buy illegal rhino horn. This knowledge can now be used in campaigns to save endangered rhinoceros.
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The World Wildlife Fund (WWF) estimates that 1,054 rhino were killed by poachers in South Africa in 2016 and the worldwide number of rhinos remaining is estimated to be 30,000.A new study conducted by the Department of Food and Resource Economics at the University of Copenhagen and the Vietnamese office of Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) has found a shift in values driving illegal procurement of horn from endangered rhinos. Powdered horn is believed to have healing properties and can fetch up to 500,000 kroner per kilo (€67,000). The World Wildlife Fund (WWF) estimates that 1,054 rhino were killed by poachers in South Africa in 2016 and the worldwide number of rhinos remaining is estimated to be 30,000.Until now, the prevailing wisdom has been that consumers seek out rhinoceros horn for medical and health-related reasons, such as cancer treatments, hangovers and other ailments. The new study reveals more."For us, the surprising trend is that horn is increasingly being used as a symbolic gesture to console terminally ill family members. The horns are intended to provide the ill with a final source of pleasure and to demonstrate that their families have done everything possible to help them," explains Associate Professor Martin R. Nielsen of the Department of Food and Resource Economics. Along with colleague Dang Vu Hoai Nam of GIZ, Nielsen conducted in-depth interviews with 30 recent purchasers of rhino horn in Hanoi and Ho Chi Min City, Vietnam.The information gained by the study can be used by public authorities and organisations working to reduce the illegal trade in rhinoceros horn by improving their understanding of consumers and will be an important aspect of future campaigns aimed at reducing demand."Understanding the motivation of horn buyers is vital for addressing this problem. Among other things, our results demonstrate that the nature of demand changes over time. As a result, we must continually rethink strategies to curb the trade in rhinoceros horn," says Martin R. Nielsen.Besides using horn to console terminally ill family members, the 30 Vietnamese interviewed also used horn for treating hangovers and as a status symbol in business relations. The study also found that buyers are mainly interested in horn sourced from wild rhinos and willing to pay a premium for wild rather than farmed animal horn. Consequently, the researchers believe that a legal, controlled trade of farmed rhino would most likely not serve to reduce poaching."The study suggests that information about the decline of rhinoceros populations and awareness about hunting being controlled by organised crime does not affect consumer demand. Dealing with the problem requires other strategies," explains Martin R. Nielsen.The rhino horn trade is among one of the most organised forms of environmental crime, and the number of rhinos killed by poachers has increased markedly since 2008. Because Vietnam is the country with the greatest demand for rhinoceros horn, it also bears the brunt of the blame for poaching.The majority of remaining wild rhinoceros live in South Africa, where the population of white rhinoceros is estimated to be between 19,000 and 21,000.
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Endangered Animals
| 2,018 |
May 14, 2018
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https://www.sciencedaily.com/releases/2018/05/180514091504.htm
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Location of protected areas vital to wildlife survival
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Location, location, location is not just a buzzword for homebuyers.
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A new study, by 17 conservation scientists and environmental scholars, say the exact location of protective wild spaces is just as vital as committing to set these areas aside."Where Canada protects land is a significant decision," says UBC Okanagan researcher Laura Coristine, the study's lead author. "We wouldn't build a school in the highest traffic density area in a city -- especially if few children live there. Selecting a site for a protected area similarly needs to guard against current threats to species and safeguard biodiversity into the future."The research provides a first-ever framework to identify geographical hotspots that have the ecological potential to protect wild places and species from biodiversity loss associated with the global extinction crisis. The study, "Informing Canada's Commitment to Biodiversity Conservation" uses five key ecological principles to guide the creation of the next generation of Canada's protected areas: preserve habitat for species at risk, represent Canada's diverse ecosystems, conserve remaining wilderness, ensure landscape connectivity, and protect areas that are more resilient to climate changes."Canada is a country rich and diverse in natural beauty, wildlife and resources," says Coristine. "As one of the largest countries in the world, Canada's commitment to protect 17 per cent of our land and inland water areas by 2020 is of global consequence. However, the Canadian government currently has no systematic, scientific way of accomplishing this goal to maximize conservation benefits."Coristine is a Liber Ero postdoctoral researcher at UBC's Okanagan campus. She works out of the Wildlife Restoration Ecology research lab with Assistant Professor Adam T. Ford, who teaches biology in the Irving K. Barber School of Arts and Sciences."The world's wildlife is in rapid decline," says Ford, a Canada Research Chair in Wildlife Restoration Ecology. "Decisions about where land is protected and the extent of protection are of paramount importance."Canada and 167 other countries are signatories to the international Convention on Biological Diversity, which pledges to reverse trends in species decline. Increasing the amount of protected lands is one way to do this."The framework provides a first step in the broader process of protected area decision-making and is intended to help identify the best ecological opportunities to protect Canada's rich natural heritage," explains Ford."Our research brings into focus the tough choices that need to be made -- do we protect species at risk or pristine environments? Do we focus on the present day or ensure connectivity in a changing world?" says study co-author, Sally Otto, at UBC's Vancouver campus. "Or, as presented in our paper, do we strive to balance each of these needs?"The paper states that Canada, a diverse land with 194 unique ecoregions, is home to much of the world's remaining intact wilderness. But most of this country's at-risk species live in the highly-populated south. Hundreds of bird, mammal and fish species have declined in population -- in many cases due to habitat loss -- and more than 735 species are at risk of extinction. Because climate change is causing additional problems, the report stresses the importance of connecting areas for migration while also protecting areas that are more resilient to climate change."Now is a critical time for the country to decide what is it that we most want to protect," says Coristine. "What we choose not to protect, we risk losing; what we protect remains a legacy for the future."The study provides maps where protected areas would best meet conservation goals and an online tool where people can identify protected area sites using their own criteria.Coristine is one of 13 of the 17 co-authors who are members of the Liber Ero Fellowship Program, which supports emerging environmental leaders and their research. The study is funded by the program and will be published Monday, May 15 in the Canadian journal
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Endangered Animals
| 2,018 |
May 10, 2018
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https://www.sciencedaily.com/releases/2018/05/180510150039.htm
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Global trade spreads deadly frog disease from Asia
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New research has revealed a deadly disease that threatens the survival of the world's frogs originated from East Asia, and global trade was almost certainly responsible for the disease's spread.
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The frog chytrid fungus (It has spread around the world but until now it has remained unclear where killer strains of the pathogen first emerged.An international team of researchers led by Imperial College London, including four scientists from the One Health Research Group at James Cook University, traced the ancestor of the pathogen to a single strain in East Asia.Their findings support the idea that rather than dating back thousands of years, as previously thought, the range of the disease expanded greatly between 50 and 120 years ago, coinciding with the rapid global expansion of intercontinental trade.According to the researchers, human movement of amphibians -- such as through the pet trade -- has directly contributed to spreading the pathogen around the world.JCU's Dr Lee Skerratt, one of the authors of the paper, said the findings highlight the importance of global biosecurity measures."Australia has strict rules and regulations surrounding biosecurity and this finding confirms why regulations are so important," Dr Skerratt said."We hope this news will push policy change in countries with less strict biosecurity measures."The team also uncovered additional strains of the fungus that could cause further species decline, highlighting the importance of strict biosecurity policies."If more strains are allowed to spread we could see additional extinctions," Dr Skerratt said."Countries need to act now to improve regulations before these additional strains spread."Chytrid fungus causes a disease called chytridiomycosis that leads to heart failure, and is responsible for the decline or extinction of hundreds of species of frogs.The paper, Recent Asian origin of chytrid fungi causing global amphibian declines, was published in These findings come on the 20th anniversary of Dr Lee Berger's discovery during her PhD that the chytrid fungus is the cause of global amphibian species decline.Dr Berger led the Australian contribution and was an Australian Research Council Future Fellow and Postdoctoral Fellow at James Cook University from 2004 to 2016.
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Endangered Animals
| 2,018 |
May 9, 2018
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https://www.sciencedaily.com/releases/2018/05/180509162709.htm
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For lemurs, size of forest fragments may be more important than degree of isolation
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Occurrence probability of three lemur species in tropical dry forest increases with fragment size but can increase or decrease with fragment isolation depending on the species, according to a study published May 9, 2018 in the open-access journal
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Lemurs live only in Madagascar, and nearly all species are at risk of extinction primarily due to habitat loss and fragmentation. The independent effects of forest loss and of forest fragmentation are not well understood, however. To assess the relative impact of these threats, Steffens and Lehman surveyed lemurs in fragmented dry deciduous forest in Ankarafantsika National Park, Madagascar between June and November 2011, observing six lemur species in 42 forest fragments. The researchers then used incidence function models to examine whether the lemurs formed metapopulations, spatially-separated populations within a species, in a fragmented landscape and under different forest fragmentation conditions.In their simulations, the researchers found that three of the lemur species did form metapopulations in forest fragments. Within these metapopulations, occurrence was affected by both forest fragment size and isolation. However, fragment size appeared to be more important in determining lemur occurrence, with larger forest patches being associated with increased lemur occurrence.Madagascan forests are becoming increasingly fragmented, and this work helps to clarify how lemurs respond. It appears to be helpful to use a metapopulation approach when studying lemurs, and maintenance of habitat area may be crucial to maintaining populations in this fragmented landscape."Some lemur species are capable of tolerating high levels of habitat loss and fragmentation by forming metapopulations," says Travis Steffens. "In metapopulations occurrence probability is positively related to habitat area for each species while isolation has species-specific positive, negative and neutral impacts on occurrence probability."
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Endangered Animals
| 2,018 |
May 9, 2018
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https://www.sciencedaily.com/releases/2018/05/180509135407.htm
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Rapid evolution fails to save butterflies from extinction in face of human-induced change
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The evolution of wild species, adapting them to human management practices, can cause localised extinctions when those practices rapidly change. And in a new study published in
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A large, isolated population of a North American butterfly evolved complete dependence on an introduced European weed to the point where the continued existence of the butterfly depended on the plant's availability. The insects then became locally extinct when humans effectively eliminated that availability, confirming a prediction made by the same authors in a 1993 Thus the advent of cattle ranching more than 100 years ago set an eco-evolutionary trap that the insects obligingly fell into, and the trap was sprung when humans suddenly removed the cattle, withdrawing their 'gift', and driving the butterflies to extinction.European conservation biologists have long believed this to be the process underlying many local extinctions across Europe, and this study provides the first hard evidence of the process in action in real time. It also foreshadows an increasing importance of maintaining historical land use practices, including cattle ranching, as conservation measures in North America.The authors, affiliated to the University of Plymouth, the University of Texas at Austin and CNRS Moulis, have spent more than three decades studying changes in the diet of Edith's checkerspot (Euphydryas editha) in a spring-fed meadow surrounded by semi-desert sagebrush and pine forest on a family-run ranch in Nevada.In particular, the authors assessed the impact of narrow-leaved plantain (Plantago lanceolata), which was introduced to the USA in hay brought from Europe and flourished under cattle-grazing, probably arriving in Nevada more than 100 years ago.As soon as the butterflies encountered the plantain, their caterpillars survived better on it than on their traditional host, Blue-Eyed Mary (Collinsia parviflora), causing the adults to evolve preference for laying eggs on the plantain. By the mid-2000s, they were 100% reliant on the plantain and the Collinsia had been abandoned.However, within three years of the ranch's cattle being removed due to financial pressures, the butterflies became locally extinct as the grasses around their favoured new host were no longer grazed, and the plantains became embedded in those grasses, cooling the micro-environment. The Collinsia was unaffected by removal of cattle, so if the butterflies had not evolved so rapidly in response to the introduction of the plantain, they would most likely have survived.Around five years after the extinction, Edith's checkerspots recolonized the meadow. Since they were all found feeding on Collinsia, the original host plant, scientists believe these colonists to be a new population, and that the lineage which had called the ranch home for several decades no longer exists.They say the results are similar to that seen in British species such as the large blue butterfly, which went extinct across southern England following a reduction of grazing by both rabbits and sheep. Once this process was understood, the butterflies could be successfully re-introduced.Professor Singer, who has been studying the diet of Edith's checkerspot for more than 50 years and led the current study, said: "This is a clear example of how humans are able to change habitats faster than even rapidly-evolving species can change their behaviour. This cannot be not an isolated phenomenon, so unless we become aware of the potential consequences of such actions we will continue to inadvertently cause population extinctions of native species, without recognizing what we are doing. Species-level extinctions are possible when human activities are synchronized across wide areas."Professor Parmesan, a lead contributor to the Intergovernmental Panel on Climate Change which was awarded the Nobel Peace Prize in 2007, said the study had potentially wider implications beyond the scope of changes to farming practices.She added: "Climate warming is another form of anthropogenic change that is occurring faster than past natural changes, and is likely to cause problems for species whose evolution is unable to keep pace. If climate change were natural, it is likely that many wild species would be able to adapt, both through current evolution and through flexible changes in behaviour and life history. But human-driven climate change is occurring at a much faster rate than most past major climatic shifts. Ecologists have long been arguing that this is likely to lead to more extinctions than have happened with past climatic changes and this study supports the arguments that rapid climate change will prove detrimental to biodiversity both in the short and long term."
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Endangered Animals
| 2,018 |
May 9, 2018
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https://www.sciencedaily.com/releases/2018/05/180509104956.htm
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Breeding benefits when love bites wombats on the butt
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Monitoring wombats for behaviours such as pacing and rump biting could help conservation efforts by increasing the success of captive breeding.
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University of Queensland researchers have found increased pacing by female southern hairy-nosed wombats is an indicator they are 'in season'.And female wombats are more likely to bite the rumps of the males in pre-copulatory behaviour at the most fertile phase of their reproductive cycle.Associate Professor Stephen Johnston said researchers were trying to better understand the southern hairy-nosed wombat as a breeding model for their critically endangered northern cousins."With only about 200 northern hairy-nosed wombats remaining, being able to breed these animals may one day ensure the survival of the species," he said."There has been no captive breeding of the northern hairy-nosed wombat, and even the southern species fails to breed regularly in captivity."Dr Johnston said the size and aggressive temperament of wombats made them difficult to work with, so behavioural indicators were a significant step forward."We have developed a way to map the reproductive cycle of the female wombat by measuring hormone levels in their urine," Dr Johnston said."Through round-the-clock monitoring over multiple breeding cycles, we detected subtle behavioural changes associated with the fluctuations in this hormonal mapping."These behaviours could be used to identify when animals in captivity should be brought together for breeding, serving as cues for animal husbandry managers in zoos and wildlife facilities with southern hairy-nosed wombats."The research team, including Dr Alyce Swinbourne, worked with Australian Animals Care and Education, from their Safe Haven base at Mr Larcom in Central Queensland.Dr Johnston said that detection of the most appropriate timing for successful mating in the wombat was important not only for natural conception in wombats, but also for the next step in the research program, which involves the development of assisted reproductive techniques such as artificial insemination.
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Endangered Animals
| 2,018 |
May 8, 2018
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https://www.sciencedaily.com/releases/2018/05/180508090748.htm
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Scientists dive into museum collections to reveal the invasion route of a small crustacean
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Biological invasions are widely recognised as one of the most significant components of global change. Far-reaching and fast-spreading, they often have harmful effects on biodiversity.
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Therefore, acquiring knowledge of potentially invasive non-native species is crucial in current research. In particular, it is important that we enhance our understanding of the impact of such invasions.To do so, Prof Sabrina Lo Brutto and Dr Davide Iaciofano, both working at the Taxonomy Laboratory of the University of Palermo, Italy, performed research on an invasive alien crustacean (The studied species belongs to a group of small-sized crustaceans known as amphipods. These creatures range from 1 to 340 mm in length and feed on available organic matter, such as dead animals and plants. Being widely distributed across aquatic environments, amphipods have already been proven as excellent indicators of ecosystem health.While notable for their adaptability and ecological plasticity, which secure their abundance in various habitats, these features also make amphipods especially dangerous when it comes to playing the role of invaders.Having analysed specimens stored at the Museum of Natural History of Verona and the Natural History Museum in Paris, the scientists concluded that the species has colonised European waters 24 years prior to the currently available records.The problem was that, back in 1985, when the amphipod was first collected from European coasts, it was misidentified as a species new to science instead of an invader native to the North American Atlantic coast.A closer look into misidentified specimens stored in museum collections revealed that the species has been successfully spreading along the European coastlines.Moreover, it was predicted that the amphipod could soon reach the Mediterranean due to the high connectivity between the sea and the eastern Atlantic Ocean through the Straits of Gibraltar -- a route already used by invasive marine fauna in the past.In the event that the invader reaches the Mediterranean, it is highly likely for the crustacean to meet and compete with a closely related "sister species" endemic to the region. To make matters worse, the two amphipods are difficult to distinguish due to their appearance and behaviour both being extremely similar.However, in their paper, the scientists have also provided additional information on how to distinguish the two amphipods -- knowledge which could be essential for the management of the invader and its further spread.The authors believe that their study demonstrates the importance of taxonomy -- the study of organism classification -- and the role of natural history collections and museums."Studying and monitoring biodiversity can acquire great importance in European aquatic ecosystems and coastal Mediterranean areas, where biodiversity is changing due to climate change and invasions of alien species," Prof Lo Brutto says. "In this context, specific animal groups play a crucial role in detecting such changes and they, therefore, deserve more attention as fundamental tools in biodiversity monitoring.""Regrettably, the steadily diminishing pool of experts capable of accurately identifying species poses a serious threat in this field."
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Endangered Animals
| 2,018 |
May 7, 2018
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https://www.sciencedaily.com/releases/2018/05/180507134645.htm
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Alligators on the beach? Killer whales in rivers? Get used to it
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Alligators on the beach. Killer whales in rivers. Mountain lions miles from the nearest mountain.
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In recent years, sightings of large predators in places where conventional wisdom says they "shouldn't be" have increased, in large part because local populations, once hunted to near-extinction, are rebounding -- thanks to conservation.Many observers have hypothesized that as these populations recover the predators are expanding their ranges and colonizing new habitats in search of food.A Duke University-led paper published today in the journal It finds that, rather than venturing into new and alien habitats for the first time, alligators, sea otters and many other large predators -- marine and terrestrial species alike -- are re-colonizing ecosystems that used to be prime hunting grounds for them before humans decimated their populations and well before scientists started studying them."We can no longer chock up a large alligator on a beach or coral reef as an aberrant sighting," said Brian Silliman, Rachel Carson Associate Professor of Marine Conservation Biology at Duke's Nicholas School of the Environment. "It's not an outlier or short-term blip. It's the old norm, the way it used to be before we pushed these species onto their last legs in hard-to-reach refuges. Now, they are returning."By synthesizing data from recent scientific studies and government reports, Silliman and his colleagues found that alligators, sea otters, river otters, gray whales, gray wolfs, mountain lions, orangutans and bald eagles, among other large predators, may now be as abundant or more abundant in "novel" habitats than in traditional ones.Their successful return to ecosystems and climatic zones long considered off-limits or too stressful for them upends one of the most widely held paradigms of large animal ecology, Silliman said."The assumption, widely reinforced in both the scientific and popular media, is that these animals live where they live because they are habitat specialists. Alligators love swamps; sea otters do best in saltwater kelp forests; orangutans need undisturbed forests; marine mammals prefer polar waters. But this is based on studies and observations made while these populations were in sharp decline. Now that they are rebounding, they're surprising us by demonstrating how adaptable and cosmopolitan they really are," Silliman said.For instance, marine species such as sting rays, sharks, shrimps, horseshoe crabs and manatees now make up 90 percent of alligators' diet when they're in seagrass or mangrove ecosystems, showing that gators adapt very well to life in a saltwater habitat.The unanticipated adaptability of these returning species presents exciting new conservation opportunities, Silliman stressed."It tells us these species can thrive in a much greater variety of habitats. Sea otters, for instance, can adapt and thrive if we introduce them into estuaries that don't have kelp forests. So even if kelp forests disappear because of climate change, the otters won't," he said. "Maybe they can even live in rivers. We will find out soon enough."As top predators return, the habitats they re-occupy also see benefits, he said. For instance, introducing sea otters to estuarine seagrass beds helps protect the beds from being smothered by epiphytic algae that feed on excess nutrient runoff from inland farms and cities. The otters do this by eating Dungeness crabs, which otherwise eat too many algae-grazing sea slugs that form the bed's front line of defense."It would cost tens of millions of dollars to protect these beds by re-constructing upstream watersheds with proper nutrient buffers," Silliman said, "but sea otters are achieving a similar result on their own, at little or no cost to taxpayers."
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Endangered Animals
| 2,018 |
May 7, 2018
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https://www.sciencedaily.com/releases/2018/05/180507111834.htm
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Carnivores in captivity give birth at the same time of year as those in the wild
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Many species have a specific mating season when living in their natural habitat. The young animals are usually born in spring when environmental conditions are optimal for their survival, while births at less favorable times such as the start of winter are thus avoided. Depending on whether seasonal reproduction is a strong characteristic of a species or not, the time period for births will be a longer or a shorter window.
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Researchers at the Clinic for Zoo Animals, Exotic Pets and Wildlife at the University of Zurich investigated the seasonality of more than 100 species of carnivores. As it is rather difficult to ob-serve births of animals in their natural habitat, they evaluated data from 150,000 births that took place in zoos. Zoos consistently document births and forward the information to the not-for-profit organization Species360 (Until now it was not known whether the seasonality of reproduction in the wild was also maintained when animals lived in zoos, where the animals have a sufficient supply of food all year round and can spend the winter in heated indoor spaces. "It is surprising how closely the zoo data correlates with that from animals in their natural habitat," says Marcus Clauss, UZH Professor at the Vetsuisse Faculty. For more than 80% of the species, the time period for births was the same in the zoo as in the wild. "Seasonality is an evolutionary feature and thus a fixed characteristic of a species -- most probably through a genetically determined reaction to a signal given by the length of daylight," adds Clauss. Only a few species -- those whose natural habitat is in the tropics and whose seasonal reproduction is for reasons of food availability -- start reproducing all year round when living in captivity, where food is always plentiful.The carnivores with the most pronounced seasonality characteristics include the red wolf (The researchers found two further interesting patterns: Many seasonal carnivores have gestation periods that are short relative to their body size, so that the embryo grows quickly enough between the mating period in fall and the birth date in spring. Others, however, have extended gestation periods so that they give birth at the right time of year. This extension does not occur through a slowing down of the embryo growth for example, but rather through a limited period of dormancy during which the fertilized ovum does not yet get implanted in the womb. "It seems that it is easier for evolutionary processes to speed up the embryo growth than to slow it down," concludes Clauss.The only exception to this rule is the sea otter ("It's fascinating to see how little reproductive seasonality is influenced by the conditions in a zoo, where enough food is available all year round, and therefore how the data from zoo animals can be used to describe species' biology," summarizes Clauss. In domestic pets, on the other hand, this connection to the wild barely exists anymore and their reproduction is not associated with a specific season. So if you want to see newborn animals, head to the zoo in April or May.
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Endangered Animals
| 2,018 |
May 7, 2018
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https://www.sciencedaily.com/releases/2018/05/180507084823.htm
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How land use and climate change are driving species distribution shifts
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Climate change is altering where species live all over the planet. With global warming, species are moving towards the poles and up elevation where temperature is lower. However, along with global climate change, the world is also experiencing massive changes in land-use which may also impact where species live. Could both of these forces be influencing current changes in species distributions?
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Fengyi Guo, an MPhil student in the School of Biological Sciences at the University of Hong Kong (HKU), decided to explore this question with her adviser Dr Timothy Bonebrake (HKU) and Dr Jonathan Lenoir, a Junior Research Scientist at the National Center for Scientific Research (CNRS) in France. Their findings, recently published in The results of this research have several implications for understanding global change impacts on biodiversity. An emphasis on climate change for understanding how species change their distributions has been important in recent years but must be understood in the context of land-use change as well. Additionally, the results show that tropical species may be especially vulnerable to the dual effects of climate and land-use changes. Finally, how species respond to both habitat loss and changing climates should be considered carefully for effective conservation and management of biodiversity.Increasing documentation of evidence for species redistribution under climate change in recent years made this research possible. "While the importance of land-use change for climate-driven species shifts has long been recognized, how land-use change is important or to what extent it affects species redistribution was never fully appreciated" noted Miss Guo. "Most of the studies we reviewed in this work stated that land-use remained unchanged over time while the data suggested otherwise and our results showed that these changes may have important implications."Dr Bonebrake added further that "this work also sheds light on possible climate change impacts on the species of Hong Kong -- while warming may be causing species to shift their distributions here, both forest recovery in country parks and forest loss from development in recent decades may hinder our ability to detect changes as species distributions shifts will be a consequence of multiple interacting human impacts."Overall the research emphasizes how species must contend with multiple human impacts on the natural world. While some species may be able to move (and do move) in response to climate change and/or land-use change, others may not. Those species that are unable to respond effectively to warming or habitat loss face a high risk of extinction.
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Endangered Animals
| 2,018 |
May 3, 2018
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https://www.sciencedaily.com/releases/2018/05/180503142802.htm
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World's rarest ape on the edge of extinction
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In a new research article, a team of international researchers argue that the Tapanuli Orangutan -- a species discovered last year in Sumatra, Indonesia, and one of the rarest animals on the planet -- could lose its battle for survival, unless decisive steps are taken to rescue it.
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"In forty years of research, I don't think I've ever seen anything this dramatic," said Professor William Laurance from James Cook University in Australia, leader of the research team."This is just the seventh species of Great Ape ever discovered, and it could go extinct right before our eyes," said Professor Jatna Supriatna from the University of Indonesia, a co-author of the study."Fewer than 800 of the apes survive, and they're under assault from mega-projects, deforestation, road building, and poaching," said Dr Sean Sloan, lead author of the article in "Their entire remaining habitat is unbelievably small -- less than a tenth the size of Sydney, Australia," said Sloan.The authors say the most imminent threat is a planned U.S.$1.6 billion mega-dam -- the Batang Toru project -- that would be constructed by a Chinese state-owned corporation, Sinohydro, and funded by Chinese financiers."If it proceeds, the dam will flood crucial parts of the ape's habitat, while chopping up its remaining habitat with new roads and powerlines," said Supriatna.The team discovered the ape survives only in areas with virtually no roads, which promote illegal logging, clearing, and poaching."This is a critical test for China and Indonesia. They say they want sustainable development -- but words are cheap," said Laurance."Without urgent action, this could be ecological Armageddon for one of our closest living relatives."
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Endangered Animals
| 2,018 |
May 3, 2018
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https://www.sciencedaily.com/releases/2018/05/180503085553.htm
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What the gorilla microbiome tells us about evolution and human health
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A study of the microbiomes of wild gorillas and chimpanzees offers insights into the evolution of the human microbiome and might even have implications for human health. The research project was led by scientists at the Center for Infection and Immunity (CII) at Columbia University's Mailman School of Public Health. Findings appear in the journal
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The researchers used genetic sequencing to analyze fecal samples collected by the Wildlife Conservation Society (WCS) from wild African great apes living the Sangha region of the Republic of Congo over the course of three years. Their goal was to understand the mix of gut microbes living in gorillas and chimpanzees and compare them to those already documented in other non-human primates and human populations. They found that gorilla and chimpanzee microbiomes fluctuate with seasonal rainfall patterns and diet, switching markedly during the summer dry period when succulent fruits abound in their environment and make up a larger proportion of their diet, as opposed to their usual, more fiber-rich diet of leaves and bark.These seasonal shifts in the microbiomes of gorillas and chimpanzees are similar to seasonal microbiome changes observed in the human Hadza hunter-gatherers from Tanzania, who also rely heavily on the seasonal availability of foods in their environment. Seasonal shifts in the microbiomes of human industrialized cultures, such as the United States, are likely less prevalent owing to reduced reliance on seasonally available foods and globalization of the food supply, as evident in any grocery store."While our human genomes share a great deal of similarity with those of our closest living relatives, our second genome (the microbiome) has some important distinctions, including reduced diversity and the absence of bacteria and archaea that appear to be important for fiber fermentation," says first author Allison L. Hicks, MS, a researcher at CII. "Understanding how these lost microbes influence health and disease will be an important area for future studies.""We observed dramatic changes in the gorilla and chimpanzee microbiomes depending on seasons and what they are eating," says senior author Brent L. Williams, PhD, assistant professor of Epidemiology at CII. "Bacteria that help gorillas break down fibrous plants are replaced once a year by another group of bacteria that feed on the mucous layer in their gut during the months they are eating fruits."The fact that our microbiomes are so different from our nearest living evolutionary relatives says something about how much we've changed our diets, consuming more protein and animal fat at the expense of fiber," says Williams. "Many humans may be living in a constant state of fiber deficiency. Such a state may be promoting the growth of bacteria that degrade our protective mucous layer, which may have implications for intestinal inflammation, even colon cancer."All great apes are endangered or critically endangered. Down to fewer than 500,000, their numbers have been reduced through deforestation-which destroys their habitat-and through hunting, including for meat. Even infectious disease is a major factor-as many as one-quarter of the world's gorilla population has died because of Ebola."We are losing biodiversity on a global scale," cautions co-author Sarah Olson, PhD, associate director of wildlife health at WCS. "In fact, our own human microbiome is not immune to this phenomenon. There is an ever growing need for conservation efforts to preserve environments that are vital to the health of animal populations.""This study underscores the importance of a One Health framework in focusing not only on diseases but also on understanding more about normal physiology," said co-author W. Ian Lipkin, MD, John Snow Professor of Epidemiology and director of CII. "It also provides evidence to support the adage that you are what you eat."
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Endangered Animals
| 2,018 |
May 2, 2018
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https://www.sciencedaily.com/releases/2018/05/180502153403.htm
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River dolphins are declining steeply in the Amazon basin
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Populations of freshwater dolphins in the Amazon basin are in steep decline, dropping by half about every decade at current rates, according to a study published May 2, 2018 in the open-access journal
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The Amazon basin is home to two species of river dolphins -- the boto (The analysis revealed that populations of both boto and tucuxi Amazonian dolphins are dropping rapidly. At current rates, boto populations are halving every 10 years, and tucuxi populations are halving every nine years. These rates of decline are some of the most severe of those known for cetaceans since the early years of modern whaling. The researchers conclude that if IUCN Red List criteria were applied based on this work, both species would be classified as Critically Endangered. River dolphins are legally protected in the Amazon basin, and given these findings, the researchers call for greater enforcement of these laws.
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Endangered Animals
| 2,018 |
May 2, 2018
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https://www.sciencedaily.com/releases/2018/05/180502131819.htm
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Are emperor penguins eating enough?
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For Emperor penguins waddling around a warming Antarctic, diminishing sea ice means less fish to eat. How the diets of these tuxedoed birds will hold up in the face of climate change is a big question scientists are grappling with.
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Researchers at the Woods Hole Oceanographic Institution (WHOI) have developed a way to help determine the foraging success of Emperor penguins by using time-lapse video observations relayed to scientists thousands of miles away. The new remote sensing method is described in the May 2, 2018, issue of the "Global warming may be cutting in on food availability for Emperor penguins," said Dan Zitterbart, a scientist at WHOI and co-author of the study. "And if their diets change significantly, it could have implications on the health and longevity of these animals -- which are already expected to be highly threatened or close to extinct by the end of this century. With this new approach, we now have a logistically viable way to determine the foraging success of these animals by taking images of their behavior once they return back to the colony from their foraging trips."Off all the penguin species, Emperor penguins tend to be the biggest eaters. And for good reason: they make exceptionally long treks on sea ice to reach their foraging grounds -- sometimes up to 75 miles during the winter -- and feed their large chicks when they return. But as sea ice diminishes, so does the microscopic plankton living underneath, which serves as the primary food source for fish that penguins eat. Sea ice also provides an important resting platform for the penguins in between foraging dives, so melting can make foraging that much harder.Determining the species' foraging success involves a two-step process. First, digital photos of the birds are taken every minute throughout the day using an inexpensive time-lapse camera perched above the colony 100 feet away. The camera is rugged enough to withstand up to ?50° Celsius temperatures and wind speeds above 150 kilometers per hour.Céline Le Bohec, a research scientist in ecology from the Centre national de la recherche scientifique (CNRS) and the Centre Scientifique de Monaco, and co-author of the study, says this spying capability overcomes a major limitation in Antarctic field research: the ability to monitor conditions remotely."It's really important to be able to understand how changing environmental conditions will impact penguin populations, but the harsh weather conditions and logistic difficulties linked to the remoteness of the white continent have made it very challenging to get information from over there," she said. "Now, with our observatories, especially remotely-controlled ones, we can go online anytime and instantly see what is happening in the colony.Moreover, due to their position at the upper level of the food web, working on top-predators such as Emperor penguins, is very useful for understanding and predicting the impact of global changes on the polar marine biome: it's like having an alarm system on the health of these ecosystems."Images are recorded and stored in an image database and later correlated with sensor-based measurements of air temperature, relative humidity, solar radiation, and wind. The combined data sets enable Zitterbart and his team to calculate a "perceived penguin temperature" -- the temperature that penguins are feeling. It is much like the wind chill factor for humans: the air temperature may be -12° Celsius, but other factors can make it feel colder."Early in the project, we thought if, for example, the wind was blowing faster than 15 meters per second, the penguins would always be huddling, regardless of the other environmental conditions," said Sebastian Richter, a Ph.D. student in Zitterbart's group and lead author of the study. "However, we did not find this to be true, and soon realized that we needed to account for the other weather conditions when assessing huddling behavior."By correlating the penguin's "wind chill" temperature with video observations of when the penguins begin huddling, they're able to come up with a "transition temperature" -- the temperature at which colonies shift from a scattered, liquid-like state to a huddled, solid-like state. If the transition occurs at warmer temperatures, it means the penguins are feeling cold earlier and begin huddling to stay warm and conserve energy. And that indicates that the penguins had less body fat upon their return from foraging and were probably undernourished because they did not find enough food to eat within a reasonable distance from their breeding colony. If the transition temperature is lower later in the season, it suggests that the foraging season was a success and the animals returned well-fed and with higher amounts of body fat.Zitterbart says the information may ultimately be used to derive conservation measures to protect Emperor penguins. According to a previous WHOI study, the species is critically endangered, and it's projected that by 2100, the global population will have declined by 20% and some colonies might reduce by as much as 70% of the current number of breeding pairs of Emperor penguins if heat-trapping gas emissions continue to rise and Antarctic sea ice continues to retreat."With the information produced by our observatories, population modelling will help us to better project the fate of the different colonies that are left," he said. "It's important to know which colonies are going to be the first most affected by climate change, so if it appears that a certain colony will remain strong over the next century, conservation measures like marine protected areas can be established to better protect them."
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Endangered Animals
| 2,018 |
May 1, 2018
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https://www.sciencedaily.com/releases/2018/05/180501193521.htm
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Researchers study how to improve southern sea otter survival
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University of Wyoming researchers have been studying how best to bolster the southern sea otter population, which suffers from low genetic diversity and has been further ravaged by Toxoplasma brain disease and others, shark attacks and illegal shootings by fishermen.
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Currently hovering at around 3,000 animals along the California coast, this small subspecies is listed as a threatened species under the federal Endangered Species Act."This paper provides analyses and data vitally necessary to southern sea otter recovery," says Holly Ernest, a UW professor of wildlife genomics and disease ecology, and the Wyoming Excellence Chair in Disease Ecology in the Department of Veterinary Sciences and the Program in Ecology. "The paper provides evidence that its genetic diversity is low and staying low. Even with modest increases in population numbers, genetic diversity has not increased.""Sea otters have recovered in their core area but have not recolonized where they used to be," says Erick Gagne, a former UW postdoctoral researcher who worked with Ernest on the study. "They are currently locked between just off the south of San Francisco Bay to just north of Santa Barbara. They used to go through to Oregon and connect with the northern sea otter."Currently, the northern sea otters, which are much more abundant, have a territory that ranges from northern Washington up through Alaska.Gagne, who is now a postdoctoral researcher at Colorado State University, was lead author and Ernest was senior author of a paper, titled "Measures of Effective Population Size in Sea Otters to Reveal Specific Considerations for Wide-Ranging Species," that was published May 1 (today) in Kyle Gustafson, a UW postdoctoral researcher, also was involved in the study. Researchers from the U.S. Geological Survey, University of California-Santa Cruz, the California Department of Fish and Wildlife, Seattle Aquarium and the Smithsonian Conservation Biology Institute in Washington, D.C., were other contributors to the paper.In the 1700s and 1800s, there were "a ton of sea otters" located up and down the California coast, and on up to Russia and Japan, Gagne says. Around 1900, southern sea otters, which had been hunted heavily, were thought to be extinct. Approximately 50 southern sea otters were discovered in the Big Sur area in 1938. About 3,000 remain today, Gagne says."When you have that large of a reduction, you lose genetic diversity," he says. "As the numbers recover, genetic diversity does not recover as rapidly, leaving the population vulnerable."Southern sea otters are important to the ecosystem because their diet includes a lot of invertebrates, including sea urchins and abalone, which graze on kelp. If sea otters did not eat these invertebrates, kelp forests, which provide food habitat for multiple species of fish, would be lost, Gagne says.However, as sea otter populations reach high numbers in the core, the southern sea otters' food supply becomes limited. In turn, this makes it difficult for the animal numbers to increase in their limited core range."Some biologists would like to see their (southern sea otter) range expand northward," Gagne says.While some northern sea otters could be relocated to breed with the southern sea otter population and increase southern sea otter numbers while simultaneously bolster genetic diversity, there is a potential downside. Northern sea otters could bring diseases with them or could try to swim back north and run into the "shark gauntlet" near San Francisco Bay, Ernest says. Sharks tend to congregate around the region, making it difficult for sea otters to disperse north of the bay.The southern sea otter is smaller than its similar counterpart, the northern sea otter. The facial structure and skull shape are different between the two, Gagne says.The paper examined one of the methods, known as "effective population size," that is included in the southern sea otter recovery plan. Effective population size is a measure of the individuals that are contributing genetically to the next generation of the species, Ernest explains.Conservation genetic techniques and considerations of the evolutionary potential of a species are increasingly being applied to species conservation. For example, effective population size estimates are useful for determining the conservation status of species. Yet, accurate estimates of current effective population size remain difficult to obtain, according to the paper.The paper shows that the way this method is calculated can make important differences in the final effective population size number. The U.S. Fish and Wildlife Service recovery plan uses effective population size to determine when the southern sea otter is to be delisted as a federally threatened species. If Fish and Wildlife use old methods of calculation, the southern sea otter may be delisted too soon for true recovery, Gagne says.After being hunted to near extinction during the North Pacific fur trade, the southern sea otter has recovered over part of its former range but remains at relatively low numbers, making it desirable to obtain accurate and consistent estimates of effective population size. Although previous theoretical papers have compared the validity of several methods, comparisons of estimators using empirical data in applied conservation settings are limited."Studies like these take decades," says Ernest, who has been studying southern sea otters for 13 years, dating back to her time as a researcher at the University of California-Davis.For this study, Gagne and Ernest combined 13 years of demographic and genetic data from 1,006 sea otters to assess multiple effective population size estimators, as well as temporal trends in genetic diversity and population genetic structure. Genetic diversity of the southern sea otter was low and did not increase over time, according to the paper. There was no evidence for distinct genetic units, but some evidence for genetic isolation by distance, the paper concludes."To get this 13-year data set was really valuable," Ernest says.Based on their results, Gagne, Ernest and the paper's co-authors recommend the development of new delisting criteria for the southern sea otter. They advise the use of multiple estimates of effective population size for other wide-ranging species, species with overlapping generations or with sex-biased dispersal, as well as the development of improved metrics of genetic assessments of populations."We need new measures to assess their genetic well-being," Gagne says. "That's the next step for sea otters and other endangered species."
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Endangered Animals
| 2,018 |
May 1, 2018
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https://www.sciencedaily.com/releases/2018/05/180501161800.htm
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Sea turtle nesting beaches threatened by microplastic pollution
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Plastic is famous for its unyielding durability, making it perfect for consumer products but a unique and persistent menace to the natural environment.
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For the loggerhead sea turtles that nest on the once-pristine beaches bounding the Gulf of Mexico, millimeters-thick pieces of broken down plastic -- called microplastics -- pose a particularly urgent threat.A new study from Florida State University researchers shows that increasing microplastic accumulation along the Gulf's beaches could alter the composition of shoreline sand and jeopardize the turtles' sensitive incubation environments.Their findings were published in the journal "With increasing populations, higher demand for resources and more use of plastic, we're having a lot more plastic and microplastic appearing as marine debris," said the study's coauthor Mariana Fuentes, assistant professor of Earth, Ocean and Atmospheric Science (EOAS). "In these coastal areas, we're seeing significantly more pollution."For the study, EOAS student researcher Valencia Beckwith surveyed the Northern Gulf of Mexico Loggerhead Recovery Unit's 10 most important loggerhead turtle nesting sites in Florida.Sand samples collected throughout the region revealed that microplastics were present at every site. More alarming, the highest concentrations of microplastics were found consistently in the dunes, where sea turtles tend to nest.Plastic has a tendency to retain large amounts of heat in response to comparably moderate increases in temperature. If enough plastic is present in a sandy environment, the area could experience measurable temperature increases.This dynamic is of particular concern in sea turtle nests, Fuentes said. For marine turtle eggs, incubation temperature is destiny."Sea turtles have temperature dependent sex determination, which means their sex is determined by the sand temperature," Fuentes said. "Changes in incubation temperatures might modify the sex ratios produced on these nesting beaches, but at this stage we don't know how much microplastic is needed to see those changes."In subsequent research, Beckwith and Fuentes plan to expand upon these findings and investigate the specific ways that microplastic might alter the temperature profile of the sediment on important nesting beaches."The first step was to see whether sea turtles are exposed to microplastics," she said. "Next we'll explore its potential impacts."Earth's oceans have long been blighted by pollution, and vulnerable species like sea turtles have borne the brunt of decades of irresponsible waste. But Fuentes remains optimistic about the future. She said that shifting attitudes could translate into positive changes in policy and behavior."There is a lot of hope," Fuentes said. "We're beginning to see more and more initiatives providing incentives to discourage the use of plastics. I see my students making those changes every day. It's up to everyone."
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Endangered Animals
| 2,018 |
April 30, 2018
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https://www.sciencedaily.com/releases/2018/04/180430102508.htm
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If pigs could fly: How can forests regenerate without birds?
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Human activity continues to shape environmental systems around the world creating novel ecosystems that are increasingly prevalent in what some scientists call the Anthropocene (the age of humans). The island of Guam is well known as a textbook case for the devastating effects of invasive species on island ecosystems with the extirpation of most of the forest dwelling birds due to brown tree snake predation. The loss of native birds has resulted in a loss of forest seed dispersers. Recent research conducted by lead author Ann Marie Gawel, based on her University of Guam master's thesis, has found an unlikely forest ally, feral pigs.
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With the loss of birds in the limestone forests on Guam, seed dispersal for native plants has become problematic. The damage caused by ungulates, introduced deer and pigs, has been documented in tropical forests worldwide. Less documented is the effect of these animals on seed dispersal of native and nonnative forest plant species.Gawel's study examined scat from deer and pigs foraging in the limestone karst forests of northern Guam. Her findings indicate that pigs, featherless and flightless, might be one of the last seed dispersers left on the island to assist in forest regeneration. Particular to limestone forests, where pigs would be hard pressed to find places to wallow and root, this study found negative impacts from the presence of deer but did not detect negative impacts from pigs.This finding is important for informing conservation and forest restoration practices. Although the removal of ungulates has proven beneficial in managing forest systems; for Guam, removing pigs from limestone forests may have a detrimental effect on the regeneration of the plant communities of those forests. "The browsing preferences of ungulates on the island of Guam have directly impacted the diversity and make up of forest species for many years. Our research indicates the need for ungulate control that addresses the ecological role that pigs have been providing to limestone forests since the loss of native seed dispersers," noted Gawel.The most successful conservation strategies vary from species to species. Gawel's Guam research suggests consideration of the possible role non-native species may play in novel ecosystems is necessary.
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Endangered Animals
| 2,018 |
April 27, 2018
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https://www.sciencedaily.com/releases/2018/04/180427100317.htm
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Capturing of the rare Yanbaru whiskered bat
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The critically endangered Yanbaru whiskered bat,
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The rare bat species was first discovered in the subtropical Yanbaru Forest in 1996, when two specimens were collected. It was later observed on a few occasions on the islands Tokunoshima and Amami-Oshima, but no sightings were reported again on Okinawa Island.This small tree-dwelling bat, endemic to these islands, thus became a serious conservation concern and was declared 'critically endangered,' the highest risk level, by both the Japanese Ministry of Environment and the International Union for the Conservation of Nature.On 20 February 2018 at 20:05, Preble captured one male Moreover, Preble was able to record the bat's echolocation call, vital data that was previously unreported.This large area of forest was returned to Japan in December 2016, and Kyoto University's Island Bat Research Group, led by Christian Vincenot, was among the first teams to be granted access by the Ministry of Environment, Okinawa Forestry Office, and Aha Dam authority.The presence of the Yanbaru whiskered bat indicates that this zone, which was off limits for over a half-century, may have served as an unintended wildlife sanctuary. This discovery revives hope for conservation of this rare species, while also suggesting that Myotis yanbarensis may be range-restricted to a small part of the Yanbaru Forest and therefore may continue to be at risk of local extinction.Extreme caution is therefore advised in the management of this area, which is currently a candidate for UNESCO Natural Heritage status. Bats are often highly sensitive to infrastructure development, as seen in the steep decline in endangered populations following the construction in 2013 of a new airport runway over bat caves on Ishigaki island, also in the Okinawan archipelago.
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Endangered Animals
| 2,018 |
April 25, 2018
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https://www.sciencedaily.com/releases/2018/04/180425162028.htm
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Massive study across western equatorial Africa finds more gorillas and chimpanzees than expected
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A massive decade-long study of Western Equatorial Africa's gorillas and chimpanzees has uncovered both good news and bad about our nearest relatives. The good news: there are one third more western lowland gorillas and one tenth more central chimpanzees than previously thought.
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The bad news: the vast majority of these great apes (80 percent) exist outside of protected areas, and gorilla populations are declining by 2.7 percent annually.The WCS-led study titled "Guns, germs and trees determine density and distribution of gorillas and chimpanzees in Western Equatorial Africa" appears in the latest edition of the journal The newly published paper was written by 54 co-authors from several organizations and government agencies, including WCS (Wildlife Conservation Society), WWF (World Wide Fund for Nature), Max Planck Institute for Evolutionary Anthropology, Jane Goodall Institute, Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) -- Monitoring the Illegal Killing of Elephants (MIKE), Lincoln Park Zoo, and the Universities of Stirling and Washington, and involved the protected area authorities of five countries. Researchers collected field data during foot surveys carried out over a 10-year period across the range of both western lowland gorillas (Gorilla gorilla gorilla) and central chimpanzees (The authors of the study report an estimated abundance of over 360,000 gorillas and nearly 130,000 chimpanzees across the combined ranges of both subspecies, both of which were higher than previously believed. The gorilla estimate is approximately one-third higher and the chimpanzee estimate is about one-tenth higher. These revised numbers come largely from refinements to the survey methodology, new data from areas not previously included in range-wide estimates, as well as predictions of numbers in the areas between survey sites."It's great news that the forests of Western Equatorial Africa still contain hundreds of thousands of gorillas and chimpanzees, but we're also concerned that so many of these primates are outside of protected areas and vulnerable to poachers, disease, and habitat degradation and loss," said lead author Samantha Strindberg of WCS. "These findings can help inform national and regional management strategies that safeguard the remaining habitat, increase anti-poaching efforts, and curtail the effects of development on great apes and other wildlife."Although the majority of great apes were found outside of protected areas, they were still in large forested landscapes close to or bordering existing national parks and reserves and away from centers of human activity. This suggests that protecting large and intact forested areas, with protected areas at their core, is critical to conserving gorillas and chimpanzees in this region.The data analysis also revealed a 2.7 percent annual decline in gorilla numbers, a finding that supports the continued status of the species as "Critically Endangered" on the IUCN Red List of Threatened Species. Chimpanzees are listed as "Endangered."The combined field time spent by researchers collecting data for the study totaled approximately 61,000 days (or 167 person-years) of time. Researchers walked more than 8,700 kilometers (5,400 miles) -- a distance longer than the north-south axis of the African continent, or from New York to London -- while collecting data on great ape nests that was used to generate population estimates and trends.Said co-author Dave Morgan of the Lincoln Park Zoo and Goualougo Triangle Ape Project: "The boots on the ground research teams and partnerships are crucial to the success of these programs and the conservation of gorillas and chimpanzees. These long-term studies enable us to make informed recommendations regarding protected lands and management to help great apes."The main factors responsible for the decline of gorillas and chimpanzees are illegal hunting, habitat degradation, and disease. At the same time, it was clear that where wildlife guards were present, above all in protected areas with intact forests, both gorillas and chimpanzees can thrive.David Greer of WWF said: "All great apes, whether in Africa or Asia, are threatened by poaching, especially for the bushmeat trade. Our study found that apes could live in safety, and thus in higher numbers, at guarded sites than if there was no protection."Said Fiona Maisels of WCS: "Our study underscores the huge importance of intact forests to gorillas and chimpanzees, and of preventing illegal felling of good quality forests."Other conservation recommendations made by the authors include land-use planning at national scales to keep ecologically-harmful activities, such as agriculture and new road construction, away from intact forests and the protected areas that serve as important gorilla and chimpanzee refuges.Another priority is the implementation of careful logging practices in existing logging concessions that follow Forest Stewardship Council (FSC) Standards for reducing impacts on wildlife and habitats. These standards require that access to forests is controlled, old logging roads are effectively decommissioned and effective patrol systems are put in place to prevent illegal hunting. Ensuring strong implementation is critical.An additional threat to great apes -- as well as human health -- is the Ebola virus disease. Continued research into developing a vaccine and the means to deliver it are priorities, as are educational efforts on how to avoid spreading the disease and transmission between humans and great apes.Of all the 14 living great ape taxa, western lowland gorillas and central chimpanzees have the largest remaining populations. This is certainly good news. However, their future preservation cannot be taken for granted, given the fact that their dependence on suitable habitat collides with local to global demand for natural resources from their habitat, particularly outside of protected areas, where most of them occur.Said Hjalmar Kühl of the Max Planck Institute for Evolutionary Anthropology: "Protecting our gorillas and chimpanzees will therefore require a major increase in political will at all levels -- national, regional, and global. Financial commitments from governments, international agencies for endangered species conservation and the private sector, are also critical for conserving our closest relatives and their habitats."Liz Williamson from the University of Stirling and the IUCN Red List Authority Coordinator for great apes said: "A combination of responsible industrial practices, conservation policies, and a network of well-managed parks and corridors would provide wildlife managers with a winning formula for conserving great apes in Central Africa. Our study has revealed that it is not too late to secure a future for gorillas and chimpanzees."
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Endangered Animals
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April 25, 2018
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https://www.sciencedaily.com/releases/2018/04/180425131813.htm
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Endangered petrels and trawl fishing clash in Tasman sea
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Today's shifting environmental conditions are creating an uncertain future for many top predators in marine ecosystems, but to protect the key habitat of a species, you first have to know where that habitat is and what threats might be affecting it. A new study from
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The Museum of New Zealand Te Papa Tongarewa's Susan Waugh and her colleagues outfitted 73 petrels with GPS loggers over the course of four breeding seasons to track where they went during their foraging trips in the Tasman Sea. The results show that the birds' core feeding areas were consistent from year to year, located within 250 kilometers of their breeding colonies and focused on highly productive areas where the seafloor is steeply sloped. These sites often overlap with areas of significant trawl fishing activity, and further data is needed to see whether this co-occurrence translates into bird mortality. The species is the tenth most at-risk species from the impacts of New Zealand commercial fishing, but it appears that its actual ranking may be even higher as a result of the finding that the species is exposed to more fisheries activity than was previously understood."Our work on Westland petrels started in 2010, with a desire to understand how this species was faring demographically, as well as the key influences on it," says Waugh. "Our work highlights a key factor in the birds' ecology that has strong implications for conservation -- these birds predictably use the same waters year in and year out, regardless of El Niño cycles, and they are therefore a great candidate for a marine protected area to create protection of their trophic relationships. We feel this Westland Petrel foraging data will provide a high-quality information source to help define key areas for marine conservation that will also provide protection for a whole suite of species.""A remarkable and important aspect of this study is that they performed this investigation during a six-year period, encompassing a variety of environmental conditions. Whatever the sex or the breeding stage considered, Westland Petrels consistently foraged in the same core areas from year to year," adds Christophe Barbraud of the French National Centre for Scientific Research, a seabird conservation expert who was not involved in the study. "Since these areas were also consistently and heavily used by trawl fisheries, these results call for the implementation of marine spatial management tools, such as marine reserves or restrictions and monitoring of interactions between individual Westland Petrels and trawl fisheries, to ensure the conservation of this endangered petrel species."
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April 25, 2018
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https://www.sciencedaily.com/releases/2018/04/180425120250.htm
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Protect forest elephants to conserve ecosystems, not DNA
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Although it is erroneously treated as a subspecies, the dwindling African forest elephant is a genetically distinct species. New University of Illinois research has found that forest elephant populations across Central Africa are genetically quite similar to one another. Conserving this critically endangered species across its range is crucial to preserving local plant diversity in Central and West African Afrotropical forests -- meaning conservationists could save many species by protecting one.
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"Forest elephants are the heart of these ecosystems -- without them, the system falls apart, and many other species are jeopardized," said the principal investigator of this research, Alfred Roca, a professor of animal sciences at the Carl R. Woese Institute for Genomic Biology and College of Agricultural, Consumer and Environmental Sciences (ACES).African forest elephants (Published in This nuclear DNA lacks the geographic patterns preserved in forest elephants' mitochondrial DNA, the small proportion of the genome that is passed down only from mothers to their offspring. The mitochondrial DNA suggests that five genetically distinct populations existed in the past, most likely due to the Ice Age when their habitat was greatly restricted."Forest elephant's seemingly discordant DNA can be easily explained by their behavior," said lead author Yasuko Ishida, a research scientist in ACES. "Their mitochondrial DNA is a relic preserved by their matriarchal society."Females live together in matrilineal family groups, a herd is made up of related females who share the same mitochondrial DNA. Nuclear DNA diversity is controlled by the largest, mature males who travel long distances and promote gene flow by mating with distant females. Thus, females ensure mitochondrial DNA persists in local populations, while males ensure that the nuclear DNA is shared across populations."However, all of this precious DNA may soon be eradicated as forest elephants face extinction due to poaching and habitat loss," Roca said. "Between 2002 and 2011, poachers wiped out more than half of their population. Fewer than 100,000 forest elephants are estimated to remain today -- we must act swiftly to preserve them, and by extension, their habitats."
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April 25, 2018
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https://www.sciencedaily.com/releases/2018/04/180425093834.htm
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Human impact on sea urchin abundance
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Sea urchin populations are more sensitive to human activities than previously believed, according to a half-century observational study. Researchers found that changing water temperature and algal blooms strongly affected sea urchin populations and even caused some abnormal development of their larvae. The research is published in the journal
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Continuous long-term monitoring is important for detecting ecological changes and understanding their causes. Sea urchins are ecological drivers that can affect the dynamics of whole communities, thanks to their extensive eating of seaweed and large population fluctuations. They are also commonly found in shallow water and therefore subject to human influences, yet few long-term studies focus on their population health.Between 1963 and 2014, researchers studied the dynamics of three common species of sea urchins in a fixed area off Hatakejima Island, a marine reserve in southern Japan, making this the longest running study of its kind. Each year they conducted a survey of the area, and between 1983 and 2008, six surveys were taken of the entire coast. The three species showed similar overall trends, with large numbers in the 1960s and 1970s, abrupt declines in the late 1970s or early 1980s, and a recovery toward the late 1990s.The team from several Japanese institutes, found that red tide -- another term for algal bloom -- along with warm winter ocean temperatures, and current are related to the abundance and species richness of these three commonest sea urchins. Each species was affected by different factors, and in one, red tides were linked to abnormal development, providing a rare connection between larval and post-larval ecology of an intertidal animal -- one that is in water at high tide and out of water at low tide -- over a long term.Professor Tomoyuki Nakano, from Kyoto University said: "Our study is the longest of its kind into sea urchin populations, and demonstrates the importance of monitoring impacts of environmental stressors and addressing the mechanisms of changes in the abundance of not only sea urchins but other marine creatures."The team conclude that because human impacts will continue to affect marine invertebrates, long-term studies like this one will be invaluable in understanding ecological changes. Combining these observations with experimental approaches will shed light on relationships between environmental factors.
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Endangered Animals
| 2,018 |
April 24, 2018
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https://www.sciencedaily.com/releases/2018/04/180424141138.htm
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Killer whale genetics raise inbreeding questions
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A new genetic analysis of Southern Resident killer whales found that two male whales fathered more than half of the calves born since 1990 that scientists have samples from, a sign of inbreeding in the small killer whale population that frequents Washington's Salish Sea and Puget Sound.
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Only about 26 of the 76 endangered whales in the Southern Resident population are currently breeding, according to the analysis published this week in "The effective size of this population is really small," he said. "It's acting like a population of only 20-30 individuals."Authors of the research also include scientists from the North Gulf Oceanic Society and Center for Whale Research. While the new paper builds on earlier genetic studies, it also raises new questions about whether inbreeding may be contributing to the population's struggles. Southern Resident numbers have fallen to their lowest point in 30 years.The analysis identified four whales as highly inbred, including offspring of a father-daughter and mother-son pair, but noted that all four are still alive. Many additional whales may be inbred to a lesser degree. Other studies have estimated that more than half of Southern Resident calves die before or shortly after birth, and the new analysis suggests that inbreeding could be a contributing factor."We found a hint of a relationship showing that the less diverse you are, the less likely you are to live long," Ford said. "We don't yet know how much of a concern that is, but it's something we want to look at more carefully. It's possible that some of the problems this population has may be due to inbreeding."Many wild species maintain diversity through mixing that occurs when maturing animals strike out on their own, often joining or forming new family groups. Southern Residents do not follow that strategy, with whales staying with their mothers and their families throughout their lives. The reason is not clear; the whales may see more benefit to sticking with their families because their mothers continue to help them hunt salmon as food.The drawback is that it puts the population at greater risk of inbreeding.While killer whales are generally flourishing worldwide, the isolated population of Southern Residents that eat primarily salmon is not. NOAA Fisheries has designated the population one of its eight national " The next link/button will exit from NWFSC web site Species in the Spotlight," and developed an The next link/button will exit from NWFSC web site Action Plan of stepped-up measures to promote its recovery. The population faces three main risks: lack of salmon prey, vessel traffic and noise, and chemical contaminants. The Action Plan includes measures to address all three risks in both the short and longer term.Researchers obtained DNA from skin and fecal samples for the genetic analysis, which identified two male whales, known as J1 and L41, as the fathers of more than half of the other sampled whales born since 1990. J1 fathered 16 of the Southern Residents with nine different females, while L41 fathered 20 whales with 11 different females. The two whales' offspring included whales in all three of the Southern Resident pods, indicating that there is genetic interchange between pods but that males also mate with females in their own pod.The number of breeding whales in the population has ranged from 12 to 53 over the past 40 years, the analysis found, with the oldest samples coming from a pre-1970 population with just 24 breeding whales. The analysis also found that the breeding success of male killer whales increases with age, with a median age of fatherhood at 31.With the Southern Resident population dominated by females that lead the tight-knit family groups, "it's kind of interesting to get a glimpse of what's going on with the dads here," Ford said.
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Endangered Animals
| 2,018 |
April 24, 2018
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https://www.sciencedaily.com/releases/2018/04/180424133607.htm
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Land use and pollution shift female-to-male ratios in snapping turtles
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Most of us know that our biological sex is decided by the pairing of X and Y chromosomes during conception.
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However, for many wildlife species, sex of offspring is determined after fertilization and often influenced by environmental factors, such as temperature. The sex of reptiles, for example, is based on temperatures in the nest while eggs incubate.Current research shows that increasing global temperatures as a result of climate change are expected to produce more female turtles since their offspring are influenced by the nest's temperature. But now, a team of Virginia Tech biologists has found that the nesting environment of turtles in agricultural habitats, which can ultimately lower nesting temperatures, can actually produce more males.To make matters worse, the researchers found that the effect of agricultural activities on sex ratios was exacerbated by the presence of mercury pollution. While it's known that mercury can impact reproduction in reptiles, this study provides the first documentation that mercury can influence sex determination. The common and pervasive environmental pollutant, when transferred from mother to offspring, was found to increase the number of male offspring even more.The findings, which were recently published in the journal "Our work illustrates how routine human activities can have unexpected side effects for wildlife," said William Hopkins, professor of wildlife conservation in the College of Natural Resources and Environment and lead researcher of the Wildlife Ecotoxicology and Physiological Ecology Lab at Virginia Tech, who oversaw the study. "We found strong masculinizing shifts in sex ratios caused by the interaction of two of the most common global changes on the planet, pollution and crop agriculture."The team worked along the South River in Virginia, where large amounts of mercury persist in the river and floodplain due to leaks from a nearby manufacturing plant in the river from 1929 to 1959. Field experiments were replicated simultaneously in the laboratory using high-resolution temperature profiles to confirm results from the field.In the field, temperature probes placed in each nest recorded temperature at one-hour intervals throughout the incubation period, mid-May through September. Every eight days, samples were collected to determine soil moisture content, and vegetation growth was monitored for height, density, and ground cover surrounding the nests.Snapping turtles, they found, favor agricultural sites for nesting because they naturally select sun-exposed areas with loose soil, sand, and vegetation debris in which to dig their nests. Females are attracted to the open and sunny agricultural fields in the early summer; the sites quickly become shaded and cooled as dense, monoculture crops grow throughout the season. Cooler incubation temperatures in the nest mean more male offspring are produced."Our results indicate that turtles are attracted away from natural nesting habitat into agricultural habitats, and this decision has undesirable consequences for their reproductive success," said Hopkins. "Turtle populations are sensitive to male-biased sex ratios, which could lead to population declines. These findings are particularly alarming because freshwater turtles are one of the most endangered groups of vertebrates on earth."The team also analyzed mercury levels from maternal blood collected in the field as well as one random egg from each nest sampled. They found that higher concentrations of mercury in the mother turtle correlated with the development of more male offspring, and turtles exposed to both mercury and agricultural shade produced the most male offspring."These unexpected interactions raise new, serious concerns about how wildlife respond to environmental changes due to human activities. They also add an extra layer of complexity to current projections of climate change," said Hopkins.A general best practice for conservation management, according to the researchers, is to incorporate periods of uncultivation for fields in areas known to support a high number of turtle nests. For species of special concern, such as the wood turtle in Virginia, working with landowners to rotate periods of crop growth, implement predator guards, and exercise caution with machinery near identified nests could prevent over-shading and nest damage.
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Endangered Animals
| 2,018 |
April 23, 2018
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https://www.sciencedaily.com/releases/2018/04/180423135043.htm
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'Environmental DNA' used to identify killer whales in Puget Sound
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When endangered killer whales swim through the sheltered waters of Puget Sound, they leave behind traces of "environmental DNA" that researchers can detect as much as two hours later, a new study has found.
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The findings, published today in the journal "If we can replicate this in the open ocean, it will be a game-changing advance," said Scott Baker, associate director of the Marine Mammal Institute at Oregon State University and lead author on the study. "It's been well-established that you can follow a whale and capture some of its fecal plume before it dissipates. But this is completely different.""We were able to capture DNA in the water two hours after the whales had passed through, thanks to advances in genomic technology."Baker said that in addition to the obvious bodily functions of whales, the environmental DNA is probably shed from the spout or 'blow' and from skin."Whales slough a lot of skin," he said.To test their methodology, the researchers traveled to the San Juan Islands -- a site known as a regular seasonal habitat of the endangered 'southern resident' community of killer whales. They collected water samples from 200 meters behind whales on 25 separate encounters then remained in place -- drifting with the tides -- after the killer whales moved on. They were able to capture environmental DNA in 68 percent of those encounters and it persisted up to two hours in some encounters."On a couple of occasions, we drifted up to five kilometers, so there was a lot of water movement -- and we still got eDNA," Baker said.The ability to extract DNA from the water has several implications, the researchers note. It provides a new tool to complement acoustic and visual surveys to identify whale species and habitat. It may provide information about the origin of the whales -- the southern resident community of orcas in Puget Sound, for example, has a distinct DNA barcode from other populations. And it could help researchers locate rare or "cryptic" species of whales."If this method works in the open ocean, which we still have to test, it will be a powerful tool," Baker said. "There are 23 species of beaked whale and some of them have never been seen alive. They have only been identified through skeletal remains. And four of those species were identified in the last decade, so there may be more out there."The researchers say that environmental DNA is probably too fragmented to provide information about the health, sex identification or individual identification of the whales -- at least, for now. "Technology is improving rapidly, so it may be a matter of time," Baker said. "And, of course, expense -- especially for research in the open ocean."
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Endangered Animals
| 2,018 |
April 19, 2018
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https://www.sciencedaily.com/releases/2018/04/180419172701.htm
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Museum researchers rediscover animal not seen in 30 years
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Researchers from the San Diego Natural History Museum (The Nat) and the non-profit organization Terra Peninsular A.C. have rediscovered the San Quintin kangaroo rat (
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The San Quintin kangaroo rat was last seen in 1986, and was listed as endangered by the Mexican government in 1994. It was held as an example of modern extinction due to agricultural conversion. In the past few decades, San Quintin, which lies 118 miles south of Ensenada, has become a major agricultural hub, converting huge areas of native habitat into fields and hot houses for tomatoes and strawberries.Despite active searches and monitoring over the years, there had been no sign of the animal until this past summer, when Museum Mammalogist Scott Tremor and Research Associate Sula Vanderplank were in the field conducting routine monitoring of small mammal communities. Having read the field notes of the person who had seen it decades ago, they were aware of its former occurrence in the area, but were amazed to find four individuals by using traditional field techniques and live traps.This animal is about 5 inches in length with a tufted tail. It is an herbivore that lives in arid lowlands and gets its name from its large, powerful hind feet that propel the animal in large bounds (like a kangaroo). It is larger than other kangaroo rats in the region, and is feistier than its relatives."Not only is this discovery a perfect example of the importance of good old-fashioned natural history field work, but we have the opportunity to develop a conservation plan based on our findings," said Tremor. "The ability to take our research and turn it into tangible conservation efforts is thrilling. It is a commitment to preserving the uniqueness of the Baja California Peninsula."The discovery will be highlighted in an article by Tremor, Vanderplank, and Dr. Eric Mellink of the Center for Scientific Research and Higher Education of Ensenada, Baja California (CICESE) in the scientific journal Since the initial discovery, the San Quinton kangaroo rat has been found to also persist inside the Valle Tranquilo Nature Reserve just south of San Quintín, which is owned and managed by the local non-profit organization Terra Peninsular A.C. This reserve is recognized as an area voluntarily destined for conservation by the National Commission of Natural Protected Areas (CONANP) and will protect the future of the species into perpetuity.The Nat will work with Terra Peninsular and Dr. Exequiel Ezcurra, director of the University of California Institute for Mexico and the United States (UC MEXUS), on a conservation plan for the small mammal communities of the area, with an emphasis on the San Quintin kangaroo rat."Terra Peninsular has been monitoring the nature reserves looking for this species. You can't imagine how happy we are to find out that after all these efforts and with the help of The Nat we can be part of this rediscovery and continue working on its protection," said Jorge Andrade, adaptive manager coordinator at Terra Peninsular, who has also been involved in the project. "It's very gratifying for us to think that the San Quintin kangaroo rat persists in the area to some extent, thanks to the efforts of the staff, board members, and associated researchers of our organization."This plan, which is made possible with critical support from The JiJi Foundation Fund at the International Community Foundation, will be developed cooperatively with a working group created by Terra Peninsular and composed of local authorities, academic institutions and staff members. It will be written in both English and Spanish, will include restoration strategies, habitat improvements, molecular analysis of population health, land protection strategies and outreach and educational materials, and will identify key concerns for the future of the species.The Museum's research department, the Biodiversity Research Center of the Californias, conducts field explorations and engages in collections-based research to document and conserve our region's natural history and biodiversity. This is the third mammal that was thought to be extinct that museum staff have rediscovered in the Baja California Peninsula in the recent past: others include the high elevation California vole (Microtus californicus huperuthrus) and the round-tail ground squirrel (Xerospermophilus tereticaudus apricus)."These rediscoveries speak to hope and resilience in a changing world," said Vanderplank, who is also a science advisor at Terra Peninsular. "We are learning so much about this animal and its ecology, and we're delighted to know that it is permanently protected in the Valle Tranquilo Nature Reserve."
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Endangered Animals
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April 19, 2018
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https://www.sciencedaily.com/releases/2018/04/180419141536.htm
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Unprecedented wave of large-mammal extinctions linked to prehistoric humans
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<em>Homo sapiens</em>
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Elephant-dwarfing wooly mammoths, elephant-sized ground sloths and various saber-toothed cats highlighted the array of massive mammals roaming Earth between 2.6 million and 12,000 years ago. Prior research suggested that such large mammals began disappearing faster than their smaller counterparts -- a phenomenon known as size-biased extinction -- in Australia around 35,000 years ago.With the help of emerging data from older fossil and rock records, the new study estimated that this size-biased extinction started at least 125,000 years ago in Africa. By that point, the average African mammal was already 50 percent smaller than those on other continents, the study reported, despite the fact that larger landmasses can typically support larger mammals.But as humans migrated out of Africa, other size-biased extinctions began occurring in regions and on timelines that coincide with known human migration patterns, the researchers found. Over time, the average body size of mammals on those other continents approached and then fell well below Africa's. Mammals that survived during the span were generally far smaller than those that went extinct.The magnitude and scale of the recent size-biased extinction surpassed any other recorded during the last 66 million years, according to the study, which was led by the University of New Mexico's Felisa Smith."It wasn't until human impacts started becoming a factor that large body sizes made mammals more vulnerable to extinction," said the University of Nebraska-Lincoln's Kate Lyons, who authored the study with Smith and colleagues from Stanford University and the University of California, San Diego. "The anthropological record indicates that "From a life-history standpoint, it makes some sense. If you kill a rabbit, you're going to feed your family for a night. If you can kill a large mammal, you're going to feed your village."By contrast, the research team found little support for the idea that climate change drove size-biased extinctions during the last 66 million years. Large and small mammals seemed equally vulnerable to temperature shifts throughout that span, the authors reported."If climate were causing this, we would expect to see these extinction events either sometimes (diverging from) human migration across the globe or always lining up with clear climate events in the record," said Lyons, assistant professor of biology at Nebraska. "And they don't do either of those things."The team also looked ahead to examine how potential mammal extinctions could affect the world's biodiversity. To do so, it posed a question: What would happen if the mammals currently listed as vulnerable or endangered were to go extinct within the next 200 years?In that scenario, Lyons said, the largest remaining mammal would be the domestic cow. The average body mass would plummet to less than six pounds -- roughly the size of a Yorkshire terrier."If this trend continues, and all the currently threatened (mammals) are lost, then energy flow and taxonomic composition will be entirely restructured," said Smith, professor of biology at New Mexico. "In fact, mammalian body size around the globe will revert to what the world looked like 40 million years ago."Lyons said that restructuring could have "profound implications" for the world's ecosystems. Large mammals tend to be herbivores, devouring large quantities of vegetation and effectively transporting the associated nutrients around an ecosystem. If they continue to disappear, she said, the remaining mammals would prove poor stand-ins for important ecological roles."The kinds of ecosystem services that are provided by large mammals are very different than what you get from small mammals," Lyons said. "Ecosystems are going to be very, very different in the future. The last time mammal communities looked like that and had a mean body size that small was after the extinction of the dinosaurs."What we're doing is potentially erasing 40 to 45 million years of mammal body-size evolution in a very short period of time."Smith and Lyons authored the study with Jon Payne of Stanford University and Rosemary Elliott Smith from the University of California, San Diego. The team received support from the National Science Foundation.
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Endangered Animals
| 2,018 |
April 19, 2018
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https://www.sciencedaily.com/releases/2018/04/180419130945.htm
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Small changes in rainforests cause big damage to fish ecosystems
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Freshwater fish diversity is harmed as much by selective logging in rainforests as they are by complete deforestation, according to a new study.
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Researchers had expected the level of damage would rise depending on the amount of logging and were surprised to discover the impact of removing relatively few trees.There are many types of logging that occur in rainforests, from 'selective logging' -- only taking certain species -- to complete logging and the transformation of the rainforest to oil-palm plantations.Different types of animals react to these changes in often complex ways. However, a new study published today in The authors of the paper say the result suggests a rethink in how freshwater ecosystems are protected in these forests.Lead author Clare Wilkinson, from the Department of Life Sciences at Imperial, said: "That such a small change can impact fish biodiversity is shocking and worrying. We expected to see a gradient from least affected in the selectively logged areas, to heavily impacted for the streams in oil palm plantations. Instead, we saw almost the same level of fish biodiversity loss in all altered environments."The team sampled 23 streams in Borneo as part of the SAFE (Stability of Altered Forest Ecosystems) Project, which investigates environmental changes across a gradient from primary forest to oil palm plantation.They found that fish diversity was decreased in all logged areas compared to within virgin forest, and that the time since logging did not affect the level of change. All logged regions suffered similar levels of losses irrespective of whether only select trees were taken or all of them, or whether the logging was recent or further in the past.Researchers believe the reasons for these dramatic changes are likely to be down to a range of factors that affect stream habitats when trees are lost. Trees provide shade, creating cooler patches of stream that many fish need to spawn. Older, taller trees provide more of this shade, but they are the ones usually removed in selective logging. Leaf litter from these trees also helps to keep the streams cool and to concentrate food sources.The loss of trees also increases soil erosion, meaning banks are more susceptible to collapse and more sediment ends up in the stream. This had the effect of making streams shallower and wider, limiting the types of species that can use the habitat.For oil palm plantations to be labelled 'sustainable, they must include a riparian zone -- a buffer of forest land immediately bordering streams -- of at least 30 metres. However, in none the streams sampled in oil palm areas in this study, did the presence of a 30 metre riparian zone reduce the damage to fish biodiversity.Wilkinson said: "The freshwater fish in these streams are a food source for local people, so maintaining biodiversity is important. Our study suggests that current protections are not good enough in that they do not prioritise conserving intact forest, and are not sufficient to protect fish in more altered environments."
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Endangered Animals
| 2,018 |
April 18, 2018
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https://www.sciencedaily.com/releases/2018/04/180418144728.htm
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New ancestor of modern sea turtles found in Alabama
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A sea turtle discovered in Alabama is a new species from the Late Cretaceous epoch, according to a study published April 18, 2018 in the open-access journal
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Modern day sea turtles were previously thought to have had a single ancestor of the of the The researchers identified some of the Alabama fossils as representing a new These findings extend the known evolutionary history for theDrew Gentry says: "This discovery not only answers several important questions about the distribution and diversity of sea turtles during this period but also provides further evidence that Alabama is one of the best places in the world to study some of the earliest ancestors of modern sea turtles."
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Endangered Animals
| 2,018 |
April 18, 2018
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https://www.sciencedaily.com/releases/2018/04/180418141338.htm
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How well does the greater sage grouse habitat protects other species?
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Researchers in the University of Wyoming's Department of Zoology and Physiology and Program in Ecology discovered that size does matter -- as it pertains to the effectiveness of secondary species' wildlife protection relative to the size of a wildlife reserve set aside for an umbrella species.
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The umbrella species concept is defined as multiple wildlife species being indirectly protected under the umbrella of a reserve created to enhance conservation for one species -- in this case, the greater sage grouse in Wyoming. The research group investigated two potential mechanisms -- reserve size and species similarity -- underlying the concept's successful application. Larger alternative reserves serve as better umbrellas but, regardless of reserve size, not all species received equal protection, the study determined."This study provides us a better understanding of which species might fall through the cracks, and which may need targeted attention for their conservation," says Anna Chalfoun, a UW associate professor of zoology and an assistant unit leader for the Wyoming Cooperative Fish and Wildlife Research Unit."I was surprised at the findings. The longtime assumption is that what's good for the grouse is good for any other species living in sagebrush country," says Jason Carlisle, a Ph.D. student in UW's Program in Ecology from 2011-17 who led the study. "Sage grouse are often the flagship species in the ecosystem. But, when examining how well the protected area established for sage grouse covers other species that depend on sage grouse habitat, it leaves a lot to be desired."Carlisle was lead author and Chalfoun a co-author of a paper, titled "Identifying Holes in the Greater Sage-Grouse Conservation Umbrella," that was published March 30 in the online version of Douglas Keinath, formerly the lead vertebrate zoologist with the Wyoming Natural Diversity Database at UW; and Shannon Albeke, a research scientist/eco-informaticist in the Wyoming Geographic Information Science Center, were co-authors of the paper. Carlisle and Keinath also were part of the Wyoming Cooperative Fish and Wildlife Research Unit. The project was funded by a state wildlife grant from the Wyoming Game and Fish Department."When you hear people generally talking about sage grouse, whether it be land managers or politicians, they oftentimes are already making an assumption that sage grouse, as an umbrella species, is benefiting other species," Chalfoun says. "But, that assumption had not been critically tested."Until now.The umbrella species concept is one surrogate species strategy in which a species with large area requirements -- such as the greater sage grouse -- is provided sufficient protected habitat. In turn, that can provide protection of many other species in the same area. The main advantage of this strategy is the potential to conserve numerous species without extensive, individual consideration for each species, Chalfoun says.Carlisle described the concept as such: "The more umbrella you pop up, the more coverage you'll get from rain."Greater sage grouse are listed as endangered in Canada under the Federal Species at Risk Act. Each of the 11 states, including Wyoming, and two Canadian provinces where greater sage grouse live has a strategic plan to manage the species. Many, like in Wyoming, focus on government-established reserves, called "core areas," that are prevalent throughout the state, Chalfoun says. In 2015, the U.S. Fish and Wildlife Service determined an endangered species listing for greater sage grouse was not warranted in Wyoming or elsewhere."The Wyoming politicians and wildlife managers had the foresight to implement the core-area strategy," Chalfoun says. "Certainly, as a result of that, it has resulted in a lot less loss and fragmentation of Wyoming's sagebrush habitat."A primary reason Wyoming was a good place for this study is that the state is home to approximately 37 percent of the remaining greater sage grouse in the world, says Carlisle, originally from Payson, Utah."Wyoming is going to be critical. Wyoming has a strong history in protecting sage grouse," he says. "This is an opportunity to build on that and to look for what sage grouse management is going to mean for other species."Carlisle spent the bulk of his time crunching the numbers based on maps compiled by the Wyoming Natural Diversity Database. In what he termed "a poor man's supercomputer," Carlisle used about a dozen desktop computers in the Wyoming Geographic Information Science Center lab that ran simultaneously 24/7 for about a month during one summer. The computers were used to create 80 simulated reserves of various sizes and calculate the overlap they would provide the wildlife species.The established umbrella reserve, a sagebrush-steppe ecosystem in Wyoming, protected 82 percent of the state's greater sage grouse population and 0-63 percent of the habitat of the background species studied. The established reserve outperformed equally sized, simulated reserves for only 12 of the 52 background species of wildlife listed in the State Wildlife Action Plan as "species of greatest conservation need." These species were associated with vegetation communities where there are greater sage grouse, Chalfoun says.The dozen species that had the most habitat covered by the umbrella reserve were the Columbian sharp-tailed grouse, pygmy rabbit, sagebrush sparrow, greater short-horned lizard, great basin spadefoot (a toad), black-footed ferret, Idaho pocket gopher, olive-backed pocket mouse, sage thrasher, great basin pocket mouse, ferruginous hawk and the mountain plover."The species that benefited the most were the ones most similar to the sage grouse -- other birds," Chalfoun says of the established reserve.These species include avian species; those highly associated with sagebrush plant communities; and those with widespread habitat, the paper says.Carlisle agrees that other birds fared best under the umbrella species reserve. However, he also pointed to the state reptile, the greater short-horned lizard, as "a good news story." Core sage grouse habitat protected 46 percent of the habitat where the lizards dwell, he says. This was 12 percent higher than the computer simulation results.In contrast, the habitat of species with restricted distributions, particularly combined with vegetation associations not closely matching the greater sage grouse, did not receive as much protection from the umbrella reserve. Some of these species included the spotted ground squirrel, dwarf shrew, prairie lizard and the plains pocket gopher.The Wyoming pocket gopher, which is only native to Wyoming and is roughly the size of a guinea pig, was a prime example of a secondary species that did not fare all that well under the umbrella of sage grouse habitat, Carlisle says."We found this core area for sage grouse covered about 20 percent of their (Wyoming pocket gophers') habitat in the state," he says. "Twenty percent is not a lot for these types of species. In the simulations we did, the simulated areas covered twice as much (Wyoming pocket gopher) habitat."The results suggest that wildlife managers should pay close attention to background species with limited habitat, particularly if their vegetation associations do not align closely with those of the umbrella species.The paper's findings concede whether conservation strategies based on umbrella species are effective at conserving background species because of the selected umbrella species, or because the strategies inherently involve protecting large areas remains an open question.Understanding which traits predispose background species to protection under an umbrella strategy will be important to the overall success of conservation based on the umbrella species concept, Chalfoun says."The point of this is we can't assume all types of species are benefiting merely because of sage grouse," Chalfoun says. "What might be ideal sagebrush for sage grouse might not be right for other species."
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April 18, 2018
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https://www.sciencedaily.com/releases/2018/04/180418092047.htm
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How to improve habitat conservation for migrating cranes
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Every year, North America's critically endangered Whooping Cranes travel back and forth along a 4,000-kilometer corridor linking their nesting grounds in Canada and their winter home in Texas. Habitat in their path through the northern Great Plains is being lost at an alarming rate to agriculture and other development, but the birds' widely dispersed movements make identifying key spots for protection a challenge. Now, researchers behind a new study from
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Researcher Neal Niemuth and his colleagues used a database of Whooping Crane sightings in the region since 1990 to examine cranes' habitat use in North and South Dakota. Analyzing the spatial patterns of the sightings, they found that Whooping Cranes prefer habitat that includes a mix of croplands and wetlands and are more attracted by a single large wetland basin than multiple smaller basins. Their results also show the effects of different conservation strategies across the region. East of the Missouri River, where efforts have been specifically targeted toward waterfowl conservation, lands under conservation management were more likely than other locations to be used by Whooping Cranes. West of the river, however, this was not the case.Niemuth and his colleagues hope that their model can help to guide the siting of new wind, oil, and electrical transmission infrastructure to minimize potential conflicts with Whooping Cranes, as well as identifying opportunities for wetland restoration. According to the article, approximately $50 million per year is spent for habitat protection in the region, with much funding coming from sales of Duck Stamps. Because of their endangered status, Whooping Cranes have always been a priority in the area, but the quality and resolution of existing tools for targeting conservation and avoiding conflicts were low. The model presented in this publication provides biological linkages and increased spatial resolution that will increase effectiveness of Whooping Crane conservation efforts."Research on Whooping Crane habitat use throughout the migration corridor is crucial in helping us ensure that we are restoring and protecting habitat for a growing population of Whooping Cranes in the right places," states Wade Harrell, the U.S. and Wildlife Service's Whooping Crane Recovery Coordinator. "It is positive to see that the prairie pothole habitat in the Dakotas that the U.S. Fish & Wildlife Service is actively protecting for breeding waterfowl is also benefiting endangered species like the Whooping Crane."
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April 16, 2018
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https://www.sciencedaily.com/releases/2018/04/180416105803.htm
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Dinosaurs ended -- and originated -- with a bang!
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It is commonly understood that the dinosaurs disappeared with a bang -- wiped out by a great meteorite impact on the Earth 66 million years ago.
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But their origins have been less understood. In a new study, scientists from MUSE -- Museum of Science, Trento, Italy, Universities of Ferrara and Padova, Italy and the University of Bristol show that the key expansion of dinosaurs was also triggered by a crisis -- a mass extinction that happened 232 million years ago.In the new paper, published today in Dinosaurs had originated much earlier, at the beginning of the Triassic Period, some 245 million years ago, but they remained very rare until the shock events in the Carnian 13 million years later.The new study shows just when dinosaurs took over by using detailed evidence from rock sequences in the Dolomites, in north Italy -- here the dinosaurs are detected from their footprints.First there were no dinosaur tracks, and then there were many. This marks the moment of their explosion, and the rock successions in the Dolomites are well dated. Comparison with rock successions in Argentina and Brazil, here the first extensive skeletons of dinosaurs occur, show the explosion happened at the same time there as well.Lead author Dr Massimo Bernardi, Curator at MUSE and Research associate at Bristol's School of Earth Sciences, said: "We were excited to see that the footprints and skeletons told the same story. We had been studying the footprints in the Dolomites for some time, and it's amazing how clear cut the change from 'no dinosaurs' to 'all dinosaurs' was."The point of explosion of dinosaurs matches the end of the Carnian Pluvial Episode, a time when climates shuttled from dry to humid and back to dry again.It was long suspected that this event had caused upheavals among life on land and in the sea, but the details were not clear. Then, in 2015, dating of rock sections and measurement of oxygen and carbon values showed just what had happened.There were massive eruptions in western Canada, represented today by the great Wrangellia basalts -- these drove bursts of global warming, acid rain, and killing on land and in the oceans.Co-author Piero Gianolla, from the University of Ferrara, added: "We had detected evidence for the climate change in the Dolomites. There were four pulses of warming and climate perturbation, all within a million years or so. This must have led to repeated extinctions."Professor Mike Benton, also a co-author, from the University of Bristol, said: "The discovery of the existence of a link between the first diversification of dinosaurs and a global mass extinction is important."The extinction didn't just clear the way for the age of the dinosaurs, but also for the origins of many modern groups, including lizards, crocodiles, turtles, and mammals -- key land animals today."
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Endangered Animals
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April 16, 2018
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https://www.sciencedaily.com/releases/2018/04/180416085940.htm
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A new hope: One of North America's rarest bees has its known range greatly expanded
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The
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In fact, the cuckoo bee -- which much like its feather-bearing counterpart does not build a nest of its own, but lays its eggs in those of other species instead -- is so rare that it was thought to have gone extinct until it was collected in Nova Scotia, Canada, in the early 2000s. As a result, the Recently, an individual reported from Alberta, Canada, brought new hope for the survival of the species. In addition to previously collected specimens from Ontario, this record greatly expands the known range of the cuckoo.Scientists Dr Cory S Sheffield, Royal Saskatchewan Museum, Canada, who was the one to rediscover the "extinct" species in Nova Scotia, and Jennifer Heron, British Columbia Ministry of Environment & Climate Change Strategy, present their new data, and discuss the conservation status of this species in their paper, published in the open access journal "This species has a very interesting biology," they say, "being a nest parasite -- or cuckoo -- of another group of bees that in turn have very specialized dietary needs."The hosts, bees of the genus "This level of co-dependence between flower, bee, and cuckoo bee, makes for a very tenuous existence, especially for the cuckoo," the authors comment. "The recent specimen from Alberta lets us know that the species is still out there, and is more widespread than we thought."In conclusion, the authors suggest that continuing to monitor for populations of rare bees, and documenting historic records, are crucial for conservation status assessments of at-risk species."
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Endangered Animals
| 2,018 |
April 12, 2018
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https://www.sciencedaily.com/releases/2018/04/180412141103.htm
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Genetic evidence that magnetic navigation guides loggerhead sea turtles
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New research from the University of North Carolina at Chapel Hill provides valuable insight into the navigation and nesting behaviors of loggerhead sea turtles that could inform future conservation efforts. Loggerhead sea turtles that nest on beaches with similar magnetic fields are genetically similar to one another, according to a new study by UNC-Chapel Hill biologists Kenneth J. Lohmann and J. Roger Brothers. The study will publish in the journal
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Key takeaways include:"Loggerhead sea turtles are fascinating creatures that begin their lives by migrating alone across the Atlantic Ocean and back. Eventually they return to nest on the beach where they hatched -- or else, as it turns out, on a beach with a very similar magnetic field," said Kenneth Lohmann, professor of biology in the College of Arts and Sciences at UNC-Chapel Hill. "This is an important new insight into how sea turtles navigate during their long-distance migrations. It might have important applications for the conservation of sea turtles, as well as other migratory animals such as salmon, sharks and certain birds."
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Endangered Animals
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April 12, 2018
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https://www.sciencedaily.com/releases/2018/04/180412141031.htm
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Animal images used in marketing may skew public perception about their survival risks
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Many of the world's most charismatic animal species -- those that attract the largest interest and deepest empathy from the public -- are at high risk of extinction in part because many people believe their iconic stature guarantees their survival.
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A new international study published today in The researchers used a combination of online surveys, school questionnaires, zoo websites and animated films to identify the 10 most charismatic animals. The top three were tigers, lions and elephants, followed by giraffes, leopards, pandas, cheetahs, polar bears, gray wolves and gorillas."I was surprised to see that although these 10 animals are the most charismatic, a major threat faced by nearly all of them is direct killing by humans, especially from hunting and snaring," said William Ripple, a distinguished professor of forest ecology at Oregon State University and a co-author on the study."This killing by humans seems sadly ironic to me, as these are some of our most beloved wild animals."Many of these animals are so frequently depicted in pop culture and marketing materials that they may constitute a deceptive "virtual population" that is doing better in the media than in nature, noted lead author Franck Courchamp of the University of Paris.The researchers found, for example, that the average French citizen will see more virtual lions through photos, cartoons, logos and brands in one month than there are wild lions left in West Africa."Unknowingly, companies using giraffes, cheetahs or polar bears for marketing purposes may be actively contributing to the false perception that these animals are not at risk of extinction, and therefore not in need of conservation," Courchamp said.In their paper, the researchers propose that companies using images of threatened species for marketing purposes provide information to promote their conservation, and perhaps part of their revenue for protection of the species.Endangered species conservation efforts are numerous, though splintered. The researchers note that 20 million Americans took to the streets in 1970 to demonstrate on the first Earth Day, but there hasn't been a similar mobilization for conservation since.Oregon State's Ripple said the concept of charismatic species is pervasive in conservation literature and the public may assume that efforts to ensure their survival are in place and successful."Even much of the literature emphasizes the need to go beyond charismatic species and focus on the lesser known ones," Ripple said. "The public may be taking for granted that we're doing all we can to save them, when we don't even know for certain how many elephants, gorillas, or polar bears exist in the wild."The status of most of the top charismatic species is cause for alarm, Ripple pointed out."The top 10 charismatic animals are all mammals and include some of the largest carnivores and largest herbivores in the terrestrial world," Ripple said. "The fact that humans are also large mammals might explain why the public has a strong affinity for these 10 mammals -- it seems like people also love large animals much more than small ones."Nearly half (48.6 percent) of all the non-teddy bear stuffed animals sold in the United States on Amazon were one of the 10 charismatic animals, while in France some 800,000 "Sophie the giraffe" baby toys were sold in 2010 -- more than eight times the numbers of giraffes living in Africa."The appearance of these beloved animals in stores, in movies, on television, and on a variety of products seems to be deluding the public into believing they are doing okay," Ripple said. "If we don't act in a concerted effort to save these species, that may soon be the only way anyone will see them."
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Endangered Animals
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April 11, 2018
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https://www.sciencedaily.com/releases/2018/04/180411145119.htm
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New method prioritizes species for conservation in the face of uncertainty
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A new way to prioritize species for conservation efforts outperforms other similar methods, according to research presented in
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The ongoing "sixth mass extinction," driven by human activity, threatens species around the world. A variety of different metrics have been used to prioritize species for conservation efforts, including the Evolutionarily Distinct and Globally Endangered (EDGE) metric, developed at the Zoological Society of London. EDGE ranks each species based on its relative contribution to the total evolutionary history of its taxonomic group, combined with its risk of extinction. More evolutionarily distinct species represent a greater amount of evolutionary history than species with many close relatives, meaning that their extinction results in a greater loss of biodiversity. However, a species' evolutionary distinctness can be difficult to determine if genetic sequencing data is unavailable.To address this issue, Gumbs and colleagues developed a new method to estimate evolutionary distinctness scores for "missing" species and correct the scores of their relatives. The researchers then compared their new method with two previously developed strategies for determining evolutionary distinctness to see how well they reproduced evolutionary distinctness scores for known species.The analysis showed that the new method gave the most accurate estimates of species' evolutionary distinctness scores. Its estimates differed from known scores by an average of 1 percent, while the two older methods' estimates differed from true scores by 31 and 38 percent. Using the new method, the researchers updated evolutionary distinctness scores and EDGE prioritization rankings for all tetrapods (four-footed animals), including the first ranking for reptiles. In the future, the new method promises to help researchers keep up with new genetic data and updated phylogenetic trees that could affect prioritization rankings.Rikki Gumbs says: "Using a novel method to incorporate species with no evolutionary data, we updated existing EDGE prioritisations for amphibians, birds and mammals, and created the first EDGE prioritisation for reptiles, including a Top 100 EDGE Reptile List to inform and inspire conservation efforts on some of the world's most unique, threatened and overlooked species."
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Endangered Animals
| 2,018 |
April 11, 2018
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https://www.sciencedaily.com/releases/2018/04/180411111027.htm
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Extensive seagrass meadows discovered in Indian Ocean through satellite tracking of green turtles
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Research led by Swansea University's Bioscience department has discovered for the first time extensive deep-water seagrass meadows in the middle of the vast Indian Ocean through satellite tracking the movement of green sea turtles.
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A new study by Swansea University and Deakin University academics, published in the recent This area lies in the heart of one of the world's largest Marine Protected Areas (MPAs) and the study involved the use of in-situ SCUBA and baited video surveys to investigate the day-time sites occupied by the turtles, resulting in the discovery of extensive monospecific seagrass meadows of These habitats are critically important for storing huge amounts of carbon in their sediments and for supporting fish populations.At three sites that extended over 128?km of the Great Chagos Bank, there was a high seagrass cover (average of 74%) at depths to 29 metres.The mean species richness of fish in the seagrass meadows was 11 species per site, with a mean average of 8-14 species across the aforementioned three sites.Results showed a high fish abundance as well as a large predatory shark recorded at all sites and given that the Great Chagos Bank extends over approximately 12,500?km and many other large deep submerged banks exist across the world's oceans, the results suggest that deep-water seagrass may be far more abundant than previously suspected.Reports of seagrass meadows at these depths with high fish diversity, dominated by large top predators, are relatively limited.Dr Nicole Esteban, a Research Fellow at Swansea University's Biosciences department, said: "Our study demonstrates how tracking marine megafauna can play a useful role to help identify previously unknown seagrass habitat."We hope to identify further areas of critical seagrass habitat in the Indian Ocean with forthcoming turtle satellite tracking research."Dr Richard Unsworth, from Swansea University's Biosciences department, said: "Seagrasses struggle to live in deep waters due to their need for high light, but in these crystal clear waters of Chagos these habitats are booming."Given how these habitats are threatened around the world it's great to come across a pristine example of what seagrass meadows should look like."This research was led by the Bioscience department at Swansea University, alongside the involvement of researchers at Deakin University.
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Endangered Animals
| 2,018 |
April 9, 2018
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https://www.sciencedaily.com/releases/2018/04/180409120437.htm
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Why the Tasmanian devil might be more susceptible to transmissible cancers
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Cancers that can jump from one animal to another of the same species are rare, but the endangered Tasmanian devil is doubly unlucky: in the last few decades, two transmissible cancers affecting them have been identified. A comparison of these two cancers, published April 9 in the journal
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Tasmanian devils, while relatively docile with humans, are known for biting each other on the face as they fight over mates and food. This is the route by which both cancers, which cause similar facial tumors before metastasizing, spread from devil to devil. But even though the cancers manifest similarly, they originated in two different individuals, probably years apart.There are only eight known naturally occurring transmissible cancers: one in dogs, two in Tasmanian devils, and five in various species of marine bivalves, so to see two such cancers appear in such a short time in a single species was quite surprising. "When the first one was discovered, we thought that transmissible cancers were extremely rare and that Tasmanian devils were just really unlucky to get this cancer," says senior researcher Elizabeth Murchison, a geneticist at the University of Cambridge who grew up in Tasmania. "But the emergence of the second one made us wonder whether Tasmanian devils might be particularly at risk for developing this kind of disease."It was also possible some sort of environmental or anthropogenic change affecting the devils might have made the emergence of these cancers more likely. To evaluate these hypotheses, the researchers conducted genetic and functional comparisons of the two devil cancers.They were unable to identify genomic markers of any viruses or external carcinogens, like UV light, that might have caused the cancers, although the researchers readily point out that there could be something they didn't test for or look for that does play a role. What they did find, however, was that the two cancers, despite originating in different individuals, had similar mutational processes and similar tissues of origin, and responded to similar drugs. "It really pointed to some kind of problem that the devils have with this kind of cell's regulation, which probably gives them a greater risk of developing this type of disease," Murchison says.And it might all come back to that biting behavior. The effective drugs that the researchers identified when they compared the cancers inhibit pathways normally involved in healing, suggesting that wound repair pathways might somehow be involved in the origin of the cancers. So the devils' frequent facial injuries could actually play a role in causing the cancer to arise, as well as providing a route by which the diseases can jump from host to host.Humans may have played a role, too. "When white people first settled in Tasmania, they'd hear these screams at night. And they thought there must be a devilish creature out there," says first author Maximilian Stammnitz. The settlers persecuted the devils, and the subsequent decline in their population probably further decreased the already low genetic diversity of the species. This is important, he says, because transmissible cancers need to escape the new host's immune system, just as any other foreign tissue transplant would in order to take hold. "Their immune systems may be less poised to detect foreign tumor cell grafts, compared to other species that have more genetic diversity." Furthermore, the changes to the landscape that have resulted from European settlement in Tasmania may have indirectly altered devil population dynamics and migration patterns, possibly creating conditions conducive for transmissible cancer emergence and spread.The effects of these cancers have been devastating, wiping out 90% of the devils in some parts of Tasmania and threatening the survival of the species. "As scavengers, they're an important placeholder in the ecosystem of the island. They're sort of the ecological clean-up service, so their absence is visible in the landscape," Stammnitz says. While conservation efforts are already underway, the researchers are optimistic that, with further research and testing, the drugs their comparison has identified -- which are currently used for precision cancer therapy in humans -- could provide another option for helping the devils.This research also has broader implications for our understanding of transmissible cancers. "Just in the last couple of years, we've gone from knowing of two transmissible cancers -- the dogs and the devils -- to eight. It's hinting at the possibility that perhaps transmissible cancers were not so well recognized before, and maybe they're more common than we previously thought," says Murchison.
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Endangered Animals
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April 6, 2018
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https://www.sciencedaily.com/releases/2018/04/180406085510.htm
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Climate change is wreaking havoc on delicate relationship between orchids and bees
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The first definitive demonstration of climate change upsetting the vital interdependent relationships between species has been revealed, thanks to a study led by the University of Sussex.
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Research led by Prof Michael Hutchings at the University of Sussex tracks how rising temperatures since the mid-17th century have wrecked a relationship, which relies on precision timing to succeed, between a rare orchid species and the Buffish Mining-bee which pollinates it.Prof Hutchings, Emeritus Professor in Ecology, said the climate is changing so rapidly that the early spider orchid cannot respond effectively, leaving this species, and probably many other plants with highly specialized pollination mechanisms, facing the threat of severe decline and possible extinction.Prof Hutchings said: "It is likely that many other species dependencies are also suffering from climate-induced changes to their life cycles. This study is, we believe, the best documentation we have as yet of such an effect and confirms with hard data the long-held concerns of ecologists. While this is especially bad news for the early spider orchid, the devastating impact of climate change is in all likelihood harming the delicate interdependent relationships of many species."The early spider orchid achieves pollination by emitting a scent that imitates that of a female Buffish Mining-bee. The smell fools male bees into attempting to mate (pseudocopulation) with the flower. In doing so, the male bee dislodges pollen masses from the flower. These pollen masses are then transported to different flowers when the bee next attempts pseudocopulation.Pollination depends not only on male bees emerging before female bees and before flowering, but also, crucially, on the orchid flowering before female bees emerge.However, rising temperatures have led to male bee flight, female bee flight and flowering all occurring earlier in the calendar year, but the timings of the three events are not changing at the same rate.This is causing an increasing frequency of years in which the sequence of events needed for successful pollination (male bee emergence before orchid flowering before female bee emergence) does not occur.For every 1 °C rise in spring temperature, the peak flying dates of male and female bees occur 9.2 and 15.6 days earlier in the year but the orchids' peak flowering advances by just 6.4 days.The study shows that, since the mid-seventeenth century, as recorded spring temperatures have gradually risen, the interval between male and female bees emerging from hibernation has decreased significantly.Most critically, however, higher spring temperatures now make female bees likely to achieve peak flying more than a week before peak orchid flowering date.Whereas peak flying date of female bees preceded peak orchid flowering in only 40% of the years between 1659 and 1710, this figure has risen to 80% in the years from 1961 to 2014.As female bees now take flight before the orchid flowers in almost every year, male bees will mate by preference with females rather than pseudocopulate with the orchid, simply because female bees are available as a better alternative when the orchid is flowering. Orchid pollination is therefore much less likely nowadays than when spring temperatures were lower, and it may fail completely in almost all years.Worryingly, the research, carried out with the University of East Anglia and the University of Kent and published in the Climate change, alongside loss of habitat, unsuitable grazing regimes, the orchid's already-inefficient pollination mechanism and its short life-span, has seen its range in the UK decline by at least 60% since 1930.But Prof Hutchings warns that unless the orchid undergoes rapid selection for earlier flowering following warm springs, it is likely that continued climate change will result in it always flowering after the emergence of female bees. He warns that a programme of hand pollination may be the only means to ensure the early spider-orchid remains a presence in the UK.He added: "Further studies are urgently required, on a wider range of species and in various ecological communities, to assess the potential for climate warming to cause disruption of vital life historical events where different species are dependent on each other."As well as posing problems for plants that depend on pollinators being available on particular dates, climate change could threaten many other ecological interdependencies, including birds depending on caterpillars being available as food immediately after hatching and insects needing specific nectar sources."
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Endangered Animals
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April 5, 2018
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https://www.sciencedaily.com/releases/2018/04/180405100145.htm
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The ban of the cave bear
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At 3.5 meters long and with a shoulder height of 1.7 meters, the cave bear was one of the giants of the Ice Age. Yet few appear to have survived until the last glacial maximum 24,000 to 19,000 years ago. Researchers from Germany, Italy and Canada have conducted analyses to find out what likely caused the extinction of these large herbivores. It is believed that the renewed cooling of the climate and hunting by humans ‒ added to the bears' purely vegetarian diet ‒ increased the pressure on this megafauna species. Professor Hervé Bocherens of the Senckenberg Center for Human Evolution and Palaeoenvironment at the University of Tübingen took part in the study, which examined cave bear bones using the latest methods. The results of the study have been published in
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Cave bears (In several regions of Europe, cave bears disappeared well before the start of the last glacial maximum. However, some cave bear populations seem to have survived until 24,000 years ago -- with one in northeastern Italy whose more recent dates suggest it was the last to die out. The researchers used bones from that location for the current study. They dated the bones using the latest methods and compared the bears' diet with that of older populations. They also looked for signs of hunting and butchery by humans.The new radiocarbon dating confirmed that these cave bears lived as late as 24,000 years ago, after the start of the last glacial maximum. The bones also revealed evidence of hunting and butchery by humans. Isotopic analyses showed that the bears still did not eat meat, despite the colder climate. Hervé Bocherens suggests this lack of adaptability and the pressures of hunting by humans may have increased the stress on the cave bears ‒ such that they could no longer survive in a harsher climate. "It was likely this combination of climatic and anthropogenic factors which led to their extinction," he says.
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Endangered Animals
| 2,018 |
April 5, 2018
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https://www.sciencedaily.com/releases/2018/04/180405095358.htm
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Diving deep into the blue whale genome reveals the animals’ extraordinary evolutionary history
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For the first time, scientists of the German Senckenberg Biodiversity and Climate Research Center, Goethe University and the University of Lund in Sweden have deciphered the complete genome of the blue whale and three other rorquals. These insights now allow tracking the evolutionary history of the worlds’ largest animal and its relatives in unprecedented detail. Surprisingly, the genomes show that rorquals have been hybridizing during their evolutionary history. In addition, rorquals seem to have separated into different species in the absence of geographical barriers. This phenomenon, called sympatric speciation, is very rare in animals. The study has just been published in
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Blue whales are the giants of the sea. With up to 30 meters (100 feet) long and weighing up to 175 tons, they are the largest animals that ever evolved on earth; larger even than dinosaurs. Short of becoming extinct due to whaling by the end of the 80s, currently the populations of the gentle giants are slowly recovering. Now new research highlights that the evolution of these extraordinary animals and other rorquals was also anything but ordinary.A research team led by Professor Axel Janke, evolutionary geneticist at the Senckenberg Biodiversity and Climate Research Center and Goethe University, has found that the rorquals, including the blue whale, mated across emerging species boundaries. “Speciation under gene flow is rare. Usually, species are assumed to be reproductively isolated because geographical or genetic barriers inhibits genetic exchange. Apparently however, this does not apply to whales”, explains Fritjof Lammers, co-lead-author of the study, Senckenberg Biodiversity and Climate Research Centre.Teaming up with cetacean specialist Professor Ulfur Arnason at University of Lund, Sweden, Lammers and his colleagues are the first to have sequenced the complete genome of the blue whale and other rorquals, including the humpback and the gray whale. For these migratory whales, geographical barriers do not exist in the vastness of the ocean, instead some rorquals differentiated by inhabiting different ecological niches. Cross-genome analyses now indicate that there are apparently no genetic barriers between species and that there has been gene flow among different rorqual species in the past.This is confirmed by spotting hybrids between fin and blue whales still to date, which have been witnessed and genetically studied by Professor Arnason. However, the researchers could not detect traces of recent liaisons between the two species in their genomes. This is probably because whale genomes are currently known only from one or two individuals.To track down the rorquals’ evolution, the scientists have applied so-called evolutionary network analyses. "In these analyses, speciation is not considered as a bifurcating phylogenetic tree as Darwin has envisioned it, but as an interwoven network. This allows us to discover hidden genetic signals, that otherwise would have stayed undetected", says Janke.Overall, the research also shows that the relationships among the rorqual species are more complicated than hitherto thought. So far, the humpback whale has been seen as an outsider among the rorquals because of its enormous fins. The genome reveals that this classification does match the evolutionary signals. The same is true for the gray whale, which was believed to be evolutionarily distinct from rorquals due to its appearance. Genomic analyses show however that gray whales are nested within rorquals. Gray whales just happened to occupy a new ecological niche by feeding on crustaceans in coastal oceanic waters."Our research highlights the enormous potential of genome sequencing to better understand biological processes and the fundamentals of biodiversity. It even reveals how population sizes of whales have changed during the last million years", summarizes Janke. Janke is one of the leading researchers at the Hessian LOEWE Research Centre for Translational Biodiversity Genomics (LOEWE-TBG). Launched in January 2018, LOEWE-TBG is set to systematically analyze complete genomes or all active genes. The research center is envisaged to do basic research with a strong emphasis on transferring knowledge to benefit the study of natural products and protect biodiversity.
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Endangered Animals
| 2,018 |
April 5, 2018
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https://www.sciencedaily.com/releases/2018/04/180405093241.htm
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Eating less enables lemurs to live longer
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Chronic caloric restriction consists in eating a reduced but balanced diet from early adult life onward. Previous research, into macaques in particular (which have an average lifespan of forty years), had already demonstrated its beneficial effect on the incidence of age-related pathologies. However, its positive effect on the lifespan of primates remained controversial. To study this question, the researchers focused on the grey mouse lemur, a small primate whose lifespan (around twelves years) makes it a very good model for the study of aging. Moreover, this small lemurid has many physiological similarities with humans.
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The scientists exposed a group of mouse lemurs to moderate chronic caloric restriction (30% fewer calories than their peers consuming a normal diet) from the outset of early adulthood (Restrikal cohort, see visuals below). They then considered their survival data as well as possible age-related alterations. The first result, after the experiment had been running for ten years, was that in comparison to the animals in the control group, the lifespan of those subject to caloric restriction increased by almost 50%. More specifically, their median survival is 9.6 years (compared to 6.4 years for the mouse lemurs in the control group). And, for the first time among primates, the scientists observed that the maximum lifespan had increased: almost a third of the calorie-restricted animals were still alive when the last animal in the control group died at the aged of 11.3 years.This beneficial effect was accompanied by the preservation of motor capacities, without any alteration to cognitive performance, and a reduction in the incidence of pathologies usually associated with aging, such as cancer or diabetes. The calorie-restricted mouse lemurs present the morphological characteristics of a younger animal. Furthermore, brain imaging data for these very elderly animals shows a slight loss of grey matter (neuronal cell bodies), an effect that the researchers have not yet explained, as well as significantly slowed atrophy of white matter (the neuronal fibers connecting different areas of the brain).The results indicate that chronic caloric restriction is currently the most effective way to extend maximum lifespan and delay the aging process in a non-human primate. The next step for the scientists is to associate chronic caloric restriction with another study parameter, such as physical exercise, in an attempt to further extend the upper limits of lifespan.
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Endangered Animals
| 2,018 |
April 5, 2018
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https://www.sciencedaily.com/releases/2018/04/180405101749.htm
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Freezing breakthrough offers hope for African wild dogs
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James Cook University researchers in Australia have helped develop a new way to save endangered African wild dogs.
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Dr Damien Paris and PhD student Dr Femke Van den Berghe from the Gamete and Embryology (GAME) Lab at James Cook University, have successfully developed a sperm freezing technique for the species (The highly efficient pack hunters have disappeared from most of their original range across sub-Saharan Africa due to habitat destruction, human persecution and canine disease, leaving less than 6,600 animals remaining in the wild.Dr Paris said population management and captive breeding programs have begun, but there is a problem."One goal of the breeding programs is to ensure the exchange of genetic diversity between packs, which is traditionally achieved by animal translocations. But, due to their complex pack hierarchy, new animals introduced to an existing pack are often attacked, sometimes to the point of being killed," he said.Dr Paris said the new sperm freezing technique could now be combined with artificial insemination to introduce genetic diversity into existing packs of dogs, without disrupting their social hierarchy.Working with international canine experts Associate Professor Monique Paris (Institute for Breeding Rare and Endangered African Mammals), Dr Michael Briggs (African Predator Conservation Research Organization), and Professor. Wenche Farstad (Norwegian University of Life Sciences), Dr Paris and Dr Van den Berghe collected and froze semen from 24 males across 5 different packs using the new formulation.After thawing sperm to test their survival, the team discovered most sperm remained alive, appeared normal and continued to swim for up to 8 hours."Sperm of this quality could be suitable for artificial insemination of African wild dog females to assist outbreeding efforts for the first time," said Dr Van den Berghe.Dr Paris said he is determined the findings will reach zoo and wildlife managers in order to maximise the uptake of these techniques and develop a global sperm bank for the species.As part of these efforts, the team have also presented these results at the International Congress on Animal Reproduction (France), African Painted Dog Conference (USA), and European Association of Zoo and Aquaria Conference (Netherlands).
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Endangered Animals
| 2,018 |
April 4, 2018
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https://www.sciencedaily.com/releases/2018/04/180404182504.htm
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Lizards, mice, bats and other vertebrates are important pollinators, too
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Bees are not the only animals that carry pollen from flower to flower. Species with backbones, among them bats, birds, mice, and even lizards, also serve as pollinators. Although less familiar as flower visitors than insect pollinators, vertebrate pollinators are more likely to have co-evolved tight relationships of high value to the plants they service, supplying essential reproductive aid for which few or no other species may substitute.
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In plants known to receive flower visitations from vertebrates, fruit and seed production drops 63 percent, on average, when the larger animals, but not insects, are experimentally blocked from accessing the plants, ecologists report in the March cover study for the Ecological Society of America's journal Fabrizia Ratto and colleagues reviewed 126 such animal exclusion experiments to get an idea of how dependent wild plants are on animals with backbones for reproduction. The researchers selected published studies that quantified pollination through the subsequent growth of fruit or seeds.The exclusion of bat pollinators had a particularly strong effect on their plant consorts, reducing fruit production by 83 percent, on average. Bats pollinate about 528 plant species worldwide, including crops like dragon fruit, African locust beans, and durian, Southeast Asia's "King of Fruits." The authors speculate that chiropterophilous, or bat-pollinated, plants are unusually dependent on just a few, related species to carry their pollen.Many bat species have coevolved intimate interdependencies with the plants that feed them in exchange for pollen transport. Among them, blue agave (Loss of pollination by vertebrates had a higher impact in the tropics, where the study found a 71 percent decline in fruit or seed production. This higher impact may reflect the higher degree of customization for specific pollinators, the authors say. Like the agave cacti, specialized plants that rely on a small number of species of animal helpers for their reproductive success are more vulnerable to disruption.Non-flying mammals are also pollinators, visiting at least 85 plant species worldwide. Ruffed lemurs (Over 920 bird species pollinate plants, forming the largest contingent of the vertebrate pollinators and pollinating about 5 percent of plant species in most regions. The reliance of plants on birds tends to be higher on islands, where birds typically pollinate 10 percent of the local flora. Perhaps most surprisingly, some lizard species are also pollinators, especially on islands.The distribution and health of vertebrate pollinators is well documented compared to insect species, allowing, the authors argue, for targeted conservation efforts. As pollinating bird and mammal species fall under increasing pressure from habitat conversion to agriculture needs, fire, hunting, and invasions of non-native species, their plant companions and other species that feed on fruits and seeds are also at risk.
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Endangered Animals
| 2,018 |
April 4, 2018
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https://www.sciencedaily.com/releases/2018/04/180404163638.htm
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Rare coastal martens under high risk of extinction in coming decades
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The coastal marten, a small but fierce forest predator, is at a high risk for extinction in Oregon and northern California in the next 30 years due to threats from human activities, according to a new study.
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The study, published today in the online journal "Martens are like the river otters of the woods," Moriarty said. "But they can be vicious little critters, too. When you capture one and it's growling at you from inside a cage, there is no mistaking its intent. They're the size of kittens and act like they'll attack a pit bull."Some threats to coastal martens include trapping and being hit by cars, said Moriarty, an Oregon State University graduate now with the U.S. Department of Agriculture Forest Service Pacific Northwest Research Station. Martens are trapped for their fur throughout Oregon with no bag limit."This study provides the most conclusive evidence yet of risk to a coastal marten population," she said. "It's the only robust population estimate of a marten population in the Pacific states."Martens are rare in the coastal forests of Oregon and northern California. A different subspecies of martens thrives in the high elevation forests within the Cascade mountains. Martens resemble a cross between a fox and a mink, with bushy tails and large paws with partially retractable claws. Coastal martens were petitioned for listing under the U.S. Endangered Species Act in 2010, but withdrawn for consideration by the fish and wildlife service in 2015. Last year, the U.S. District Court for Northern California denied the withdrawal, and the fish and wildlife service is now collecting information on marten populations for a decision to be made in October."This marten population is now so small that it is in imminent danger of extinction, which would leave martens without a source population to recolonize the central and northern coast of Oregon," said Taal Levi, a professor of wildlife biology in the Department of Fisheries and Wildlife in OSU's College of Agricultural Sciences and a co-author on the study.Martens once ranged throughout coastal forests throughout Oregon to the northern California wine country. Extensive surveys revealed that the coastal marten population is now restricted to two populations, one in southern Oregon and Northern California, and another small population in the Oregon Dunes National Recreation Area, west of U.S. Highway 101 in central Oregon.To determine how many martens are in the Oregon Dunes, the researchers live-trapped and attached radio collars to 10 adult martens (six females, four males) and set 31 remotely triggered cameras in the study area that could identify unique patterns on collars. Statistical models were then used to estimate the number of martens based on the frequency in which uniquely marked martens were seen on camera.Their population assessment revealed that the central Oregon population of coastal martens is likely fewer than 87 adults divided into two subpopulations separated by the Umpqua River. Using a population viability analysis, they concluded that the extinction risk for a subpopulation of 30 martens ranged from 32 percent to 99 percent.In the short term, limiting human-caused deaths of the coastal martens would have the greatest impact on the animal's survival, said Moriarty, who has studied the animals for several years. In the long term, the species requires more habitat, which perhaps could be accomplished by making the adjacent federal land in Siuslaw National Forest suitable for martens.OSU graduate Mark Linnell, the study's lead co-author, led the field research. Co-author David Green, research faculty in OSU's Institute for Natural Resources, created the model that estimated the population size. Levi conducted the population viability simulations.The study's survey research was funded by the USDA Forest Service Pacific Northwest Research Station, Siuslaw National Forest, and the U.S. Fish and Wildlife Service.
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Endangered Animals
| 2,018 |
April 3, 2018
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https://www.sciencedaily.com/releases/2018/04/180403140424.htm
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Astro-ecology: Saving endangered animals with software for the stars
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A collaboration between astrophysicists and ecologists at Liverpool John Moores University (LJMU) is helping to monitor rare and endangered species and stop poaching. Astrophysical software and techniques are applied to thermal infrared imagery captured by drones to automatically detect and identify animals -- even at night, when most poaching activity occurs. The drones can survey large areas of difficult terrain from above, allowing ecologists to access hard to reach areas and monitor wildlife without disturbing the animals. The project will be presented by Claire Burke at the European Week of Astronomy and Space Science (EWASS) in Liverpool on Tuesday, 3rd April.
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Burke explains: "With thermal infrared cameras, we can easily see animals as a result of their body heat, day or night, and even when they are camouflaged in their natural environment. Since animals and humans in thermal footage 'glow' in the same way as stars and galaxies in space, we have been able to combine the technical expertise of astronomers with the conservation knowledge of ecologists to develop a system to find the animals or poachers automatically."The project is based around machine-learning algorithms and astronomical detection tools developed through the open source software, Astropy. Following an initial pilot project to test the concept with infrared footage of cows and humans filmed by drone at a farm in the Wirral, the team at LJMU has worked with Knowsley Safari and Chester Zoo to build up libraries of imagery to train the software to recognise different types of animals in different types of landscape and vegetation. Now, the team is embarking on field tests with endangered species."We held our first field trial in South Africa last September to detect Riverine rabbits, one of the most endangered species of mammal in the world. The rabbits are very small, so we flew the drone quite low to the ground at a height of 20 metres. Although this limited the area we could cover with the drone, we managed five sightings. Given that there have only been about 1000 sightings of Riverine rabbits by anyone in total, it was a real success," says Burke.The team has developed software that models the effects of vegetation blocking body heat, allowing the detection of animals concealed by trees or leaves. The system is now being refined and upgraded to compensate for atmospheric effects, weather and other environmental factors. The technical aspects of the project will be presented at EWASS by Maisie Rashman on Wednesday 4th April."Humidity can be an issue, but our biggest problems occur when the temperature of the ground is very similar to that of the animal we are trying to detect," comments Rashman.The astro-ecologists face their next field challenges in May, looking for orangutans in Malaysia and spider monkeys in Mexico, followed in June by a search for river dolphins in Brazil."Our aim is to make a system that is easy for conservationists and game wardens to use anywhere in the world, which will allow endangered animals to be tracked, found and monitored easily and poaching to be stopped before it happens," says Burke.
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Endangered Animals
| 2,018 |
April 2, 2018
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https://www.sciencedaily.com/releases/2018/04/180402160851.htm
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Digital life team creates animated 3-D models of sea turtles from live specimens
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The Digital Life team at the University of Massachusetts Amherst, creators of an online catalog of high-resolution, full-color 3D models of living organisms, announce today that they have released two new, online full-color animated models of a loggerhead and a green sea turtle through a collaboration with sea turtle rescue and research institutions.
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In collaboration with the Loggerhead Marinelife Center (LMC) of Juno Beach, Florida, Inwater Research Group of Jensen Beach, Florida, and Jeanette Wyneken of Florida Atlantic University, Digital Life's photographer Christine Shepard captured photographs of live sea turtles using the Beastcam technology, a custom multi-camera system created by biologist Duncan Irschick's laboratory at UMass Amherst for live animal 3D image capture.The Digital Life team, with volunteer 3D artists Jer Bot and Johnson Martin created the animated sea turtles using software such as Capturing Reality and Blender and a process called photogrammetry, in which multiple still photos are integrated to create lifelike 3D meshes with photographic colors.Other research partners on the sea turtle project include biologist Annabelle Brooks of the Cape Eleuthera Institute, Bahamas, and the Center for Evolutionary Materials at UMass Amherst, home of the Digital Life Project. Today's launch also includes a Digital Life Project sea turtle blog and web page describing the project in detail.Irschick, co-founder and director of the Digital Life project, says, "The value of these models is substantial, and includes both scientific and educational uses. To our knowledge it's the first time that 3D models of live sea turtles have been created from live animals."Photographer Shepard adds, "The models can be downloaded and 3D printed, such as for classroom use. These models can be used by scientists in a computer modeling environment for testing models of migration in sea turtles, or to test different net designs to avoid trapping sea turtles. They can also be used in VR or game-like educational environments, and are available at no cost to educators, scientists, conservationists and others for creative or nonprofit use on the Digital Life website."The animators spent hundreds of hours animating the 3D turtle models in a format that may be used for VR, film or game applications, among others, Irschick says. Bot, who animated a subadult green sea turtle from LMC nicknamed Scallywag, says he was immediately drawn into animal's intricacies.Scallywag was found missing one front flipper and floating in the water at Blowing Rocks Preserve after suffering from an apparent shark attack. Bot says, "Creating the animal with all its scars was an artistic and technical challenge, but we feel that we were able to reproduce this animal faithfully."The other sea turtle modeled so far for Digital Life is Shelly, an adult loggerhead recovered from a power plant by the Inwater research group. Irschick says the artists consulted closely with veterinarian Dr. Charles Manire from LMC and sea turtle biologist Jeanette Wyneken to accurately reconstruct the body shape and limb movements during swimming. Eventually, he adds, he and his team hope to make animated 3D models of all seven sea turtle species in the coming year, adding the leatherback, hawksbill, Kemp's ridley, olive ridley and flatback.LMC is a nonprofit sea turtle hospital that promotes conservation of ocean ecosystems with a focus on threatened and endangered sea turtles. In addition to its hospital, it has a research laboratory, educational exhibits and aquariums. All marine turtle images acquired in Florida for this work were obtained with the approval of the U.S. Fish and Wildlife Service and the Florida Fish and Wildlife Conservation Commission (FWC) under conditions not harmful to marine turtles, while conducting authorized conservation activities pursuant to FWC MTP-17-086 or MTP-17-125, the researchers state.
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Endangered Animals
| 2,018 |
March 30, 2018
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https://www.sciencedaily.com/releases/2018/03/180330105803.htm
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Proposed border wall will harm Texas plants and animals, scientists say
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In the latest peer-reviewed publication on the potential impacts of a border wall on plants and animals, conservation biologists, led by a pair of scientists from The University of Texas at Austin, say that border walls threaten to harm endangered Texas plants and animals and cause trouble for the region's growing ecotourism industry.
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In a letter publishing Monday in "Up to now, the wall has either gone through cities or deserts. This is the Rio Grande we're talking about here. It's totally different," Fowler said. "We have high biodiversity because of the river and because Texas extends so far south. I and other Texas biologists are very concerned about the impact this will have on our rich natural heritage."Based on a scientific literature review of 14 other publications, including some that looked at effects of existing walls and fences on the border, the authors outlined several concerns about the proposed wall, including habitat destruction and degradation caused by the construction of the wall and the roads on either side of the wall. Of particular concern is damage to Tamaulipan thornscrub, a once abundant and now increasingly rare ecosystem in South Texas. Many South Texas organisms depend on this ecosystem, but it's slowly disappearing as cities, farms and ranches displace the thornscrub. The living things that depend on it would lose access to some of the last remaining patches in Texas if the wall were built, Fowler said.A wall would also affect other species. The endangered wildflower Zapata bladderpod grows exactly where the barriers are proposed to be built, as does the threatened whiskerbush cactus. The ocelot, a small native wildcat listed as an endangered species, has already suffered from severe habitat loss; the Texas Parks and Wildlife Department estimates there are no more than 120 left in Texas, and scientists worry that the wall would further deplete their numbers. With habitat fragmentation, the wall could cut off ocelot, as well as black bear, populations in Texas and Mexico from other members of their species, leaving some populations too small to persist. There would be further damage to plants if the pollinators and seed-dispersing animals that plants depend on could not cross the barrier.Scientists also expressed concern about another aspect of the project. Because the wall will probably not be built in the flood plain of the Rio Grande, it will have to be set back from the river, sometimes by more than a mile. This has the potential to damage the valuable riparian forest ecosystem along the river, cutting off organisms that need to get to the river and preventing people from accessing several wildlife refuges along the river used for ecotourism."Even small segments of new wall on federal lands will devastate habitats and local recreation and ecotourism," said Keitt, also a professor of integrative biology.The Lower Rio Grande River Valley is currently a top destination for birdwatchers because rare tropical birds such as the green jay and the Altamira oriole are among those that frequent the area. A 2011 study from Texas A&M University estimated that ecotourism, mostly from birdwatchers, generated more than $344 million in economic activity in the Lower Rio Grande Valley alone."If ecotourism declines significantly because access to preserves has been impeded, there may be negative economic impacts on the region," the letter states. "On the other hand, if the barriers are not far enough from the river, they may trap wildlife escaping from floods, and may even act as levees, which tend to increase downstream flooding."Scientists also expressed concern about the project being exempt from environmental review requirements."Negative impacts could be lessened by limiting the extent of physical barriers and associated roads, designing barriers to permit animal passage and substituting less biologically harmful methods, such as electronic sensors, for physical barriers," the letter states.Olivia Schmidt, also of UT Austin, Martin Terry of Sul Ross State University and Keeper Trout of the Cactus Conservation Institute are also authors of the letter.
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Endangered Animals
| 2,018 |
March 28, 2018
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https://www.sciencedaily.com/releases/2018/03/180328130728.htm
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Turtle shells help decode complex links between modern, fossil species
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Imagine that Labradors and golden retrievers died out a million years ago, leaving only fossilized skeletons behind. Without the help of DNA, how could we determine that a fossil Labrador, a fossil retriever and a modern Chihuahua all belong to the same species,
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A new study by Florida Museum of Natural History researcher Natasha Vitek shows how scientists can use animals' physical features -- also known as morphology -- to make connections between a modern species and its fossilized relatives, even if they look strikingly different."We can't magically create more fossils," said Vitek, a doctoral candidate in vertebrate paleontology. "A lot of it is trying to figure out what we can do with what we have at hand to find diversity within a species -- diversity we no longer have."Scientists often use color, sexual differences, soft tissues, signs of age and DNA to analyze variation within modern species. But these can be missing in fossil specimens.Vitek relied on a technique known as geometric morphometrics, a way of quantifying an object's shape, to test whether shape is a reliable way to tease out the subtle relationships between species, subspecies and individuals of the same species that just look different from each other.She used eastern box turtles, Unfortunately, turtles don't make anything easy.Modern eastern box turtles display a dizzying amount of variation. A box turtle in Oklahoma can be straw-colored while the same species in Florida is dark with yellow sunburst patterns. Adult box turtles also come in a wide array of sizes with no direct link between size and age. A small turtle in one location could be the same size or older than a large turtle of the same species in another location, even within a short distance.Similar levels of variation also crop up in fossil eastern box turtles. How different must two turtles be to indicate that they belong to different species or subspecies?To make sure she was "comparing apples to apples," Vitek only analyzed the shape of eastern box turtle shells, which preserve well and are common in the fossil record.In doing so, she was wading into a debate about eastern box turtle variation that has lasted more than 80 years, with some scientists suggesting that fossil and modern box turtles are all the same species, while others -- pointing to a distinction in size or shape -- hypothesizing that some fossils represented a separate, extinct species. Some researchers have also argued that certain subtle differences between fossils are evidence of various subspecies.Vitek, who began the study as a master's student at the University of Texas at Austin, compared 435 shells of modern eastern box turtles and 57 shells of fossil specimens, analyzing changes in location, shape, size and sex."It's almost 'more money, more problems,'" Vitek said. "You'd think that with so many fossils, it would be great, but it just means that you can't hide from all the natural complexity."To find a signal in the noise, she used geometric morphometrics to plot shell shape into a series of coordinates, "like a connect-the-dots puzzle," she said, which created a more complete model of a shape in space."This allows you to see how that overall constellation of points is changing from shape to shape," Vitek said. "You might see whole new patterns you would never have thought to measure before and capture things like curvature -- things that are really hard to measure in just a single linear feature."Her results showed that scientists on both sides of the debate are partially right.The argument that modern variation in eastern box turtles mirrors variation in fossil specimens of the same species does have some merit."It's not like we hit the fossil record and there's a hard boundary between what's extinct and what still exists today," she said. "Just like we'd expect from evolution, there is a gradient of variation that carries through to modern box turtles. Having some shells that aren't that different is reassuring in the sense that, yes, some species do go back in time."But, she added, some shells likely do belong to lost subspecies, existing subspecies or closely related extinct species."Some sites have shells that are not only bigger than modern eastern box turtles but also very different," she said. "There is lost variation in the eastern box turtle record. It turns out that if you go back to fossils, there is even more diversity than you would be able to pick up just by studying today's box turtles."Vitek said she is hopeful her study will spur more researchers to look deeper at bony structures within species as a means of detecting variation in fossils."We're doing a great job of seeing what drives patterns like mouse coat color, but let's also see what drives patterns in things like mouse teeth and arm bones," she said. "There's a lot of opportunity to start better documenting what the morphology we pick up in the fossil record might actually mean in terms of evolution."
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Endangered Animals
| 2,018 |
March 28, 2018
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https://www.sciencedaily.com/releases/2018/03/180328083421.htm
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Sea turtles use flippers to manipulate food
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Sea turtles use their flippers to handle prey despite the limbs being evolutionarily designed for locomotion, a discovery by Monterey Bay Aquarium researchers published today in
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The in-depth examination of the phenomenon -- Limb-use By Foraging Sea Turtles, an Evolutionary Perspective -- by authors Jessica Fujii and Dr. Kyle Van Houtan and others reveals a behavior thought to be less likely in marine tetrapods is actually widespread and that this type of exaptation of flippers may have been occurring 70 million years earlier than previously thought."Sea turtles don't have a developed frontal cortex, independent articulating digits or any social learning," says Van Houtan, Director of Science at Monterey Bay Aquarium. "And yet here we have them 'licking their fingers' just like a kid who does have all those tools. It shows an important aspect of evolution -- that opportunities can shape adaptations."Lead author Jessica Fujii is part of the Aquarium's sea otter research team where she specializes in ecomorphology -- the intersection of evolution, behavior and body form. Fujii's expertise in sea otter foraging and tool use behavior has influenced her recent examination of sea turtles and how they have evolved to use their limbs in novel ways.Analysis by Fujii and Van Houtan using crowd-sourced photos and videos finds widespread examples of behaviors such as a green turtle holding a jelly, a loggerhead rolling a scallop on the seafloor and a hawksbill pushing against a reef for leverage to rip an anemone loose.Similar behaviors have been documented in marine mammals from walruses to seals to manatees -- but not in sea turtles. The paper shows that sea turtles are similar to the other groups in that flippers are used for a variety of foraging tasks (holding, bracing, corralling)."Sea turtles' limbs have evolved mostly for locomotion, not for manipulating prey," Fujii says. "But that they're doing it anyway suggests that, even if it's not the most efficient or effective way, it's better than not using them at all."The finding came as a surprise to the authors, given sea turtles' ancient lineage and the fact that the reptiles are considered to have simple brains and simple flippers. The results also offer an insight into the evolution of four-limbed ocean creatures that raises questions about which traits are learned and which are hardwired."We expect these things to happen with a highly intelligent, adaptive social animal," Van Houtan says. "With sea turtles, it's different; they never meet their parents," Kyle says. "They're never trained to forage by their mom. It's amazing that they're figuring out how to do this without any apprenticing, and with flippers that aren't well adapted for these tasks."The study may also help inform the aquarium's ongoing sea otter research. How developmental biology predisposes animals to adopt dining strategies is of particular interest, given the aquarium's efforts to raise stranded sea otter pups and prepare them for a return to the wild. Rearing and releasing stranded pups contributes to the aquarium's work to recover California's threatened sea otter population.Before they're released, ecologically naïve pups have to be taught foraging behaviors, be it for crabs or abalone, by adult female sea otters at the aquarium, which serve as surrogate mothers to the pups."What we're trying to understand is how to have the best sea otter surrogacy program," Kyle says. "This is kind of one end of the spectrum of that -- the opposite end of the spectrum."
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Endangered Animals
| 2,018 |
March 27, 2018
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https://www.sciencedaily.com/releases/2018/03/180327194353.htm
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Iconic swallowtail butterfly at risk from climate change
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Norfolk's butterflies, bees, bugs, birds, trees and mammals are at major risk from climate change as temperatures rise -- according to new research from the University of East Anglia.
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Researchers carried out the first in-depth audit of its kind for a region in the UK to see how biodiversity might be impacted in Norfolk as the world warms.The study finds that the region's Swallowtail Butterfly, which can't be found anywhere else in the UK, is at risk -- along with three quarters of bumblebee, grasshopper and moth species.Dr Jeff Price analysed local populations of 834 species found throughout Norfolk to show how they might fare as climate change reaches 2oC -- the upper end of the UN's Paris Climate Agreement goals. He also looked at what will happen at 3.2oC -- the current global trajectory if countries meet their international pledges to reduce COThe results, published today in The project reveals that at just 2The new climate potentially becomes unsuitable for 15 species of birds including Lapland Bunting and Pink-footed Goose. Meanwhile the Common Shrew, Roe Deer and European Badger are among seven mammal species which may be lost from Norfolk.The Swallowtail Butterfly, local only to the Norfolk Broads, and Red Admirals are among 11 types of butterfly which could be affected.The Common Frog, Great Crested Newt, Adders, and the Common Lizard could also be lost.As climate change reaches 3.2oC, temperatures would be largely or completely unsuitable for mammals including Grey Squirrels, Whiskered Bats and Reeves' Muntjac and trees including Silver Birch, Horse Chestnut, Scots Pine and Norway Spruce.Additionally, 83 per cent of shield bugs, 84 per cent of moths, 78 per cent of bumblebees, and 45 per cent of butterflies including the Small Tortoiseshell could also be affected.The findings come after UEA research revealed that up to half of all plant and animal species in the world's most naturally rich areas could face local extinction by the turn of the century due to climate change if carbon emissions continue to rise unchecked.Lead researcher Dr Jeff Price, from UEA's Tyndall Centre for Climate Change Research and School of Environmental Sciences, said: "This research shows that climate change really will pose increasing risks to biodiversity both globally and in Norfolk."This is a comprehensive investigation of how climate change will impact Norfolk's biodiversity. I was able to carry out this research thanks to a long tradition of citizen science in the county. The Norfolk and Norwich Naturalist's Society was founded in 1869 and their members provided data used in the study."Robert Marsham (1708-1797) of Stratton Strawless, Norfolk, is considered to be the founding father of the science of phenology through his painstaking studying over 60 years published as Indications of Spring. The effect of changing seasons on plants and animals is now one of the well-documented consequences of climate change."The important thing to remember here is that global warming has already reached 1oC above pre-industrial levels. We're currently on a trajectory for 3.2"Norfolk's offshore wind turbines are an excellent example of the beginning of the transition that is needed worldwide to protect biodiversity here in Norfolk and everywhere else."The Paris Climate Agreement aims to put the world on track to avoid dangerous climate change by limiting global warming to 1.5"But 2oC is a tipping point at which climate conditions will become largely or completely unsuitable for many species."Insects are essential food to many other species. Their decline will have a knock-on effect for the food webs of Norfolk's ecosystems of the Broads and the Coast."The loss of bumblebees potentially has a major impact on pollination of crops and other plants," he added.David North, head of People and Wildlife at Norfolk Wildlife Trust, said: "'The likely impacts of climate change on our wildlife, shown by this detailed research, are hugely worrying."It is unthinkable that, with a warming of 2"Unless we take bold action to limit warming to below this level there will be huge changes to our wildlife -- both common and rare."Not all taxa were examined as part of this study, but future work will look in detail at hoverflies, spiders and flowering plants.'The potential impacts of climate change on the biodiversity of Norfolk Species' is published in
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Endangered Animals
| 2,018 |
March 27, 2018
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https://www.sciencedaily.com/releases/2018/03/180327102633.htm
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Mass extinction with prior warning
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Mass extinctions throughout the history of the Earth have been well documented. Scientists believe that they occurred during a short period of time in geological terms. In a new study, palaeobiologists at Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) and their research partners have now shown that signs that the largest mass extinction event in the Earth's history was approaching became apparent much earlier than previously believed, and point out that the same indicators can be observed today.
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Mass extinctions are rare events that have catastrophic consequences. These events often completely change the course of evolution. For example, the rise of mammals -- and therefore of humans -- would probably not have been possible had dinosaurs not become extinct 65 million years ago. A meteorite hit the Earth plunging it into darkness and causing a huge drop in temperature. The subsequent hunger crisis wiped out more than 70 percent of all animal species. Man's ancestors were among the lucky survivors.The consequences of the extinction of species that occurred around 250 million years ago at the Permian-Triassic boundary were even more catastrophic. Gigantic volcanic eruptions and the greenhouse gas emissions they caused wiped out around 90 percent of all animal species according to estimates. For over twenty years, the dominant opinion in research was that this 'mother of all disasters' happened abruptly and without warning, when seen on a geological time-scale -- estimates suggest a period of just 60,000 years.In a new study published in the March edition of the The warning signs of mass extinction are also visible today.The factors that led to a mass extinction at the end of the Permian Period remind us very much of today, says Prof. Wolfgang Kießling. 'There is much evidence of severe global warming, ocean acidification and a lack of oxygen. What separates us from the events of the past is the extent of these phenomena. For example, today's increase in temperature is significantly lower than 250 million years ago'.However, the warning signs that Wolfgang Kießling's team found towards the end of the Permian Period can already be seen today. 'The increased rate of extinction in all habitats we are currently observing is attributable to the direct influence of humans, such as destruction of habitat, over-fishing and pollution. However, the dwarfing of animal species in the oceans in particular can be quite clearly attributed to climate change. We should take these signs very seriously.'The work was carried out by the TERSANE research unit, which is based at FAU (FOR 2332). In this interdisciplinary project, eight working groups investigated under which conditions natural greenhouse gas emissions can reach catastrophic levels and how they are connected to crises in biodiversity.
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Endangered Animals
| 2,018 |
March 27, 2018
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https://www.sciencedaily.com/releases/2018/03/180327093922.htm
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Salvage logging is often a pretext for harvesting wood
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Bia?owie?a Forest in Eastern Poland is one of the last remaining primeval forests in Europe. For the time being. In 2017, the Polish government had 100,000 more trees logged than previously, despite the fact that large areas of the Natural World Heritage site are under strict protection. They did this under the pretense of preventing the bark beetle from spreading further. The motor saws are quiet now after protests from environmental activists, Europe-wide criticism in the media and concerns by the European Commission. The case has been handed to the European Court and the minister of the environment was sacked.
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But this case is not an exception. Professor Jörg Müller wonders why politics and the media have singled out Poland as the culprit: "Unfortunately, such salvage logging activities in protected forests are on the rise worldwide." Together with colleagues from the University of Würzburg he wrote a policy perspective recently published in the journal For their study, the members of the Würzburg Biocenter collated 42 case studies from 26 countries and interviewed local experts about the reasons and responsibilities of salvage logging. "Contrary to what is often communicated to the public, the main motivation for logging in protected areas is economic profit -- pest control comes only second," Müller explains. The forest ecologist is in charge of the Field Station "Fabrikschleichach" of the University of Würzburg. Situated in the heart of the Steigerwald forest, the station's focus is on forest ecology, natural preservation biology and applied biodiversity research.Salvage logging makes sense in areas where wood production is the priority in order to harvest wood while it is still usable. It is, however, not necessary for the forest's biodiversity and regeneration capacity. Especially disturbances such as storms and bark beetle infestation create valuable forest habitats for many endangered species. "They are drivers of increased species variety and structural diversity," Müller says.According to Müller, salvage logging is often simply a pretext for harvesting wood. He says: "They deliberately capitalize on the lack of knowledge in the population regarding natural disturbances." While many people advocate the conservation of green, mature forests, chaotic forest landscapes are considered as in need of sanitation. As a result, society even accepts the use of large machinery in protected areas in many places.A lot of endangered forest species would find vital refuge in such areas. "We were surprised at how regularly these areas are cleared in conservation areas," Müller says. Also, the researchers were astonished to find that the IUCN (International Union for Conservation of Nature) and the FSC (Forest Stewardship Council) don't seem to appreciate this problem either. "There are no guidelines for protected area management by the IUCN, nor is the subject of 'reasonable management of naturally disturbed areas' part of the FSC certification process. As a result, local forest managers, who frequently oppose economic interests in wood, often find themselves isolated," Müller explains.Müller and his colleagues have developed concrete recommendations based on their paper to promote new policies for managing post-disturbance areas. Firstly, the practice of salvage cutting should be banned completely from protected areas, unless there is a risk of personal injury or loss of property. "It would surely make sense for the IUCN to revise its guidelines in this respect," Müller says and he adds: "There are many national parks in Germany that include forests where disturbances are very likely to occur over the next years. It is crucial to develop an enhanced protected area management based on our present ecological knowledge."Another recommendation of the Würzburg ecologists is also a field of work which they will continue to push on: "We need more integrated studies on the economic and ecological impacts of salvage logging and its acceptance in society," says Simon Thorn, who also works at the field station. Moreover, these evaluations should improve forest management planning. In future, disturbance areas need to be explicitly included in the planning process, before disturbances actually occur. This is, however, a complex task to implement and requires government funding.Besides concrete actions in forests, politics and the industry, the Würzburg researchers point out another important angle: the knowledge about forests as an ecosystem. "Pupils as well as students of forestry, biology and environmental protection programmes should already learn about the positive effects of disturbance areas and the negative impacts of excessive salvage cutting in forest ecosystems," Müller says and he adds: "Maybe humans need to learn to trust nature again. We also see this in our biology students in Würzburg."
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Endangered Animals
| 2,018 |
March 26, 2018
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https://www.sciencedaily.com/releases/2018/03/180326152346.htm
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What three feet of seawater could mean for the world's turtles
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Ninety percent of the world's coastal freshwater turtle species are expected to be affected by sea level rise by 2100, according to a study from the University of California, Davis.
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The study, published in Early View online today in the journal "About 30 percent of coastal freshwater species have been found or reported in a slightly saltwater environment," said lead author Mickey Agha, a UC Davis graduate student in associate professor Brian Todd's lab in the Department of Wildlife, Fish and Conservation Biology. "But they tend to live within a low-level range of salinity. If sea level rise increases salinity, we don't yet know if they'll be able to adapt or shift their range."Of the world's 356 turtle species, only about seven are sea turtles, 60 are terrestrial tortoises, and the rest live in freshwater environments, such as lakes, ponds and streams. Of those, about 70 percent live near coastlines, which are expected to experience rising sea levels. Some freshwater turtles lose body mass and can die when exposed to high levels of salty water, while others can tolerate a broader range of salinity.UC Davis wildlife biologists have been studying western pond turtles in the semi-salty waters of Suisun Marsh in Northern California. While abundant in the marsh, this species is in decline in many other parts of the state. The researchers observed that the turtles could face a triple threat of drought, water diversions and increased sea level rise, all of which can result in saltier habitats for them. It prompted the researchers to wonder not only how the western pond turtle would cope with such changes, but also how freshwater turtles around the world are expected to fare under the projected sea level rise of three feet by 2100.In their assessment, the study's authors used a warming scenario projected for 2100 to overlay estimates of sea level rise on georeferenced maps of coastal turtle species worldwide.The results indicated that turtles most at risk from sea level rise live in Oceania -- Southeast Asia, Australia, and New Guinea -- and southeastern North America. In those regions, about 15 species may lose more than 10 percent of their present range.Of the species most affected, half live on the island of New Guinea, where many species are predicted to see an average of 21 percent of their range flooded by a 3-foot rise in sea level.Additionally, the study estimates that sea level rise will affect:Turtles are arguably one of the more beloved reptiles on the planet."They're harmless, they're friendly, they live a long time," said senior author Todd. "They're about as inoffensive as you can get for an animal, and they've existed for so long."Western pond turtles, for example, can survive more than 50 years in the wild. And turtle species have been on Earth for tens of millions of years.More research is needed to see how freshwater turtles can adapt and adjust to these changing environments, but what researchers see now raises concerns."If we've underestimated the impact of sea level rise along coastlines, we don't yet know whether these turtles can adapt or shift fast enough to move with the changing salinity, or whether that part of its range will be gone forever," Agha said.Todd added: "This is a species that is slow to evolve. If we rely on natural selection to sustain them, they will likely disappear."Additional co-authors include Joshua Ennen and Sarah Sweat from the Tennessee Aquarium Conservation Institute, Deborah Bower of James Cook University in Australia, and A. Justin Nowakowski from UC Davis.The research was supported in part by the California Department of Water Resources, the UC Davis office of Graduate Studies, and the Tennessee Aquarium Conservation Institute.
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Endangered Animals
| 2,018 |
March 26, 2018
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https://www.sciencedaily.com/releases/2018/03/180326140204.htm
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Vulnerability and extinction risk of migratory species from different regions and ecosystems worldwide
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Forty million miles of major roads crisscross the Earth's continents -- enough to circle the planet 1,600 times. For humans, these thoroughfares are a boon, enabling them to move with ease from place to place. But for migrating animals who are also hemmed in by dams, rivers, shipping lanes, urban development and agriculture, they create another barrier.
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As human development and activities continue to expand, scientists have grown increasingly concerned about such migrators, especially those that trek long distances. These animal travelers cover hundreds to thousands of kilometers annually, yet very little is known about how their movements are faring across the globe.To expand the scientific knowledge base, a team of UC Santa Barbara scientists set out to estimate the vulnerability and extinction risk of migratory birds, mammals and fishes from different regions and ecosystems around the world. They did so using the existing literature and information from two large databases: the Living Planet Index and the International Union for Conservation of Nature (IUCN) Red List. The group's analysis now appears in a special edition of "As expected, we found that the vulnerability of migratory animals varied depending on the regional, environmental, behavioral and taxonomic context of the species," explained lead author Molly Hardesty-Moore, a graduate student in UCSB's Department of Ecology, Evolution, and Marine Biology. "Our results offer both an opportunity and a roadmap for mounting strategic interventions if we want to preserve this ecologically and economically important phenomenon."The researchers examined more than 6,000 migratory species by taxonomic group (birds, mammals and fishes) and by environmental system (terrestrial, marine or freshwater). They also determined whether a group's movement exhibited collective behavior -- think schools of fish, flocks of geese flying in formation, even herds of wildebeests, all of whom sense cues from their individual members to help guide their collective movement.The team's analysis revealed that while migratory birds are relatively abundant, their numbers are decreasing disproportionately to nonmigratory birds. Take the Arctic tern, the longest-distance migrator, which annually travels 50,000 miles. It is listed as "least concern" by the IUCN because of its large range and abundance of individuals, yet its overall population has been declining for a number of decades. According to Hardesty-Moore, this presents an opportunity for conservation through the implementation of preventive efforts to slow population decline before the species nears extinction.The converse was found to be true for migratory mammals, whose population size is increasing compared to their nonmigratory counterparts. Nonetheless, IUCN lists them as "more endangered.""The relative increase of migratory mammals compared to nonmigratory mammals underscores the success of previous conservation efforts," Hardesty-Moore said. "Still, migratory mammals have an overall high extinction risk because they face so many barriers -- roads and development, hunting and poaching -- so more work still needs to be done."For example, until recently, the Tibetan antelope was "endangered," but it has rebounded because of rigorous conservation efforts. While their numbers remain fairly low and their ranges are restricted, conservation efforts have been able to increase their populations. "I think that's good news," Hardesty-Moore said. "It shines some light on conservation successes."The scientists also found that migratory freshwater fishes are at greater risk than their marine brethren, which makes sense considering that the avenues of travel available to freshwater species are much more restricted. Dams are a major problem for some of these migrators -- there are at least 37,600 hydropower dams in rivers globally, with hundreds more in progress. For example, more than 400 dams limit the migration capability of Chinook salmon in the Columbia River basin. As a result, the species is "highly endangered." Marine migrants, on the other hand, are better able to maneuver around barriers or to skirt fishing pressures."Our research showed that conservation efforts for migratory species work in certain circumstances, but we also identified regions and groups of animals in trouble," Hardesty-Moore explained. "We were able to pinpoint some of those and highlight areas of interest to conservation biologists. If we want to preserve this fascinating, ecologically meaningful part of life, we will need to find a way to coexist with these species, especially because of increasing human development around the globe."
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Endangered Animals
| 2,018 |
March 26, 2018
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https://www.sciencedaily.com/releases/2018/03/180326110046.htm
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Chance is a factor in the survival of species
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In a major study, biologists at Lund University in Sweden have studied the role of chance in whether a species survives or dies out locally. One possible consequence according to the researchers, is that although conservation initiatives can save endangered species, sometimes chance can override such efforts.
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Species that differ considerably in their ecology rarely have problems living in close proximity as they do no compete for the same natural resources. When, however, two similar species live side by side and utilize the same food, habitat and other resources, this often leads to one of the species outcompeting the other, according to traditional ecological theory.The role of chance as a contributing mechanism whether species dies out locally is not near as well investigated as is competition, and limited empirical data is available. The recent study is one of the most extensive to date, and is based on experiments and computer simulations combined with field studies.The results show that chance has a certain significance, and that it is not possible in advance to say which of two co-existing species will die out locally.The researchers have also studied a factor that counteracts the role of chance, known as negative frequency-dependence. . The mechanism can be described as an elastic band that is stretched out, but pulls back when a species becomes rare. This is because the few remaining individuals in the rare species gain some minority advantages, such as reduced competition or aggression from other individuals. The effect is that the rare species becomes more common again."Sometimes the elastic band doesn't work or pulls back too late. Then the species dies out locally," explains Erik Svensson, biologist at Lund University.Conservation initiatives can sometimes help to save species and thereby maintain local biodiversity."Such efforts are definitely not futile. But the world is never totally predictable and our study shows that chance plays some role for whether a species survives locally or not. Perhaps we humans have less power than we think," he concludes.
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Endangered Animals
| 2,018 |
March 23, 2018
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https://www.sciencedaily.com/releases/2018/03/180323104803.htm
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Monitor climate change, not predators, to protect lake diversity
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Climate change and other environmental factors are more threatening to fish diversity than predators, according to new research from the University of Guelph.
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It is a surprising and important finding, as humans rely upon freshwater lakes for more than one-fifth of their protein needs worldwide, says lead author Prof. Andrew MacDougall in U of G's Department of Integrative Biology."Freshwater is a huge source of food for people, including Ontario's Great Lakes," he said.Lakes, rivers and streams cover less than one per cent of Earth's surface but provide 12 per cent of human fish consumption, MacDougall said.The findings, published this month in the journal His international research team included U of G biologist Prof. Kevin McCann and scientists in Canada, Switzerland, Sweden, Australia, the United States and Japan.The research team modelled prey-predator interactions and environmental factors, such as lake size, temperature and water quality.The scientists used information compiled earlier by the Ontario government on more than 700 lakes in the Great Lakes watershed.The team found that species diversity depends more on "bottom-up" environmental factors than on "top-down" interactions, or which fish species eats what -- a result that surprised MacDougall.He said food chain interactions among organisms are still important."All lakes have big predators, and predators always kill lots of fish that they consume," said MacDougall. "But the strength and degree of the interactions seems to depend fully on environment. The interactions are never independent of lake conditions."He said resource managers need to pay attention to physical conditions, including lake warming caused by climate change and water quality impacts of human activities such as farming.The authors say the paper's findings set a baseline for species diversity in southern Ontario lakes. That will help resource managers monitor or predict those effects as well as the impacts of other changes such as introduction of invasive species.Many freshwater fish species in Canada and abroad are already endangered by human-caused environmental changes, said McCann. "There's a looming threat of loss of species."He said the study shows how so-called big data can help detect patterns in complicated ecosystems and how precision agriculture -- including more targeted use of crop fertilizers -- may lessen pollutants entering lakes and streams.Big data and precision agriculture are key aspects of the University's Food from Thought project, which aims to help find sustainable ways to feed Earth's growing human population. McCann co-leads that project, launched in 2016.U of G researchers in the new study were supported by funding from the Natural Sciences and Engineering Research Council and from the Canada First Excellence Research Fund for the Food from Thought project.
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Endangered Animals
| 2,018 |
April 22, 2021
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https://www.sciencedaily.com/releases/2021/04/210422093847.htm
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Common antibiotic effective in healing coral disease lesions
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Diseases continue to be a major threat to coral reef health. For example, a relatively recent outbreak termed stony coral tissue loss disease is an apparently infectious waterborne disease known to affect at least 20 stony coral species. First discovered in 2014 in Miami-Dade County, the disease has since spread throughout the majority of the Florida's Coral Reef and into multiple countries and territories in the Caribbean. Some reefs of the northern section of Florida's Coral Reef are experiencing as much as a 60 percent loss of living coral tissue area.
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A new study by researchers at Florida Atlantic University's Harbor Branch Oceanographic Institute reveals how a common antibiotic used to treat bacterial infections in humans is showing promise in treating disease-affected Montastraea cavernosa coral colonies in situ. M. cavernosa, also known as the Great Star Coral, is a hard or stony coral found widely throughout the tropical western Atlantic, including several regions currently affected by stony coral tissue loss disease. Preserving M. cavernosa colonies is of particular importance due to its high abundance and role as a dominant reef builder in the northern section of Florida's Coral Reef.The objective of the study, published in "There are three possible scenarios that may explain the appearance of new lesions in the amoxicillin treated lesions of the corals that had healed in our study," said Erin N. Shilling, M.S., first author and a recent graduate of the Marine Science and Oceanography masters degree program at FAU Harbor Branch. "It's possible that the causative agent of stony coral tissue loss disease is still present in the environment and is re-infecting quiesced colonies. It also could be that the duration and dose of this antibiotic intervention was sufficient to arrest stony coral tissue loss disease at treated lesions, but insufficient at eliminating its pathogens from other areas of the coral colony."The study was conducted approximately 2 kilometers offshore from Lauderdale-by-the-Sea in Broward County, Florida, at sites with a maximum depth of 10 meters. Both colony disease status and treated lesion status were analyzed independently so that the treatment's effectiveness at halting individual lesions could be assessed while also determining if a treatment had any impact on the colony as a whole. Colonies were monitored periodically over 11 months to assess treatment effectiveness by tracking lesion development and overall disease status."Success in treating stony coral tissue loss disease with antibiotics may benefit from using approaches typically successful against bacterial infections in humans, for example using a strong initial dose of antibiotics followed by a regimen of smaller supplementary doses over time," said Joshua Voss, Ph.D., senior author, an associate research professor at FAU Harbor Branch and executive director of the NOAA Cooperative Institute for Ocean Exploration, Research, and Technology. "Future research efforts should focus on assessing the potential unintended consequences of antibiotic treatments on corals, their microbial communities, and neighboring organisms. In addition, further efforts are needed to optimize dosing and delivery methods for antibiotic treatments on stony coral tissue loss disease-affected corals and scale up intervention treatments effectively."Voss notes that many coral diseases are still poorly characterized, which has led to calls for increased research and intervention efforts to support adaptive management strategies particularly given the considerable impacts of diseases on coral reefs over the past five decades."Results of our experiment expand management options during coral disease outbreaks and contribute to overall knowledge regarding coral health and disease," said Voss.This research is part of a highly coordinated collaboration through the Disease Advisory Committee (DAC) organized by the Florida Department of Environmental Protection (Ian Combs, M.S., another recent FAU graduate from Voss's lab and a co-author, helped to develop some of the coral fate-tracking techniques used in the study."We recommend that coral reef managers and intervention specialists, particularly those focusing on stony coral tissue loss disease, adopt 3D photogrammetric methods to ensure that data are more accurate than 2D and in-water estimates," said Combs.
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Extinction
| 2,021 |
March 30, 2021
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https://www.sciencedaily.com/releases/2021/03/210330143112.htm
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Status of greater sage-grouse populations
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Greater sage-grouse populations have declined significantly over the last six decades, with an 80% rangewide decline since 1965 and a nearly 40% decline since 2002, according to a new report by the U.S. Geological Survey. Although the overall trend clearly shows continued population declines over the entire range of the species, rates of change do vary regionally.
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The report represents the most comprehensive analysis of greater sage-grouse population trends ever produced and lays out a monitoring framework to assess those trends moving forward. The study can also be used to evaluate the effectiveness of greater sage-grouse conservation efforts and analyze factors that contribute to habitat loss and population change -- all critical information for resource managers."Every day, the USGS brings diverse stakeholders the compelling science they need to make strategic, on-the-ground policy and management decisions," said David Applegate, associate director exercising the delegated authority of the USGS director. "With this framework in place, resource managers can more nimbly respond to population declines with actions such as redistributing monitoring efforts or prioritizing where management intervention may be needed."USGS scientists and colleagues developed the framework to estimate greater sage-grouse population trends in the 11 western states where the species lives -- California, Colorado, Idaho, Montana, Nevada, North Dakota, Oregon, South Dakota, Utah, Washington and Wyoming. The greater sage-grouse is a vulnerable species and an indicator of the overall health of the iconic sagebrush ecosystem.The research found that in recent decades the rate of greater sage-grouse decline increased in western portions of the species' range, particularly in the Great Basin, while the declines have been less severe in eastern areas. Western Wyoming was the only region to show relatively stable sage-grouse populations recently. Taken as a whole, the greater sage-grouse population now is less than a quarter of what it was more than 50 years ago.To complete the framework, USGS and Colorado State University researchers collaborated with the Western Association of Fish and Wildlife Agencies, individual state wildlife agencies and the Bureau of Land Management. Together, they compiled information and created a rangewide database of greater sage-grouse breeding grounds. Researchers used that information to assess past and current sage-grouse population trends in different parts of the species' range.In addition to the database and population-trend assessment, researchers also developed a "Targeted Annual Warning System" to alert biologists and managers when local greater sage-grouse populations begin to decline or have diverged from regional trends. The research identified the most at-risk breeding grounds, with the greatest risk seen at the periphery of the species' range. The report shows that there is only a 50% chance that most breeding grounds, called leks, will be productive in about 60 years from now if current conditions persist. USGS scientists will continue to analyze information to determine the factors driving changes in breeding areas and populations, including the influence of habitat loss and degradation."The framework we developed will help biologists and managers make timely decisions based on annual monitoring information," said Peter Coates, USGS scientist and lead author of the report. "This will allow them to address local issues before they have significant impacts on the population."
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Extinction
| 2,021 |
March 29, 2021
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https://www.sciencedaily.com/releases/2021/03/210329153346.htm
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Scientists zero in on the role of volcanoes in the demise of dinosaurs
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Earth has experienced five major mass extinction events over the past 500 million years. Massive volcanic eruptions have been identified as the major driver of the environmental changes that precipitated at least three of these extinction events. The fifth and most recent event -- the end-Cretaceous mass extinction -- occurred 66 million years ago and was responsible for wiping out dinosaurs. Researchers have long debated whether gas emissions from volcanic eruptions from the Deccan Traps (an enormous volcanic province located in India) or the impact of a large asteroid is most responsible for causing the climate changes that triggered that event. Now, a multi-institutional research team led by scientists from The Graduate Center, CUNY has analyzed the amount and timing of CO
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Recent research has identified a global warming event that occurred several hundred thousand years before the end-Cretaceous extinction. Some scientists have linked the eruption of the Deccan Traps to this warming event, but there is debate over whether the lavas that erupted could have released enough CO"Our team analyzed Deccan Traps COFor their study, the team -- which included Hernadez Nava and Professor Benjamin Black from The Graduate Center and The City College of New York (CUNY); geochemist Sally Gibson from University of Cambridge; geoscientist Robert Bodnar from Virginia Tech; geologist Paul Renne of University of California, Berkeley; and geochemist Loÿc Vanderkluysen of Drexel University -- used lasers and beams of ions to measure the amount of COThe team's findings help fill a significant knowledge gap about how magmas interacted with climate during this crucial period in Earth's history. Their data show that CO"Our lack of insight into the carbon released by magmas during some of Earth's largest volcanic eruptions has been a critical gap for pinning down the role of volcanic activity in shaping Earth's past climate and extinction events," said Black, the study's principal investigator and a professor in the Earth and Environmental Science program at The Graduate Center CUNY and City College of New York. "This work brings us closer to understanding the role of magmas in fundamentally shaping our planet's climate, and specifically helps us test the contributions of volcanism and the asteroid impact in the end-Cretaceous mass extinction."This research was funded by the National Science Foundation through grant EAR 1615147.
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Extinction
| 2,021 |
February 25, 2021
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https://www.sciencedaily.com/releases/2021/02/210225082530.htm
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Paleontologists discover new insect group after solving 150-year-old mystery
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For more than 150 years, scientists have been incorrectly classifying a group of fossil insects as damselflies, the familiar cousins of dragonflies that flit around wetlands eating mosquitoes. While they are strikingly similar, these fossils have oddly shaped heads, which researchers have always attributed to distortion resulting from the fossilization process.
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Now, however, a team of researchers led by Simon Fraser University (SFU) paleontologist Bruce Archibald has discovered they aren't damselflies at all, but represent a major new insect group closely related to them.The findings, published today in "When we began finding these fossils in British Columbia and Washington State, we also thought at first they must be damselflies," says Archibald.But on closer inspection, the team noticed they resembled a fossil that German paleontologist Hermann Hagen wrote about in 1858. Hagen set the precedent of linking the fossil to the damselfly suborder despite its different head shape, which didn't fit with damselflies at all.Damselflies have short and wide heads with eyes distinctively protruding far to each side. Hagen's fossil, however, had an oddly rounded head and eyes. But he assumed this difference was false, caused by distortion during fossilization."Paleontologists since Hagen had written that these were damselflies with distorted heads," Archibald says. "A few hesitated, but still assigned them to the damselfly suborder."The SFU-led team, including Robert Cannings of the Royal British Columbia Museum, Robert Erickson and Seth Bybee of Brigham Young University and SFU's Rolf Mathewes, sifted through 162 years of scientific papers and discovered that many similar specimens have been found since Hagen's time.They experienced a eureka moment when they realized the odd heads of their new fossils were, in fact, their true shape.The researchers used the fossil's defining head shape to name the new suborder Cephalozygoptera, meaning "head damselfly."The oldest known species of Cephalozygoptera lived among dinosaurs in the Cretaceous age in China, and were last known to exist about 10 million years ago in France and Spain."They were important elements in food webs of wetlands in ancient British Columbia and Washington about 50 million years ago, after the extinction of the dinosaurs," says Archibald. "Why they declined and went extinct remains a mystery."The team named 16 new species of Cephalozygoptera. Some of the fossils were found on the traditional land of the Colville Indian tribe of northern Washington, and so Archibald and his coauthors collaborated with tribal elders to name a new family of them. They called the family "Whetwhetaksidae," from the word "whetwhetaks," meaning dragonfly-like insects in the Colville people's language.Archibald has spent 30 years combing the fossil-rich deposits of southern British Columbia and northern interior Washington. To date, in collaboration with others, he has discovered and named more than 80 new species from the area.
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Extinction
| 2,021 |
February 24, 2021
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https://www.sciencedaily.com/releases/2021/02/210224143501.htm
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Asteroid dust found in crater closes case of dinosaur extinction
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Researchers believe they have closed the case of what killed the dinosaurs, definitively linking their extinction with an asteroid that slammed into Earth 66 million years ago by finding a key piece of evidence: asteroid dust inside the impact crater.
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Death by asteroid rather than by a series of volcanic eruptions or some other global calamity has been the leading hypothesis since the 1980s, when scientists found asteroid dust in the geologic layer that marks the extinction of the dinosaurs. This discovery painted an apocalyptic picture of dust from the vaporized asteroid and rocks from impact circling the planet, blocking out the sun and bringing about mass death through a dark, sustained global winter -- all before drifting back to Earth to form the layer enriched in asteroid material that's visible today.In the 1990s, the connection was strengthened with the discovery of a 125-mile-wide Chicxulub impact crater beneath the Gulf of Mexico that is the same age as the rock layer. The new study seals the deal, researchers said, by finding asteroid dust with a matching chemical fingerprint within that crater at the precise geological location that marks the time of the extinction."The circle is now finally complete," said Steven Goderis, a geochemistry professor at the Vrije Universiteit Brussel, who led the study published in The study is the latest to come from a 2016 International Ocean Discovery Program mission co-led by The University of Texas at Austin that collected nearly 3,000 feet of rock core from the crater buried under the seafloor. Research from this mission has helped fill in gaps about the impact, the aftermath and the recovery of life.The telltale sign of asteroid dust is the element iridium -- which is rare in the Earth's crust, but present at elevated levels in certain types of asteroids. An iridium spike in the geologic layer found all over the world is how the asteroid hypothesis was born. In the new study, researchers found a similar spike in a section of rock pulled from the crater. In the crater, the sediment layer deposited in the days to years after the strike is so thick that scientists were able to precisely date the dust to a mere two decades after impact."We are now at the level of coincidence that geologically doesn't happen without causation," said co-author Sean Gulick, a research professor at the UT Jackson School of Geosciences who co-led the 2016 expedition with Joanna Morgan of Imperial College London. "It puts to bed any doubts that the iridium anomaly [in the geologic layer] is not related to the Chicxulub crater."The dust is all that remains of the 7-mile-wide asteroid that slammed into the planet millions of years ago, triggering the extinction of 75% of life on Earth, including all nonavian dinosaurs.Researchers estimate that the dust kicked up by the impact circulated in the atmosphere for no more than a couple of decades -- which, Gulick points out, helps time how long extinction took."If you're actually going to put a clock on extinction 66 million years ago, you could easily make an argument that it all happened within a couple of decades, which is basically how long it takes for everything to starve to death," he said.The highest concentrations of iridium were found within a 5-centimeter section of the rock core retrieved from the top of the crater's peak ring -- a high-elevation point in the crater that formed when rocks rebounded then collapsed from the force of impact.The iridium analysis was carried out by labs in Austria, Belgium, Japan and the United States."We combined the results from four independent laboratories around the world to make sure we got this right," said Goderis.In addition to iridium, the crater section showed elevated levels of other elements associated with asteroid material. The concentration and composition of these "asteroid elements" resembled measurements taken from the geologic layer at 52 sites around the world.The core section and geologic layer also have earthbound elements in common, including sulfurous compounds. A 2019 study found that sulfur-bearing rocks are missing from much of the rest of the core despite being present in large volumes in the surrounding limestone. This indicates that the impact blew the original sulfur into the atmosphere, where it may have made a bad situation worse by exacerbating global cooling and seeding acid rain.Gulick and colleagues at the University of Texas Institute for Geophysics and Bureau of Economic Geology -- both units of the UT Jackson School -- plan to return to the crater this summer to begin surveying sites at its center, where they hope to plan a future drilling effort to recover more asteroid material.
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Extinction
| 2,021 |
February 22, 2021
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https://www.sciencedaily.com/releases/2021/02/210222095022.htm
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Plant responses to climate are lagged
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Plant responses to climate drivers such as temperature and precipitation may become visible only years after the actual climate event. New results indicate that climate drivers may have different effects on the survivorship, growth and reproduction of plant species than suggested by earlier studies.
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Two in five of the world's plant species are at risk of extinction. In the face of climate change, understanding why certain plant species are vulnerable to extinction while others prevail is more urgent than ever before. Previous studies linking climate and plant vital rates have found relatively modest effects, sometimes leading to the conclusion that other threats, such as land use change, may still be more important than climate drivers. However, these conclusions could result from wrong assumptions about which times of the year (which "time window") climate drivers such as temperature and precipitation influence plant species. "Most researchers assume that plant populations respond to the climate within twelve months and only use this time window in their models to analyse plant responses," says first author Sanne Evers from iDiv and MLU.For their study, the team of researchers led by iDiv, MLU and UFZ analysed 76 studies performed on 104 plant species that link climate drivers with demographic responses. They found that 85% of all studies considered 1-year time windows, and often focus on the growing season (e.g. spring and/or summer). However: "There are many ways in which climate during the dormant season, or climate that occurred few years in the past, can influence the survivorship, growth, and reproduction of plants. For example, species can grow substantially during the cold season, at least where the cold season temperature does not fall below 5° Celsius. In addition, it might take multiple years for plants to die after physiological damage from drought has occurred," says Aldo Compagnoni from iDiv and MLU and senior author of the paper.To investigate which combination of climate drivers and temporal window have the best predictive ability, the researchers used four exceptionally long-term data sets: the montane plants Helianthella quinquenervis and Frasera speciosa and the arid plants Cylindropuntia imbricata, and Cryptantha flava. "For these plant species, 15 to 47 years of data was available. And even though they are all perennials, they come from very different habitats with clearly marked seasons," Sanne Evers explains.The results were clear: In many cases, it can take several years for plants to respond to climate. "Plant responses to climate drivers that are lagged and/or outside of the growing season are the rule rather than the exception," says co-author Tiffany Knight, professor at MLU and UFZ and head of a research group at iDiv. "This could be explained by the physiological features of some plants: For instance, in alpine environments, it may take up to four years until leaves and flowers of plants such as F. speciosa reach maturity." Accordingly, the effects of an extreme climate event may only become visible in the number of leaves and flowers four years after that event influenced the formation of these structures.While this study focuses on examining the effects of past climate on plants, there are important implications for understanding how plants will be affected by future climate change. This study highlights that plant responses to climate are more complex than was previously appreciated. We need to prioritize experiments and observations of terrestrial ecosystems in order to create robust scenarios for the plant species that are critical to human well-being.
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Extinction
| 2,021 |
February 16, 2021
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https://www.sciencedaily.com/releases/2021/02/210216115110.htm
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Enormous ancient fish discovered by accident
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Fossilised remains of a fish that grew as big as a great white shark and the largest of its type ever found have been discovered by accident.
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The new discovery by scientists from the University of Portsmouth is a species of the so-called 'living fossil' coelacanths which still swim in the seas, surviving the extinction that killed off the dinosaurs.The discovery was purely serendipitous. Professor David Martill, a palaeontologist from the University's School of the Environment, Geography and Geosciences, had been asked to identify a large bone in a private collection in London.The collector had bought the specimen thinking the bone might have been part of a pterodactyls' skull. Professor Martill was surprised to find it was not in fact a single bone, but composed of many thin bony plates.He said: "The thin bony plates were arranged like a barrel, but with the staves going round instead of from top to bottom. Only one animal has such a structure and that is the coelacanth -- we'd found a bony lung of this remarkable and bizarre looking fish."The collector was mightily disappointed he didn't have a pterosaur skull, but my colleagues and I were thrilled as no coelacanth has ever been found in the phosphate deposits of Morocco, and this example was absolutely massive!"Professor Martill teamed up with leading Brazilian palaeontologist Dr Paulo Brito, of the State University of Rio de Janeiro, to identify the fossil. Dr Brito has studied coelacanths for more than 20 years and is an expert on their lungs, and was astonished at the size of this new specimen.The fossil had been embedded in a block of phosphate, backed with plaster and covered in a coating of lacquer, which had caused the bones to turn brown. It was found next to a pterodactyl which proves it lived in the Cretaceous era -- 66 million years ago.The private owner offered to cut the remains of the bony lung off the slab and give it to the team for free. They then had to remove the coating and further expose the bones using specialist equipment, including dental tools and fine brushes.Professor Martill and colleagues were able to determine they'd found a surprisingly large coelacanth because of the abnormal size of the lung. They calculated it may have been five metres in length -- substantially larger than the rare and threatened modern-day coelacanths, which only grow to a maximum length of two metres.He said: "We only had a single, albeit massive lung so our conclusions required some quite complex calculations. It was astonishing to deduce that this particular fish was enormous -- quite a bit longer than the length of a stand-up paddleboard and likely the largest coelacanth ever discovered."Coelacanth fishes first appeared (evolved) 400 million years ago -- 200 million years before the first dinosaurs. It had long been believed to be extinct, but in 1938 a living coelacanth was found off South Africa.The fossil is now being returned to Morocco where it will be added to the collections in the Department of Geology at Hassan II University of Casablanca.The research is published in
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Extinction
| 2,021 |
February 9, 2021
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https://www.sciencedaily.com/releases/2021/02/210209113837.htm
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COVID-19 vs. conservation: How the northern white rhino rescue programme overcame challenges
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The COVID-19 pandemic -- caused by the novel coronavirus SARS-CoV-2 -- has changed the life of people everywhere and affected economic, cultural, social and political processes. Research and conservation are not exempt from these negative effects, whereas positive consequences of an "anthropause" on the environment are controversially discussed.
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The BioRescue research project, a programme aiming at saving the northern white rhinoceros from extinction, exemplifies the challenges to overcome when conducting research and conservation in an international consortium in times of a global pandemic. COVID-19 hampered communication and travels, prevented or delayed crucial procedures, caused losses in revenues and by that may have lowered the chances of a survival of the northern white rhino. The consortium adjusted strategies, gained valuable knowledge during these challenging times and continued with its mission. The effects of the pandemic on the BioRescue project are described in detail in a scientific paper published in the There are only two northern white rhino individuals left in the world, both females. To prevent the extinction of the northern white rhino, an international consortium of scientists and conservationists seeks to advance assisted reproduction technologies and stem-cell associated techniques to create northern white rhino embryos in-vitro. In the near future, the embryos will be transferred to southern white rhino surrogate mothers to create northern white rhino offspring. This boundary-pushing programme is conducted by an international team working within a global framework and includes scientists and conservationists from institutions in Germany, Kenya, Japan, Czech Republic, USA and Italy. From March 2020 onwards, the work of the consortium has been severely affected by the Covid-19 pandemic in several ways at the local, national and international level.At the international level, the most striking obstacle were international travel restrictions. "The consortium partners had previously agreed upon collecting oocytes from the last two northern white rhinos every three to four months. This is considered a safe interval to maintain the health of the females while maximising the number of harvested oocytes, equivalent to potential future embryos and offspring" says BioRescue project head Thomas Hildebrandt from the Leibniz-Institute for Zoo and Wildlife Research (Leibniz-IZW). Following such an interval, oocyte collection was planned for March 2020 at the Ol Pejeta Conservancy in Kenya. "Owing to international travel restrictions, the procedure had to be cancelled and could only be conducted after the re-opening of Kenya's borders in August 2020," adds Leibniz-IZW BioRescue scientist Susanne Holtze, who shares first authorship of the publication with Hildebrandt. "This does not only mean that one crucial opportunity was missed and possibly several valuable embryos could not be generated, it also affected the subsequent procedure in August 2020," Holtze explains. It is likely that the prolonged interval since the last oocyte collection in December 2019 compromised oocyte quality and was the reason that out of 10 oocytes, no embryos could be created. The delay of possible embryo transfers in Kenya will also decrease chances for northern white rhino calves to grow up with individuals of their kind. This ultimately implies that almost a year was lost for the programme -- a serious delay in the race against time to prevent the extinction of the northern white rhino. "On the other hand, the involuntary break provided us with valuable new insights into the reproduction management of northern white rhinos," says Hildebrandt. "We still made progress in 2020 as we could successfully continue our research with our Kenya mission in December."In addition to the delays in conducting the procedures at Ol Pejeta Conservancy in Kenya, for which strict travel regulations and on-site hygiene rules had to be followed, the pandemic posed several further challenges to the consortium. Lockdown and temporal closures of public facilities caused notable losses in revenues for the consortium partner Safari Park Dvůr Králové in the Czech Republic. "We faced the unprecedented situation of having no revenues from entrance fees and other services. However, against all odds, we were quickly able to develop new ways of how to approach our potential visitors and supporters online and this allowed us to keep our support to the northern white rescue programme on the same level as in previous years. Our highest priority is protecting species from extinction and COVID-19 confirmed how important the support by individual donors is," says Jan Stejskal, the Safari Park's Director of Communication and International Projects. Similarly, the not-for-profit Ol Pejeta Conservancy experienced drastic reductions in revenue from international tourism owing to a ban on international travel, national curfews and the isolation of the capital Nairobi. "Therefore, fundraising was necessary to maintain our wildlife and conservation programmes and pay for salaries," says Ol Pejeta Managing Director, Richard Vigne. "Nevertheless, safeguarding the animals and professional veterinary care were maintained at all times in cooperation with the Kenya Wildlife Service."For the research facilities of the consortium partners in Germany, Italy and Japan, different levels of restrictions were put in place on laboratory work. Crucial work at Leibniz-IZW, Avantea Laboratory of Reproductive Technologies (Italy), Kyushu University (Japan) and the Max Delbrück Center for Molecular Medicine (Germany) could be carried on to a limited extent. "Staff at labs was limited, hygiene rules were enacted, transportation of samples and equipment were hampered and last but not least closure of schools and child care facilities forced parents to switch from lab work to mobile work at home," Sebastian Diecke from Max Delbrück Center sums up. Laboratories and offices at the University of Padova were also closed and online-teaching and research was implemented. The team in charge of the ethical monitoring of the BioRescue programme continued working from home, and had to adjust strategies to carry on the ethical assessment for all procedures. "Despite all difficulties, the ethical assessment was always performed and BioRescue procedures have uninterruptedly maintained high standards of quality and respect for the safety and welfare of both researchers and the animals involved," says Barbara de Mori from University of Padua."COVID-19 has disastrous consequences all over the world, but two new embryos that we produced in December 2020 demonstrate that our BioRescue team is committed to overcome all scientific and logistic challenges the northern white rhino rescue might bring. We will be grateful for everyone who decides to support us in our mission," adds Jan Stejskal."Besides the downside effects of the pandemic, there were also a few positive ones. For example, closure of international borders opened up new opportunities for assisted reproduction procedures in Germany which were important for advancing and perfecting methods and techniques. For example, a designated mating partner of a southern white rhino female in a German zoo could not be transferred and therefore, assisted reproduction was a welcome alternative to regular natural mating. Secondly, social distancing regulations helped to establish a new culture of online meetings within the consortium partners on a more regular basis, which proved useful and will continue in future. Lastly, there is a renewed awareness for the destruction of habitat and the loss of biodiversity as key drivers for emerging zoonotic diseases. "BioRescue is not only about saving the northern white rhino. On the long run it also is a much-needed step for the healing of disrupted habitat in Central Africa and therefor for preventing global pandemics in future," says Thomas Hildebrandt. "It is ironic and bitter, that our mission was severely affected by the very thing it ultimately intends to make more unlikely, a pandemic." More information about BioRescue as well as options how to support the project can be found on
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Extinction
| 2,021 |
January 19, 2021
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https://www.sciencedaily.com/releases/2021/01/210119194316.htm
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Protected areas vulnerable to growing emphasis on food security
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Protected areas are critical to mitigating extinction of species; however, they may also be in conflict with efforts to feed the growing human population. A new study shows that 6% of all global terrestrial protected areas are already made up of cropland, a heavily modified habitat that is often not suitable for supporting wildlife. Worse, 22% of this cropland occurs in areas supposedly enjoying the strictest levels of protection, the keystone of global biodiversity protection efforts.
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This finding was published in the protected areas for the first time, the authors synthesized a number of remotely sensed cropland estimates and diverse socio-environmental datasets.The persistence of many native species -- particularly habitat specialists (species that depend on a narrow set of natural systems), rare, and threatened species -- is incompatible with conversion of habitat to cropland, thus compromising the primary conservation goal of these protected areas. Guided by the needs of conservation end users, the researchers used methods that provide an important benchmark and reproducible methods for rapid monitoring of cropland in protected areas."Combining multiple remote sensing approaches with ongoing inventory and survey work will allow us to better understand the impacts of conversion on different taxa," says lead author Varsha Vijay, a conservation scientist who was a postdoctoral fellow at SESYNC while working on the study. "Cropland in biodiversity hotspots warrant particularly careful monitoring. In many of these regions, expanding cropland to meet increasing food demand exposes species to both habitat loss and increased human-wildlife conflict," she adds.Countries with higher population density, lower income inequality, and higher agricultural suitability tend to have more cropland in their protected areas. Even though cropland in protected areas is most dominant in mid-northern latitudes, the tradeoffs between biodiversity and food security may be most acute in the tropics and subtropics. This increased tradeoff is due to higher levels of species richness coinciding with a high proportion of cropland-impacted protected areas."The findings of this study emphasize the need to move beyond area-based conservation targets and develop quantitative measures to improve conservation outcomes in protected areas, especially in areas of high food insecurity and biodiversity" says Lucas Joppa, chief environmental officer of Microsoft, who has published numerous papers on the topic of protected area effectiveness but who was not an author on the study. 2021 is a historic "Year of Impact," when many countries and international agencies are developing new decadal targets for biodiversity conservation and protected areas. As countries aim to meet these goals and the 2030 Sustainable Development Goals, there is an increasing need to understand synergies and tradeoffs between these goals in order to ensure a more sustainable future. Studies such as these offer insights for protected area planning and management, particularly as future protected areas expand into an agriculturally dominated matrix. Though the study reveals many challenges for the future, it also reveals potential scenarios for restoration in mid-northern latitudes and for cooperation between conservation and food programs in regions with both high levels of food insecurity and biodiversity."Despite clear connections between food production and biodiversity, conservation and development planning are still often treated as independent processes," says study co-author Paul Armsworth from the University of Tennessee. "Rapid advances in data availability provide exciting opportunities for bringing the two processes together," adds Vijay.
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Extinction
| 2,021 |
December 18, 2020
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https://www.sciencedaily.com/releases/2020/12/201218084123.htm
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The 'crazy beast' that lived among the dinosaurs
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New research published today in the
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Named The research, carried out over 20 years, demonstrates that Its "bizarre" features include more trunk vertebrae than most other mammals, muscular hind limbs that were placed in a more sprawling position (similar to modern crocodiles) coupled with brawny sprinting front legs that were tucked underneath the body (as seen in most mammals today), front teeth like a rabbit and back teeth completely unlike those of any other known mammal, living or extinct, and a strange gap in the bones at the top of the snout.A team of 14 international researchers led by Dr David Krause (Denver Museum of Nature & Science) and Dr Simone Hoffmann (New York Institute of Technology) published the comprehensive description and analysis of this opossum-sized mammal that lived among dinosaurs and massive crocodiles near the end of the Cretaceous period (145¬-66 million years ago) on Madagascar.The 234-page monographic treatment, consisting of seven separate chapters, is part of the Society of Vertebrate Paleontology (SVP) Memoir Series, a special yearly publication that provides a more in-depth treatment of the most significant vertebrate fossils. Initial announcement of the discovery was made in the journal Nature earlier this year.Now the research team presents the first skeleton for this mysterious group that once roamed much of South America, Africa, Madagascar, the Indian subcontinent, and even Antarctica.The completeness and excellent preservation of the skeleton of "Knowing what we know about the skeletal anatomy of all living and extinct mammals, it is difficult to imagine that a mammal like Although the life-like reconstruction of As Hoffmann puts it, "While its muscular hind legs and big claws on the back feet may indicate that The limbs of This is not were the strangeness stops.The teeth of Not only did About the size of a Virginia opossum, the 3.1 kg The geological history of Gondwana provides clues as to why "More than anything, the discovery of
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Extinction
| 2,020 |
December 16, 2020
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https://www.sciencedaily.com/releases/2020/12/201216113240.htm
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When dinosaurs disappeared, forests thrived
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It's known that the primary cause of the mass extinction of dinosaurs, about 66 million years ago, was a large asteroid impact. But the exact mechanisms that linked the impact to mass extinction remain unclear, though climactic changes are thought to have played a part.
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To understand how the mass extinction and associated climate changes affected specific ecosystems, a team of McGill scientists has analyzed the microscopic remains of plants from this period, found in the sediment of rivers in southern Saskatchewan. In a recent article in "This could be important as we look to the future of global warming, where many scientists have predicted that changes in precipitation could have big impacts on humans and ecosystems," says Peter Douglas from McGill's Department of Earth and Planetary Scientists and senior author on the paper. "At other times of major climate change in Earth's history we typically do see evidence for such changes. The absence of such a signal during the most recent mass extinction event is intriguing."Douglas adds, "Surprisingly, scientists know more about what happened in the oceans at the end-Cretaceous extinction than on land. By clarifying the environmental changes occurring during this period, we narrowed down the factors that are likely to have caused the disappearance of dinosaurs. The research also provides an important analogue for environmental changes humans are causing to the planet, and the potential for future mass extinction."
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Extinction
| 2,020 |
December 14, 2020
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https://www.sciencedaily.com/releases/2020/12/201214192353.htm
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Characterizing wildlife consumers to guide behavior change efforts provides optimism amid the Asian Songbird Extinction Crisis
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A comprehensive new study into the key user groups in Indonesia's bird trade offers hope for protecting species through behavioural change. Novel research led by Manchester Metropolitan University (MMU) and Chester Zoo has identified three main groups within the Indonesian songbird owner community: 'hobbyist', 'contestant' and 'breeder'.
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Indonesia hosts 16% of the worlds bird species and is widely acknowledged as the global epicenter of the wild bird trade. The majority of this trade is concentrated in Java, Indonesia's fourth largest and most populous island. Songbirds, in particular, are highly sought after, with bird owners falling into three main consumer groups: hobbyists, who own birds primarily as pets; contestants, who own birds to enter in singing contests; and breeders, who own birds to breed and/or train for resale or as a pastime.Previous work by lead author Dr. Harry Marshall and his team has suggested that up to 84 million birds are held in captivity on the island of Java alone. Trapping of wild-caught birds in Indonesia and other parts of Southeast Asia has is causing wild bird population declines, a phenomenon known as the 'Asian Songbird Extinction Crisis' (ASC).Dr Marshall said: "The extinction crisis is affecting many countries across Asia, where wild bird populations are facing synergistic pressures from both habitat loss and trapping pressure driven by the demand for pets."This research has uncovered that the consumption behaviour of hobbyists, who represent up to 7 million households, poses the greatest threat to Indonesia's rich avian biodiversity.Stuart Marsden, Professor of Conservation Ecology at MMU, and co-author of the study, said of the largest consumer group: "The large volumes of birds owned by hobbyists, including the largest proportions of potentially wild-caught and threatened birds, are acquired primarily on the basis of convenience and availability, with little importance placed by buyers on their origin."Breeders and contestants generally invested more of their time and money in their birds, whereas hobbyists spent less money.Furthermore, the researchers discovered that contestants exhibit a highly problematic behaviour for conservation, as they show a preference for fashionable species that often fall victim to the spiral of increasing rarity in the wild, rising market value, further demand, and sustained trapping pressure. The results show that behaviour varies significantly between the key groups of the songbird owner community. The high rates of mortality of birds amongst hobbyists indicates pinch-points to target education and demand reduction.Dr Andrew Moss, Lead Conservation Scientist at Chester Zoo, also co-author of the research, said: "Our study provides behavioural change efforts with demographic and geographic profiles to target bird-keepers, who tend to be more affluent and live in the eastern provinces and urban communities. "Dr Marshall, along with a team of 9 Indonesian students from collaborating institution Atma Jaya University Yogyakarta, used a questionnaire survey to collect data from more than 3,000 households across the six provinces of Java. The data collected during this research will be also used as a baseline for future studies to detect changes in behavioural choices and demand as a result of conservation interventions.The team found that hobbyists tended to be middle-aged bird-keepers living in the western provinces, whereas contestants were younger urban bird-keepers employed in business, and breeders were commoner in the eastern provinces, where a strong bird-breeding tradition persists. This shows a clear geographic split between different user-groups, further informing behaviour change efforts.Study co-author Dr Pramana Yuda, Associate Professor in Biology at Atma Jaya University in Yogyakarta, Indonesia, said: "Importantly, our profiles of user-groups will indicate the sources of the biggest threats to wild birds, and guide attempts to reduce its impact on wild populations and their host ecosystems through behaviour change interventions."By further classifying a diverse consumer group, evidence-based conservation efforts such as this can avoid the pitfalls of over-generalising about groups of wildlife consumers, which can complicate demand reduction efforts. However, one limitation highlighted by the authors is that they were unable to sample higher-end consumers due to inaccessibility.Study co-author Dr Alexander Lees, Senior Lecturer at MMU, said: "These consumers could have different characteristics and preferences, perhaps targeting more valuable and harder-to-obtain species such as Javan Green Magpie."By understanding who buys bird, where, why and for how much, future efforts can focus on the 'demarketing' of wild?caught birds.Prof. Nigel Collar, research fellow at BirdLife International and another co-author, said: "Efforts to increase the sustainability of bird-keeping in Java should focus on emphasising the importance of captive-bred birds to hobbyists, whilst also incentivising legitimate breeding enterprises among contestants and breeders."
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Extinction
| 2,020 |
December 14, 2020
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https://www.sciencedaily.com/releases/2020/12/201214192336.htm
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Recovery of an endangered Caribbean coral from parrotfish predation
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Parrotfishes are abundant herbivores that primarily graze upon algae, which may indirectly benefit corals by mitigating coral-algae competition. At a local scale, management efforts to increase populations of parrotfishes are believed to be critically important to maintaining resilient, coral-dominated reefs. Yet, some parrotfish species also occasionally graze coral -- a behavior known as corallivory. Corallivory can cause the partial to total mortality of coral colonies and may have long-term impacts such as reduced coral growth and reproductive capacity and increased susceptibility to disease. While evidence suggests that parrotfishes likely have an overall net positive impact on coral communities, they may have detrimental impacts on heavily predated coral species, such as
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To better understand the consequences of corallivory for The researchers monitored the healing of over 400 parrotfish predation scars on They surveyed the size and abundance of recent parrotfish predation scars present on This study suggests that the immediate negative consequences of parrotfish corallivory for
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Extinction
| 2,020 |
December 9, 2020
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https://www.sciencedaily.com/releases/2020/12/201209115235.htm
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Paleontologists find pterosaur precursors that fill a gap in early evolutionary history
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Here's the original story of flight. Sorry, Wright Brothers, but this story began way before your time -- during the Age of the Dinosaurs.
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Pterosaurs were the earliest reptiles to evolve powered flight, dominating the skies for 150 million years before their imminent extinction some 66 million years ago.However, key details of their evolutionary origin and how they gained their ability to fly have remained a mystery; one that paleontologists have been trying to crack for the past 200 years. In order to learn more about their evolution and fill in a few gaps in the fossil record, it is imperative that their closest relatives are identified.With the help of newly discovered skulls and skeletons that were unearthed in North America, Brazil, Argentina, and Madagascar in recent years, Virginia Tech researchers Sterling Nesbitt and Michelle Stocker from the Department of Geosciences in the College of Science have demonstrated that a group of "dinosaur precursors," called lagerpetids, are the closest relatives of pterosaurs."Where did pterosaurs come from?' is one of the most outstanding questions in reptile evolution; we think we now have an answer," said Sterling Nesbitt, who is an associate professor of geosciences and an affiliated faculty member of the Fralin Life Sciences Institute and the Global Change Center.Their findings were published in Fossils of Dromomeron gregorii, a species of lagerpetid, were first collected in Texas in the 1930s and 1940s, but they weren't properly identified until 2009. Unique to this excavation was a well-preserved partial skull and braincase, which, after further investigation, revealed that these reptiles had a good sense of equilibrium and were likely agile animals.After finding more lagerpetid species in South America, paleontologists were able to create a pretty good picture of what the lagerpetids were; which were small, wingless reptiles that lived across Pangea during much of the Triassic Period, from 237 to 210 million years ago.And in the past 15 years, five research groups from six different countries and three continents have come together to right some wrongs in the evolutionary history of the pterosaur, after the recent discovery of many lagerpetid skulls, forelimbs, and vertebrae from the United States, Brazil, Argentina, and Madagascar.You may be asking yourself, what gave paleontologists the idea to take a closer look at lagerpetids as the closest relatives of pterosaurs? Well, paleontologists have been studying the bones of lagerpetids for quite some time, and they have noted that the length and shape of their bones were similar to the bones of pterosaurs and dinosaurs. But with the few fossils that they had before, it could only be assumed that lagerpetids were a bit closer to dinosaurs.What really caused a shift in the family tree can be attributed to the recently collected lagerpetid skulls and forelimbs, which displayed features that were more similar to pterosaurs than dinosaurs. And with the help of new technological advances, researchers found that pterosaurs and lagerpetids share far more similarities than meet the eye.Using micro-computed tomographic (?CT) scanning to reconstruct their brains and sensory systems within the recently discovered skulls, paleontologists determined that the brains and sensory systems of lagerpetids had many similarities with those of pterosaurs."CT data has been revolutionary for paleontology," said Stocker, who is an assistant professor of vertebrate paleontology and an affiliated faculty member of the Fralin Life Sciences Institute and the Global Change Center."Some of these delicate fossils were collected nearly 80 years ago, and rather than destructively cutting into this first known skull of Dromomeron, we were able to use this technology to carefully reconstruct the brain and inner ear anatomy of these small fossils to help determine the early relatives of pterosaurs."One stark and mystifying finding was that the flightless lagerpetids had already evolved some of the neuroanatomical features that allowed the pterosaurs to fly, which brought forth even more information on the origin of flight."This study is a result of an international effort applying both traditional and cutting-edge techniques," said Martín D. Ezcurra, lead author of the study from the Museo Argentino de Ciencias Naturales in Buenos Aires, Argentina. "This is an example of how modern science and collaboration can shed light on long-standing questions that haunted paleontologists during more than a century."Ultimately, the study will help bridge the anatomical and evolutionary gaps that exist between pterosaurs and other reptiles. The new evolutionary relationships that have emerged from this study will create a new paradigm, providing a completely new framework for the study of the origin of these reptiles and their flight capabilities.With the little information that paleontologists had about early pterosaurs, they had often attributed extremely fast evolution for the acquisition of their unique body plan. But now that lagerpetids are deemed the precursors of pterosaurs, paleontologists can say that pterosaurs evolved at the same rate as other major reptile groups, thanks to the newly discovered "middle man.""Flight is such a fascinating behaviour, and it evolved multiple times during Earth's history," said Serjoscha W. Evers, of the University of Fribourg. "Proposing a new hypothesis of their relationships with other extinct animals is a major step forward in understanding the origins of pterosaur flight."Some questions still remain in this evolutionary mystery. Now that lagerpetids are the closest relatives of pterosaurs, why are they still lacking some of the key characteristics of pterosaurs, including the most outstanding of those -- wings?"We are still missing lots of information about the earliest pterosaurs, and we still don't know how their skeletons transformed into an animal that was capable of flight," said Nesbitt.Nesbitt, Stocker, and a team of Virginia Tech graduate and undergraduate students will continue to study animals that appeared in the Triassic Period -- a period of time in Earth history when many familiar groups of vertebrates, such as dinosaurs, turtles, mammal relatives, and amphibians, first appeared. If and when conditions are safe, they plan on going into the field to collect more fossils from the Triassic Period.Maybe soon, we will have more information to put some finishing touches on the original story of flight.
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Extinction
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November 18, 2020
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https://www.sciencedaily.com/releases/2020/11/201118141831.htm
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Cichlid fishes from African Lake Tanganyika shed light on how organismal diversity arises
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Lake Tanganyika in Africa is a true hotspot of organismal diversity. Approximately 240 species of cichlid fishes have evolved in this lake in less than 10 million years. A research team from the University of Basel has investigated this phenomenon of "explosive speciation" and provides new insights into the origins of biological diversity, as they report in the journal
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The diversity of life on Earth has been shaped by two antagonistic processes: phases of mass extinctions and episodes characterized by the rapid evolution of a multitude of new species. Such outbursts of organismal diversity, also known as "adaptive radiations," are responsible for a substantial part of the biological species on our planet.For instance, most of the animal phyla existing today evolved over the course of the Cambrian radiation about 540 million years ago (also known as Cambrian explosion). What triggered these massive adaptive radiations, and how the process of explosive speciation proceeds in detail, has been largely unknown until now.The cichlid fishes of the African Great Lakes Victoria, Malawi and Tanganyika are among the most impressive examples of "adaptive radiation." Using the cichlid fishes of Lake Tanganyika as a model system, a team of scientists headed by Professor Walter Salzburger from the University of Basel have now investigated in detail the phenomenon of adaptive radiation. On extensive field expeditions to Burundi, Tanzania and Zambia, they collected specimens from virtually all approximately 240 species of cichlid fishes occurring in Lake Tanganyika.Based on this material, they compiled a comprehensive dataset covering information on morphology, ecology, and genetics. For example, the team analyzed body shape and jaw morphology of all species using X-ray imaging and high-resolution computed tomography. The zoologists were particularly interested in the three-dimensional structure of the pharyngeal jaw. This second set of jaws is situated in the pharynx of cichlid fishes and is used to masticate food, allowing the fish to specialize in very specific nutritional niches.Because adaptation to different environments is a central component of adaptive radiation, the researchers also quantified the "ecological niche" used by each species. In collaboration with the Botanical Institute of the University of Basel, they measured the stable carbon and nitrogen isotope composition in the muscle tissue of the fish. These measurements allow to determine in what habitat the fishes lived and what food resources they used. Further, the team sequenced two complete genomes for each and every cichlid species from Lake Tanganyika. Based on this molecular information they were able to reconstruct the complete phylogeny of the cichlids in that lake.Based on their analyses, the scientists could demonstrate that the evolution of cichlid fishes in Lake Tanganyika was not a gradual process, but rather occurred in three discrete pulse-like stages of rapid morphological evolution."Each of these stages was characterized by specialization to a different aspect of the habitat provided by the lake," says lead author Dr. Fabrizia Ronco. The first pulse involved diversification in body shape followed by a pulse in mouth morphology and a final pulse in pharyngeal jaw shape. Especially the pharyngeal jaw has played a key role in the radiation, since its rapid morphological evolution coincided with a high number of speciation events.Through the analysis of the roughly 600 newly sequenced genomes, the Basel researchers showed that the most species-rich and ecologically and morphologically diverse lineages of Tanganyikan cichlids contain species that are genetically more diverse. "Whether an elevated level of genetic diversity is a general feature of highly diverse lineages, or if this pattern is unique to cichlids of Lake Tanganyika, is still unknown," says Salzburger.By studying exceptionally species-rich adaptive radiations, like the African cichlids, scientist can learn more about how biodiversity arises and what factors are associated with it. The present findings of the zoologists from the University of Basel offer new routes to these questions.
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Extinction
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November 17, 2020
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https://www.sciencedaily.com/releases/2020/11/201117192626.htm
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New analysis refutes claim that dinosaurs were in decline before asteroid hit
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A new study from researchers at the University of Bath and Natural History Museum looking at the diversity of dinosaurs shows that they were not in decline at the time of their extinction by an asteroid hit 66 million years ago.
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The researchers say that had the impact not happened, dinosaurs might have continued to dominate the Earth.Dinosaurs were widespread globally at the time of the asteroid impact at the end of the Late Cretaceous period, occupying every continent on the planet and were the dominant form of animal of most terrestrial ecosystems.However, it is still contentious amongst paleobiologists as to whether dinosaurs were declining in diversity at the time of their extinction.In order to address this question, the research team collected a set of different dinosaur family trees and used statistical modelling to assess if each of the main dinosaur groups was still able to produce new species at this time.Their study, published in the journal First author of the study, Joe Bonsor, is undertaking his PhD jointly at the Milner Centre for Evolution at the University of Bath and the Natural History Museum.He said: "Previous studies done by others have used various methods to draw the conclusion that dinosaurs would have died out anyway, as they were in decline towards the end of the Cretaceous period."However, we show that if you expand the dataset to include more recent dinosaur family trees and a broader set of dinosaur types, the results don't actually all point to this conclusion -- in fact only about half of them do."It is difficult to assess the diversity of dinosaurs due to gaps in the fossil record. This can be due to factors such as which bones are preserved as fossils, how accessible the fossils are in the rock to allow them to be found, and the locations where palaeontologists search for them.The researchers used statistical methods to overcome these sampling biases, looking at the rates of speciation of dinosaur families rather than simply counting the number of species belonging to the family.Joe Bonsor said: "The main point of our paper is that it isn't as simple as looking at a few trees and making a decision -- The large unavoidable biases in the fossil record and lack of data can often show a decline in species, but this may not be a reflection of the reality at the time."Our data don't currently show they were in decline, in fact some groups such as hadrosaurs and ceratopsians were thriving and there's no evidence to suggest they would have died out 66 million years ago had the extinction event not happened."Whilst mammal existed at the time of the asteroid hit, it was only due to the extinction of the dinosaurs that led to the niches being vacated, allowing mammals to fill them and later dominate the planet.The research was funded by the Leverhulme Trust and Natural History Museum.
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Extinction
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November 11, 2020
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https://www.sciencedaily.com/releases/2020/11/201111122810.htm
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Largest set of mammalian genomes reveals species at risk of extinction
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An international team of researchers with an effort called the Zoonomia Project has analyzed and compared the whole genomes of more than 80 percent of all mammalian families, spanning almost 110 million years of evolution. The genomic dataset, published today in
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The dataset is aimed at advancing human health research. Researchers can use the data to compare the genomes of humans and other mammals, which could help identify genomic regions that might be involved in human disease. The authors are also making the dataset available to the scientific community via the Zoonomia Project website, without any restrictions on use."The core idea for the project was to develop and use this data to help human geneticists figure out which mutations cause disease," said co-senior author Kerstin Lindblad-Toh, scientific director of vertebrate genomics at the Broad and professor in comparative genomics at Uppsala University.However, in analyzing the new genomes, the authors also found that mammalian species with high extinction rates have less genetic diversity. The findings suggest that sequencing even just a single individual could provide crucial information, in a cost efficient way, on which populations may be at higher risk for extinction and should be prioritized for in-depth assessment of conservation needs."We wrote the paper to talk about this large, unique dataset and explain why it is interesting. Once you make the data widely available and explain its utility to the broader research community, you can really change the way science is done," said co-senior author Elinor Karlsson, director of the Vertebrate Genomics Group at the Broad Institute of MIT and Harvard and professor at the University of Massachusetts Medical School.Zoonomia data have already helped researchers in a recent study to assess the risk of infection with SARS-CoV-2 across many species. The researchers identified 47 mammals that have a high likelihood of being reservoirs or intermediate hosts for the SARS-CoV-2 virus.The Zoonomia Project, formerly called the 200 Mammals Project, builds on a previous project, the 29 Mammals Project, which began sequencing mammalian genomes in 2006. The latest project extends the work by exploring the genomes of species that can perform physiological feats that humans can't, from hibernating squirrels to exceptionally long-lived bats. The project also included genomes of endangered species.In the new study, the researchers collaborated with 28 different institutions worldwide to collect samples for genomic analysis, with the Frozen Zoo at the San Diego Global Zoo providing almost half of the samples. The team focused on species of medical, biological, and biodiversity conservation interest and increased the percentage of mammalian families with a representative genome from 49 to 82.The project also developed and is sharing tools that will enable researchers to look at every "letter" or base in a mammalian genome sequence and compare it to sequences in equivalent locations in the human genome, including regions likely to be involved in disease. This could help researchers identify genetic sites that have remained the same and functional over evolutionary time and those that have randomly mutated. If a site has remained stable across mammals over millions of years, it probably has an important function, so any change in that site could potentially be linked to disease.In releasing the data, the authors call upon the scientific community to support field researchers in collecting samples, increase access to computational resources that enable the analysis of massive genomic datasets, and share genomic data rapidly and openly."One of the most exciting things about the Zoonomia Project is that many of our core questions are accessible to people both within and outside of science," said first author Diane Genereux, a research scientist in the Vertebrate Genomics Group at the Broad. "By designing scientific projects that are accessible to all, we can ensure benefits for public, human, and environmental health."The project was funded in part by the NHGRI, the Swedish Research Council, the Knut and Alice Wallenberg Foundation, Broadnext10, and others.
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Extinction
| 2,020 |
November 2, 2020
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https://www.sciencedaily.com/releases/2020/11/201102155407.htm
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Genomic data 'catches corals in the act' of speciation and adaptation
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A new study led by the University of Hawai'i at Mānoa's Hawai'i Institute of Marine Biology (HIMB) revealed that diversity in Hawaiian corals is likely driven by co-evolution between the coral host, the algal symbiont, and the microbial community.
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As coral reef ecosystems have rapidly collapsed around the globe over the past few decades, there is widespread concern that corals might not be able to adapt to changing climate conditions, and much of the biodiversity in these ecosystems could be lost before it is studied and understood. Coral reefs are among the most highly biodiverse ecosystems on earth, yet it is not clear what drives speciation and diversification in the ocean, where there are few physical barriers that could separate populations.The team of researchers used massive amounts of metagenomic sequencing data to try to understand what may be some of the major drivers of adaptation and variation in corals."Corals have incredible variation with such a wide range of shapes, sizes, and colors that it's really hard for even the best trained experts to be able to sort out different species," said Zac Forsman, lead author of the study and HIMB assistant researcher. "On top of that, some corals lose their algal symbionts, turning stark white or 'bleached' and die during marine heatwaves, while a similar looking coral right next to it seems fine. We wanted to try to better understand what might be driving some of this incredible variation that you see on a typical coral reef."Forsman and colleagues examined genetic relationships within the coral genus Porites, which forms the foundation and builds many coral reefs around the world. They were able to identify genes from the coral, algal symbionts, and bacteria that were most strongly associated with coral bleaching and other factors such as the shape (morphology) of the coral colony. They found relatively few genes associated with bleaching, but many associated with distance from shore, and colony morphologies that dominate different habitats."We sought out to better understand coral bleaching and place it in the context of other sources of variation in a coral species complex. Unexpectedly, we found evidence that these corals have adapted and diverged very recently over depth and distance from shore. The algal symbionts and microbes were also in the process of diverging, implying that co-evolution is involved. It's like we caught them in the act of adaptation and speciation.""These corals have more complex patterns of variation related to habitat than we could have imagined and learning about how corals have diversified over various habitats can teach us about how they might adapt in the future," he explained. "Since variation is the raw material for adaptation, there is hope for the capacity of these corals to adapt to future conditions, but only if we can slow down the pace of loss."
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Extinction
| 2,020 |
October 30, 2020
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https://www.sciencedaily.com/releases/2020/10/201030142129.htm
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To survive asteroid impact, algae learned to hunt
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Tiny, seemingly harmless ocean plants survived the darkness of the asteroid strike that killed the dinosaurs by learning a ghoulish behavior -- eating other living creatures.
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Vast amounts of debris, soot, and aerosols shot into the atmosphere when an asteroid slammed into Earth 66 million years ago, plunging the planet into darkness, cooling the climate, and acidifying the oceans. Along with the dinosaurs on the land and giant reptiles in the ocean, the dominant species of marine algae were instantly wiped out -- except for one rare type.A team of scientists, including researchers at UC Riverside, wanted to understand how these algae managed to thrive while the mass extinction rippled throughout the rest of the global food chain."This event came closest to wiping out all multicellular life on this planet, at least in the ocean," said UCR geologist and study co-author Andrew Ridgwell. "If you remove algae, which form the base of the food chain, everything else should die. We wanted to know how Earth's oceans avoided that fate, and how our modern marine ecosystem re-evolved after such a catastrophe."To answer their questions, the team examined well-preserved fossils of the surviving algae and created detailed computer models to simulate the likely evolution of the algae's feeding habits over time. Their findings are now published in the journal According to Ridgwell, scientists were a bit lucky to find the nano-sized fossils in the first place. They were located in fast accumulating and high-clay-content sediments, which helped preserved them in the same way the La Brea tar pits provide a special environment to help preserve mammoths.Most of the fossils had shields made of calcium carbonate, as well as holes in their shields. The holes indicate the presence of flagella -- thin, tail-like structures that allow tiny organisms to swim."The only reason you need to move is to get your prey," Ridgwell explained.Modern relatives of the ancient algae also have chloroplasts, which enable them to use sunlight to make food from carbon dioxide and water. This ability to survive both by feeding on other organisms and through photosynthesis is called mixotrophy. Examples of the few land plants with this ability include Venus flytraps and sundews.Researchers found that once the post-asteroid darkness cleared, these mixotrophic algae expanded from coastal shelf areas into the open ocean where they became a dominant life form for the next million years, helping to quickly rebuild the food chain. It also helped that larger creatures who would normally feed on these algae were initially absent in the post-extinction oceans."The results illustrate both the extreme adaptability of ocean plankton and their capacity to rapidly evolve, yet also, for plants with a generation time of just a single day, that you are always only a year of darkness away from extinction," Ridgwell said.Only much later did the algae evolve, losing the ability to eat other creatures and re-establishing themselves to become one of the dominant species of algae in today's ocean."Mixotrophy was both the means of initial survival and then an advantage after the post-asteroid darkness lifted because of the abundant small pretty cells, likely survivor cyanobacteria," Ridgwell said. "It is the ultimate Halloween story -- when the lights go out, everyone starts eating each other."
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Extinction
| 2,020 |
October 29, 2020
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https://www.sciencedaily.com/releases/2020/10/201029105011.htm
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Shining a (UV) light on the glow-in-the-dark platypus
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The fur of the platypus -- an Australian species threatened with extinction -- glows green under ultraviolet light, a new study finds. This is the first observation of biofluorescence in an egg-laying mammal (monotreme), suggesting this extraordinary trait may not be as rare as previously thought.
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The research article "Biofluorescence in the platypus (Two mammals -- the opossum and the flying squirrel -- are already known to have fur that biofluoresces under under ultraviolet (UV) light.One of the paper's authors discovered pink biofluorescence in flying squirrels by accident while conducting a night survey for lichens, a finding reported in an earlier paper. While confirming this field observation with preserved museum specimens, the researchers decided to examine the platypuses in the next drawer along too.They studied three museum platypus specimens: a female and a male from the Field Museum of Natural History in Chicago and another male specimen from the University of Nebraska State Museum.In visible light, the fur of all three platypus specimens was uniformly brown. But under UV light they appeared green or cyan. The fur of the platypus absorbs UV (wavelengths of 200-400 nanometers) and re-emits visible light (of 500-600 nanometers), making it fluoresce.Like the marsupial opossum and the placental flying squirrel, platypuses are most active during the night and at dawn and dusk. It may be that these mammals -- and possibly others -- developed biofluorescence to adapt to low light conditions. The researchers suggest this may be a way for platypuses to see and interact with each other in the dark.The researchers would now like to work with an Australian team to observe biofluorescence in wild animals. And with colleagues at Northland College and Colorado State University, they are working on a project to further explore the phenomenon across the mammalian family tree."It was a mix of serendipity and curiosity that led us to shine a UV light on the platypuses at the Field Museum," said lead author Professor Paula Spaeth Anich, Associate Professor of Biology and Natural Resources at Northland College. "But we were also interested in seeing how deep in the mammalian tree the trait of biofluorescent fur went. It's thought that monotremes branched off the marsupial-placental lineage more than 150 million years ago. So, it was intriguing to see that animals that were such distant relatives also had biofluorescent fur."
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Extinction
| 2,020 |
October 22, 2020
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https://www.sciencedaily.com/releases/2020/10/201022151745.htm
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Tackling alarming decline in nature requires 'safety net' of multiple, ambitious goals
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A "safety net" made up of multiple ambitious and interlinked goals is needed to tackle nature's alarming decline, according to an international team of researchers analyzing the new goals for biodiversity being drafted by the UN's Convention on Biological Diversity (CBD).
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The scientific advice comes at a critical time: The CBD recently announced that none of its 20 biodiversity targets for 2020, which were set in 2010, has been fully reached. Policymakers, scientists and other experts are now preparing for the next generation of biodiversity goals, which will be unveiled at the CBD's Convention of the Parties in 2021."To curb the many threats to our biological world, we need biodiversity targets that are distinct, manifold and appreciate different facets of biodiversity," Amy Zanne, associate professor of biological sciences at the George Washington University and a member of the international team of researchers who analyzed the new biodiversity goals, said. "Evolutionary diversity, for example, may be a harder concept to neatly portray in a simple biodiversity target but it is critical that we acknowledge that some species are evolutionarily distinct -- they hold a unique and irreplaceable position within the Tree of Life and their preservation should be prioritized."On August 17, 2020, the CBD released a draft of their post-2020 biodiversity goals. The research team, which included more than 60 leading biodiversity experts from 26 countries, assessed the goals and asked a number of questions, including what scientific evidence supported them, how the goals reinforced or undermined each other, and whether one aspect of nature could serve as a shortcut for others. Their independent assessment was published today in the journal Science."We hope this is a useful tool in the CBD negotiations on a new strategy for nature and people," Sandra Díaz, a professor at the National University of Córdoba and lead author of the paper, said.According to the researchers, member nations of the CBD should consider three critical points when setting new biodiversity goals:"Building a sufficiently ambitious safety net for nature will be a major global challenge," Díaz said. "But unless we do it, we are leaving huge problems for every future generation."The researchers note they explicitly focused on the biological aspects of the draft goals and did not evaluate the economic or political consequences. They say, however, that not considering social and political issues when implementing new goals would be a recipe for failure.In the new paper, GW's Zanne urged that different kinds of diversity be considered when setting biodiversity targets, which is reflected in the paper's supplement under "Species extinctions -- risks, roles and history."
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Extinction
| 2,020 |
October 15, 2020
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https://www.sciencedaily.com/releases/2020/10/201015101809.htm
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Was Hong Kong once a coral reef paradise?
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Researchers from The University of Hong Kong's School of Biological Sciences and The Swire Institute of Marine Science, have for the first time investigated the historical presence of coral communities in the Greater Bay Area, revealing a catastrophic range collapse and loss of diversity that occurred in the last several decades.
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The research, published in the journal "The data we collect helps us to create a sort of fossil time machine," said Cybulski. "As corals grow naturally, parts of them will break off and fall to seafloor becoming a part of the sediment. Over time, many different layers of these coral skeletons will stack on top of one another. With a bit of effort we can core through the sediments and collect the different layers and reveal what coral communities were like through time," Cybulski explained. By using this method, the team was able to collect skeletons from over 5,000 years ago, which they determined thanks to radiocarbon dating by collaborator Dr Yusuke YOKOYAMA of the Atmosphere and Ocean Research Institute at The University of Tokyo.When the team compared their fossil data to a modern-day dataset collected by collaborators at Baptist University -- Dr Jian Wen QIU and Dr James XIE, several striking conclusions were revealed. First, there has been about a 40% decrease in the number of different corals living in Southern Hong Kong waters. Second, the greatest loss was of the ecologically important yet highly-sensitive staghorn corals (Acropora), which now only lives in an area about 50% smaller than its historic range. Finally, the greatest impact and losses of corals occurred in waters that are closest to the Pearl River Estuary in the southwest and Tolo Harbor in the Northeast. Based on the data, the teams best guess for the timing of this coral community change is conservatively within the last century, but likely within the past few decades. The overall conclusion: poor water quality driven by increased development and lack of proper treatment is presently the regions greatest threat to the survival of corals."This trend we saw of a diversity decline and the loss of Acropora is consistent with other research in different areas of the world," Cybulski continues: "It's particularly bad news for this region, as Acropora represents the only type of coral that is complex, and creates physical space that promotes greater biodiversity. The loss of this coral is similar to losing all the big trees in a forest." However, similar to trees in a forest, Cybulski continued by saying there is hope for Hong Kong's corals through conservation efforts.Indeed, this historical research has already played a critical role in protecting and restoring corals locally. In July earlier this year, PhD Candidate Ms Vriko YU, also of the Baker Lab at HKU, pioneered a coral restoration project in Hoi Ha Wan Marine Park (Note 1). This project aims to restore and better understand what it will take to save Hong Kong corals, and was made possible due to the water quality improvements in the bay by the local government.Using Cybulski's historical data to infer the appropriate steps needed, the team is now returning corals such as Acropora that previously thrived in Hoi Ha, back to their proper home. To date, 100% of the reintroduced coral have survived. Furthermore, the team has documented several coral associated invertebrates at the site, showing that this restored habitat is indeed increasing biodiversity. The team feels this multi-faceted model -- historical research that identifies major stress targets for local improvements -- can be used by other researchers who hope to give corals their greatest chance for future survival.
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Extinction
| 2,020 |
October 14, 2020
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https://www.sciencedaily.com/releases/2020/10/201014082804.htm
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Scientists shed new light on viruses' role in coral bleaching
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Scientists at Oregon State University have shown that viral infection is involved in coral bleaching -- the breakdown of the symbiotic relationship between corals and the algae they rely on for energy.
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Funded by the National Science Foundation, the research is important because understanding the factors behind coral health is crucial to efforts to save the Earth's embattled reefs -- between 2014 and 2017 alone, more than 75% experienced bleaching-level heat stress, and 30% suffered mortality-level stress.The planet's largest and most significant structures of biological origin, coral reefs are found in less than 1% of the ocean but are home to nearly one-quarter of all known marine species. Reefs also help regulate the sea's carbon dioxide levels and are a vital hunting ground that scientists use in the search for new medicines.Since their first appearance 425 million years ago, corals have branched into more than 1,500 species. A complex composition of dinoflagellates -- including the algae symbiont -- fungi, bacteria, archaea and viruses make up the coral microbiome, and shifts in microbiome composition are connected to changes in coral health.The algae the corals need can be stressed by warming oceans to the point of dysbiosis -- a collapse of the host-symbiont partnership.To better understand how viruses contribute to making corals healthy or unhealthy, Oregon State Ph.D. candidate Adriana Messyasz and microbiology researcher Rebecca Vega Thurber of the OSU College of Science led a project that compared the viral metagenomes of coral colony pairs during a minor 2016 bleaching event in Mo'orea, French Polynesia.Also known as environmental genomics, metagenomics refers to studying genetic material recovered directly from environmental samples, in this case samples taken from a coral reef.For this study, scientists collected bleached and non-bleached pairs of corals to determine if the mixes of viruses on them were similar or different. The bleached and non-bleached corals shared nearly identical environmental conditions."After analyzing the viral metagenomes of each pair, we found that bleached corals had a higher abundance of eukaryotic viral sequences, and non-bleached corals had a higher abundance of bacteriophage sequences," Messyasz said. "This gave us the first quantitative evidence of a shift in viral assemblages between coral bleaching states."Bacteriophage viruses infect and replicate within bacteria. Eukaryotic viruses infect non-bacterial organisms like animals.In addition to having a greater presence of eukaryotic viruses in general, bleached corals displayed an abundance of what are called giant viruses. Known scientifically as nucleocytoplasmic large DNA viruses, or NCLDV, they are complex, double-stranded DNA viruses that can be parasitic to organisms ranging from the single-celled to large animals, including humans."Giant viruses have been implicated in coral bleaching," Messyasz said. "We were able to generate the first draft genome of a giant virus that might be a factor in bleaching."The researchers used an electron microscope to identify multiple viral particle types, all reminiscent of medium- to large-sized NCLDV, she said."Based on what we saw under the microscope and our taxonomic annotations of viral metagenome sequences, we think the draft genome represents a novel, phylogenetically distinct member of the NCLDVs," Messyasz said. "Its closest sequenced relative is a marine flagellate-associated virus."The new NCLDV is also present in apparently healthy corals but in far less abundance, suggesting it plays a role in the onset of bleaching and/or its severity, she added.
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Extinction
| 2,020 |
October 8, 2020
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https://www.sciencedaily.com/releases/2020/10/201008121259.htm
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Scientists reconstruct beetles from the Cretaceous
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About a year ago, researchers found fossil specimens of beetles in an amber deposit in Myanmar, thereby describing a new beetle family that lived about 99 million years ago. However, the scientists had not been able to fully describe the morphology of the insects in the amber sample, which is why the beetles were subsequently given the mysterious name Mysteriomorphidae. An international research team led by the University of Bonn (Germany) and Palacky University (Czech Republic) has now examined four newly found specimens of the Mysteriomorphidae using computer tomography and has been able to reconstruct them. The results allow to draw conclusions about the evolution of the species during the Cretaceous period. The study has been published in the journal
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Small creatures enclosed in amber can provide scientists with important information about past times, some of which date back many millions of years. In January 2019, the Spanish paleontologist Dr. David Peris, one of the two main authors of the study, collected several amber samples from the northern state of Kachin in Myanmar during a scientific trip to China and found beetle specimens from the same group as the Mysteriomorphidae.Some of the newly found specimens showed a very good state of preservation - a good prerequisite for David Peris and his colleagues to carry out a virtual reconstruction of one of the beetles using computer tomography (CT scan). The technique used in paleontology allows researchers to study many small features of the fossils - even internal structures such as genitalia, if preserved.While David Peris and his colleagues started to study and describe the morphology, i.e. the outer shape of the beetles, another research group also described the new family of Mysteriomorphidae by means of further specimens, that also came from the amber deposit in Myanmar. "However, the first study left some open questions about the classification of these fossils which had to be answered. We used the opportunity to pursue these questions with new technologies," explains David Peris, researcher now at the Institute for Geosciences and Meteorology at the University of Bonn."We used the morphology to better define the placement of the beetles and discovered that they were very closely related to Elateridae, a current family," explains Dr. Robin Kundrata from Palacky University, the second main author of the study and also an expert on this group of beetles. The scientists discovered important diagnostic characters that these beetle lineages share on mouthparts, thorax and abdomen.Apart from the morphology, the researchers also analyzed the evolutionary history of the beetles. Earlier models had suggested that the beetles had a low extinction rate throughout their long evolutionary history, even during the Cretaceous period. However, the researchers provided a list of fossil groups of beetles described from the Cretaceous amber findings that, as Mysteriomorphidae, are only known as fossils from that time and had not survived the end of the Cretaceous period.Background: During the Cretaceous period, flowering plants spread all over the world, replacing the old plants in the changing environment. This distribution of plants was connected with new possibilities for many associated animals and also with the development of new living beings, for example pollinators of flowers. However, most previous theories had not described that the animal species that were previously well adapted to the old plants were under pressure to adapt to the new resources and possibly became extinct. "Our results support the hypothesis that beetles, but perhaps some other groups of insects, suffered a decrease in their diversity during the time of plant revolution," states David Peris.
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Extinction
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October 7, 2020
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https://www.sciencedaily.com/releases/2020/10/201007123049.htm
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Long-term consequences difficult to predict
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A research team has investigated the consequences of changes in plant biodiversity for the functioning of ecosystems. The scientists found that the relationships between plant traits and ecosystem functions change from year to year. This makes predicting the long-term consequences of biodiversity change extremely difficult.
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"We found that -- over the longer term -- the links between plant traits and ecosystem functions were indeed very weak, as we could only explain about 12 per cent of the variance in ecosystem functioning," said the paper's lead author, Dr Fons van der Plas from the Institute of Biology at Leipzig University. Together with colleagues from the German Centre for Integrative Biodiversity Research (iDiv) and other research institutions in Germany and abroad, he found different patterns than in previous studies -- which had focused on short-term links between plant traits and ecosystem functions. These had previously assumed much stronger links between plant traits and ecosystem functioning."The main difference between our studies and earlier ones was that we carried out our work over a period of ten years, while most other studies were based on data measured in just one year," said the biologist. The relationships between plant traits and ecosystem functions changed from year to year: some species become locally extinct, while others replace them.Scientists often ask themselves how this change in biodiversity affects the way ecosystems function, for example in terms of biomass production, carbon sequestration and pollination. In predicting these consequences, they rely on the traits in which plants differ. For example, some plant species are pollinated by insects, and others by the wind. They hope that knowing which species will be more common in the future and what traits these species have will enable them to make more precise predictions.The research team led by van der Plas has now discovered, for example, that plant biomass production was maximised in plant communities dominated by species with thick roots in some years and by completely different plant communities in others. In almost every year, a different plant trait was found to have been important for maximising biomass production. According to van der Plas, it is therefore extremely difficult to predict exactly how changes in plant communities affect the functioning of ecosystems over long periods of time.
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Extinction
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October 5, 2020
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https://www.sciencedaily.com/releases/2020/10/201005005923.htm
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Body size of the extinct Megalodon indeed off the charts in the shark world
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A new study shows that the body size of the iconic gigantic or megatooth shark, about 15 meters (50 feet) in length, is indeed anomalously large compared to body sizes of its relatives.
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Formally called Otodus megalodon, the fossil shark that lived nearly worldwide roughly 15-3.6 million years ago is receiving a renewed look at the significance of its body size in the shark world, based on a new study appearing in the international journal Otodus megalodon is commonly portrayed as a super-sized, monstrous shark, in novels and films such as the 2018 sci-fi thriller "The Meg," but it is known that the scientifically justifiable maximum possible body size for the species is about 15 meters (50 feet). Nonetheless, it is still an impressively large shark, and the new study illuminates exactly how uniquely gigantic the shark was, according to Kenshu Shimada, a paleobiologist at DePaul University in Chicago and lead author of the study.Otodus megalodon belongs to the shark group called lamniforms with a rich fossil record, but the biology of extinct forms is poorly understood because these cartilaginous fishes are mostly known only from their teeth. Based on measurements taken from present-day non-planktivorous lamniforms, the study presents an equation that would allow estimations about the body length of extinct forms from their teeth. The study demonstrates that O. megalodon that reached about 15 meters (50 feet) is truly an outlier because practically all other non-planktivorous sharks have a general size limit of 7 meters (23 feet), and only a few plankton-eating sharks, such as the whale shark and basking shark, were equivalent or came close to the size. The study also reveals that the Cenozoic Era (after the age of dinosaurs, including today) saw more lamniform lineages attaining larger sizes than the Mesozoic (age of dinosaurs) Era.Warm-bloodedness has previously been proposed to have led to the gigantism (over 6 meters, or 20 feet) in multiple lamniform lineages. The new study proposes their live-bearing reproductive strategy with a unique cannibalistic egg-eating behavior to nourish early-hatched embryos to large sizes inside their mother to be another possible cause for the frequent evolution of gigantism achieved by lamniform sharks.Understanding body sizes of extinct organisms is important in the context of ecology and evolution. "Lamniform sharks have represented major carnivores in oceans since the age of dinosaurs, so it is reasonable to assert that they must have played an important role in shaping the marine ecosystems we know today," said Shimada."This is compelling evidence for the truly exceptional size of megalodon," noted co-author Michael Griffiths, a professor of environmental science at William Paterson University in Wayne, New Jersey. Co-author Martin Becker, also a professor of environmental science at William Paterson University, added, "this work represents a critical advancement in our understanding of the evolution of this ocean giant."
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Extinction
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