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March 4, 2019
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https://www.sciencedaily.com/releases/2019/03/190304121508.htm
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How new species arise in the sea
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For a new species to evolve, two things are essential: a characteristic -- such as a colour -- unique to one species and a mating preference for this characteristic. For example, individuals from a blue fish species prefer blue mates and individuals from a red fish species prefer red mates. If the two species interbreed, the process of sexual recombination is expected to destroy the coupling between colour and mate preferences and form red individuals with a preference for blue mates and vice versa. This will prevent the two species from diverging, and this is one of the reasons why it has been thought for a long time that new species can only evolve in absolute isolation, without interbreeding.
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However, the dynamics of this process depend on the exact number and location of genes underlying species characteristics and mate preferences, the strength of natural selection acting on these genes, and the amount of interbreeding between species. In a new study, Professor Oscar Puebla from GEOMAR Helmholtz Centre for Ocean Research Kiel in Germany together with colleagues from the Smithsonian Tropical Research Institute in Panama have found that natural selection can couple the evolution of genes for colour pattern and mate preferences when species still interbreed. The study has been published today in the international journal "To address this question, the first challenge was to identify an animal group in which species are still young and interbreed, with clear species characteristics, and in which the bases of reproductive isolation are well understood," Oscar Puebla explains. The hamlets, a group of closely related reef fishes from the wider Caribbean, constitute exactly such a group. The hamlets are extremely close genetically, differ essentially in terms of colour pattern, and are reproductively isolated through strong visually-based mate preferences.A second difficulty consists in identifying the genes that underlie species differences and mate preferences. The authors of the new study have assembled a reference genome for the hamlets and sequenced the whole genomes of 110 individuals from three species in Panama, Belize and Honduras. "This powerful dataset allowed us to identify four narrow regions of the genome that are highly and consistently differentiated among species in a backdrop of almost no genetic differentiation in the rest of the genome," co-author Kosmas Hench from GEOMAR says. In line with the ecology and reproductive biology of the hamlets, these four intervals include genes involved in vision and colour pattern.The data also show that vision and colour pattern genes remain coupled despite the fact that they are located on three different chromosomes and that species still interbreed. Such a coupling had been previously reported when the two sets of genes are very close to each other on chromosomes, in which case they are protected from sexual recombination, but not when they are on different chromosomes. By capturing the very earliest stages of speciation in hamlets, the team shows how selection can contribute to the creation of new species."A lot of closely related coral reef fishes differ in little else but color and pattern," said Owen McMillan, co-author and academic dean at the Smithsonian Tropical Research Institute. "I fully expect that the discoveries we have made in hamlets will apply to other forms of life and may ultimately explain the remarkable diversity of fishes on coral reefs around the world."
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March 1, 2019
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https://www.sciencedaily.com/releases/2019/03/190301123242.htm
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Bacteria in frog skin may help fight fungal infections in humans
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In the past few decades, a lethal disease has decimated populations of frogs and other amphibians worldwide, even driving some species to extinction. Yet other amphibians resisted the epidemic. Based on previous research, scientists at the INDICASAT AIP, Smithsonian and collaborating institutions knew that skin bacteria could be protecting the animals by producing fungi-fighting compounds. However, this time they decided to explore these as potential novel antifungal sources for the benefit of humans and amphibians.
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"Amphibians inhabit humid places favoring the growth of fungi, coexisting with these and other microorganisms in their environment, some of which can be pathogenic," said Smithsonian scientist Roberto Ibáñez, one of the authors of the study published in The team first travelled to the Chiriquí highlands in Panama, where the chytrid fungus, responsible for the disease chytridiomycosis, has severely affected amphibian populations. They collected samples from seven frog species to find out what kind of skin bacteria they harbored."Amphibians have glands scattered on their skin that produce different compounds," Ibáñez said. "In addition, their skin is inhabited by a diverse community of bacteria that produce metabolites that inhibit the growth of fungi and other bacteria."Back in the laboratory, 201 bacterial strains were retrieved from their samples and tested against After identifying the most promising bacteria, the scientists had a new question: among all the chemical compounds produced by The team then separated viscosin from the other components produced by This research project holds promise for humans and frogs. Studying the skin bacteria of Panamanian frogs may lead to the development of alternative drugs to treat the fungi causing aspergillosis in humans, which are becoming more drug-resistant, and to defy the chytridiomycosis epidemic, the major source of disease-related death among amphibians worldwide."We are showing to the scientific community a set of possible alternative molecules to fight fungal drug resistance in humans," said Christian Martin, the first author of the study along with the principal investigator Marcelino Gutiérrez, both from INDICASAT. "Although more studies are needed, our collaboration could spark interest in the conservation of amphibians as a novel source of bioactive compounds in humans. For amphibians, this is a promising study because there are only four bacterial secondary metabolites chemically described that inhibit chytrid fungi. In this study, we are introducing a new family of chemical compounds found in Panamanian frogs that could help amphibians worldwide.""I consider that bioprospecting compounds from skin secretions or bacteria living in frog's skins is just beginning," Ibáñez said. "This research has identified an antifungal compound produced by frog skin bacteria, which may be used to control pathogenic fungi affecting humans and amphibians. More research will be required to determine its potential medicinal use."
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March 1, 2019
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https://www.sciencedaily.com/releases/2019/03/190301101830.htm
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Paleontology: Diversification after mass extinction
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A team led by Ludwig-Maximilians-Universitaet (LMU) in Munich paleontologist Adriana López-Arbarello has identified three hitherto unknown fossil fish species in the Swiss Alps, which provide new insights into the diversification of the genus
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Monte San Giorgio in the Swiss canton of Ticino is one of the most important known sources of marine fossils from the Middle Triassic Period (around 240 million years ago). The new and exquisitely preserved fossil fish specimens, which Dr. Adriana López-Arbarello (a member of the Institute of Paleontology and Geobiology and of the Geobiocenter at LMU) has been studying in collaboration with colleagues based in Switzerland were also discovered in these dolomites and limestones. As the researchers now report in the online journal The first member of the genus These findings provide new insights into the evolution of the genus. "Our phylogenetic analyses demonstrate that
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February 28, 2019
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https://www.sciencedaily.com/releases/2019/02/190228093626.htm
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Reduced salinity of seawater wreaks havoc on coral chemistry
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New research confirms that drastic changes in ocean salinity from, for example, severe freshwater flooding, as recently experienced off the coast of north-east Queensland from abnormal monsoonal conditions, provoke a similar stress response in corals as extreme heating, resulting in "freshwater bleaching" and if unabated, coral death.
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Researchers from the ARC Centre of Excellence for Coral Reef Studies at James Cook University (Coral CoE) and University of Technology Sydney (UTS) report that extreme and sudden changes in salinity, or the ocean salt concentration, cause a biochemical response in corals that is similar to marine heatwaves, but in some ways, more damaging to their cells ability to function."Corals are sensitive organisms, known to only tolerate slight changes in their environment. Thriving in clear, sunlit waters -- the majority of reef-building corals are found in tropical and subtropical waters with a salinity between 32 to 42 parts per thousand," said senior author Prof David Miller of Coral CoE."During the recent flooding, there are reports that nearshore reefs were exposed to roughly half the normal ocean salinity.""Our research shows that this kind of environmental change causes a shock response in corals that prevents normal cell function."The researchers used the sequenced genome -- a biological blueprint -- of the common reef-building coral, "Using the sophisticated labs at the National Sea Simulator, we put both young and adult corals under a salinity stress test to see how they respond to differing salinity concentrations," said co-author Dr Jean-Baptiste Raina of UTS."We found that there was a common response between both coral life-stages -- with the younger corals being more sensitive to low salinity conditions, but faring slightly better with exposure over time.""In general, we found that the coral's cells launch a similar chemical response to reduced salinity as they do for heat stress," Prof Miller explained."However, unlike the heat stress response, corals exposed to reduced salinity experience a complete collapse of their internal cellular protein balance, suggesting that their cells are in deep trouble."Although the central Great Barrier Reef may have been spared mass thermal bleaching due to higher-than-normal ocean temperatures this summer, there are many coastal reefs left battling dramatic changes in water conditions from the massive plumes of floodwater.With the frequency and severity of heavy rainfall and runoff events predicted to increase by 2050, management interventions to increase the resilience of reefs are needed now more than ever.
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Extinction
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February 27, 2019
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https://www.sciencedaily.com/releases/2019/02/190227142733.htm
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Ancient extinct sloth tooth in Belize tells story of creature's last year
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Some 27,000 years ago in central Belize, a giant sloth was thirsty. The region was arid, not like today's steamy jungle. The Last Glacial Maximum had locked up much of Earth's moisture in polar ice caps and glaciers. Water tables in the area were low.
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The sloth, a beast that stood up to 4 meters tall, eventually found water -- in a deep sinkhole with steep walls down to the water. That is where it took its final drink. In 2014, divers found some of the sloth's remains -- parts of a tooth, humerus and femur -- while searching for ancient Maya artifacts in the pool, in Cara Blanca, Belize.Though partially fossilized, the tooth still held enough unaltered tissue for stable carbon and oxygen isotope analysis, which provided clues to what the sloth ate in the last year of its life. This, in turn, revealed much about the local climate and environment of the region at the time. The findings, reported in the journal "We began our study with the hopes of gaining a better understanding of the landscape within which large mammals went extinct and humans emerged in central Belize," said University of Illinois graduate student Jean T. Larmon, who led the research with U. of I. anthropology professors Lisa Lucero and Stanley Ambrose. "In the process, we discovered which part of the tooth had best maintained its integrity for analysis. And we refined methods for studying similar specimens in the future."The new findings "add to the evidence that many factors, in addition to a changing climate, contributed to the extinction of megafauna in the Americas," said Lucero, who studies the ancient Maya of central Belize. "One of those potential factors is the arrival of humans on the scene 12,000 to 13,000 years ago."The teeth of giant sloths like the one found in Belize, "Giant sloth teeth have no enamel, the hard, outer layer of human and some animal teeth that can be analyzed to learn about their diet," she said.Other factors have limited scientists' ability to study the teeth of ancient sloths. Most are fossilized, with minerals replacing much or all of the original tissue and bone.By using cathodoluminescence microscopy, a technique that causes minerals to glow and can detect the extent of mineralization in fossils, the researchers discovered that one type of tooth tissue, the dense orthodentin, was largely intact.Larmon drilled 20 samples of orthodentin for isotopic analysis along the 10-centimeter-long tooth fragment, spanning more than a year of tooth growth."This allowed us to trace monthly and seasonal changes in the sloth's diet and climate for the first time, and also to select the best part of the tooth for reliable radiocarbon dating," Ambrose said.The isotopic analysis revealed that the giant sloth lived through a long dry season, which lasted about seven months, sandwiched between two short rainy seasons. The analysis also revealed that the creature lived in a savanna, rather than a forest, and consumed a variety of plants that differed between wet and dry seasons."We were able to see that this huge, social creature was able to adapt rather readily to the dry climate, shifting its subsistence to relying upon what was more available or palatable," Larmon said."This supports the idea that the sloths had a diverse diet," Lucero said. "That helps explain why they were so widespread and why they lasted so long. It's likely because they were highly adaptable."The National Science Foundation and the University of Illinois supported this research.
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Extinction
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February 27, 2019
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https://www.sciencedaily.com/releases/2019/02/190227111109.htm
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Human settlements and rainfall affect giraffe home ranges
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Giraffes that live close to densely populated towns have larger home ranges than giraffes that live far from towns, according to a new study by an international team of wildlife researchers from the University of Zürich, Penn State, and the Wild Nature Institute. This suggests that the giraffes in human-impacted areas need to travel longer distances -- and expend more energy -- to obtain critical resources. The researchers found that average rainfall also impacts giraffe home ranges, which are smaller in areas with more rain. The study was published February 22, 2019 in the journal
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"Giraffes are huge browsing animals that live in African savanna ecosystems where they must find everything they need to survive and reproduce in landscapes increasingly impacted by human activities," said Derek E. Lee, associate research professor of biology at Penn State and principal scientist of the Wild Nature Institute. "People are converting natural savannas to towns and farms, and cutting trees for fuelwood and charcoal industries, all of which potentially degrade giraffe habitat."The team quantified home range sizes -- the spatial area over which an animal repeatedly travels in search of food, water, shelter and mates -- for 71 adult giraffes from data collected over six years in the spatially heterogeneous Tarangire Ecosystem of Tanzania. They examined correlations between individual home range sizes and environmental and anthropogenic -- human related -- factors, to better understand the mechanisms driving space use of this threatened megaherbivore.Home range behavior is an expression of an animal's decision-making process about how to access the resources needed for survival and reproduction. The researchers found that giraffes that lived closer to large human settlements had larger home-ranges. No such relationship was evident with bomas, which are homesteads built by indigenous livestock-keeping Maasai people, suggesting that giraffes are tolerant of more traditional, lower-impact land uses."Giraffes are vulnerable to extinction after a 40 percent population decline during the past three decades," said Mara Knüsel, a graduate student at the University of Zurich and first author of the study. "Identifying factors affecting space use help wildlife conservationists to make better decisions for at-risk species such as giraffes."As one of the largest herbivores on earth, giraffes have a profound impact on plant populations, vegetation structure, and ecosystem processes where they live. Giraffes are also a favorite animal sought by ecotourists on safari in Tanzania, where the safari industry is the largest economic sector in the country."Most studies that previously looked at home ranges of giraffes didn't look for environmental factors that determine the observed home range size, so this study goes beyond the pattern to reveal the process behind it," said Monica Bond, PhD candidate at the University of Zürich and senior author of the study.The research team also compared home range estimates from published data for eight giraffe populations across Africa and examined the relationship between giraffe home range size and mean annual rainfall as a potential explanation for observed variation in space use among populations. Rainfall was negatively correlated with home range size -- giraffes in areas with less rainfall had larger home ranges."This relationship between rainfall and space use by a large herbivore is not surprising, given that rainfall is the main driver of vegetation productivity and thus food availability," said Lee. "Greater availability and access to critical resources such as food and water leads to smaller home range sizes.""Human disturbance and fragmentation of habitat in and around densely populated areas likely reduced the local forage and water resources available for giraffes, forcing individuals to increase their movements and use of space to obtain these resources," said Knüsel. "Similarly, lower rainfall and lower primary productivity forces individuals to range more widely."
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Extinction
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February 27, 2019
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https://www.sciencedaily.com/releases/2019/02/190227081545.htm
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Oldest frog relative found in North America
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A team of paleontologists led by Virginia Tech's Michelle Stocker and Sterling Nesbitt of the Department of Geosciences have identified fossil fragments of what are thought to be the oldest known frogs in North America.
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The fossils are comprised of several small pieces of hip bone, called an ilium, from Chinle frogs, a distant long-extinct branch of, but not a direct ancestor of, modern frogs. The fragments are packed into rock and are smaller than a pinky nail. They represent the first known and earliest equatorial remains of a salientian -- the group containing living frogs, and their most-closely related fossil relatives -- from the Late Triassic, roughly 216 million years ago.The name of the fossil derives from where they were found, the Chinle Formation of Arizona.Stocker, an assistant professor of geosciences in the Virginia Tech College of Science, says the fossils, discovered in May 2018, underscore the importance of microfossil collection and analysis for understanding extinct species whose total length is under three feet in length."This new find highlights just how much there is still to learn about the Late Triassic ecosystem, and how much we find when we just look a little closer," Stocker said. "We're familiar with the charismatic archosaurs from the Chinle Formation, but we know that based on other ecosystems, they should make up a small percentage of the animals that lived together. With this new focus we're able to fill in a lot of those missing smaller components with new discoveries."Coming from multiple individuals, the hip bones are are long and hollow, with a hip socket offset rather than centered. The bones of the frogs show how tiny they were: Just a bit over half-an-inch long. "The Chinle frog could fit on the end of your finger," Stocker added.Stocker and her team include researchers from Virginia Tech, Arizona's Petrified Forest National Park, and the University of Florida's Museum of Natural History, with the findings published today in the online journal "We refrain from naming this Chinle frog because we are continuing to process microvertebrate matrix that will likely yield additional skull and postcranial material that has the potential to be even more informative," Stocker added.The Chinle frog shares more features with living frogs and Added Nesbitt, also an assistant professor of geosciences, "Now we know that tiny frogs were present approximately 215 million years ago from North America, we may be able to find other members of the modern vertebrate communities in the Triassic Period."(During the Triassic, the separate continents we recognize today formed the single landmass named Pangaea. Present-day Arizona was located roughly 10 degrees north of the equator.)The team added this discovery also marks the first time that frog fossils have been found directly with phytosaurs, and other early dinosaurs.The Virginia Tech team included both undergraduate and graduate students from across the university, using fossils found in the field and dousing additional rock samples repeatedly in water buckets. Further study of the fossils was completed by CT scans. The undergraduates who accompanied Stocker and Nesbitt on the spring 2018 expedition to Arizona included Elizabeth Evans, a major in the School of Performing Arts; Rebecca Hawkins, majoring in the Department of Fish and Wildlife Conservation; and Hector Lopez, majoring in biological sciences."Through my internship with Drs. Stocker and Nesbitt in Arizona, I learned firsthand the hard work that paleontologists put into finding fossils," said Hawkins, a sophomore in the College of Natural Resources and Environment. "Every day you have to brave long treks, heavy loads, scorching heat, and more. But, with just the right combination of patience and luck, you can find something truly amazing that makes the toil worth it, like a tiny frog hip that tells a big story.""Our development of methods that recover delicate bones from small-bodied vertebrates enabled this exciting discovery," said Ben Kligman, a Ph.D. student in Geosciences from Philadelphia, Pennsylvania. "Our aim is to use similar techniques in the Chinle Formation to uncover the early history of other small-bodied animals including lizards, salamanders, turtles, and mammals."Funding for the study came from the National Science Foundation, the National Geographic Society, the David B. Jones Foundation, the Petrified Forest Museum Association, and the Friends of Petrified Forest National Park
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Extinction
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February 26, 2019
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https://www.sciencedaily.com/releases/2019/02/190226112310.htm
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Recovering forests important to conservation
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Tropical forests recovering from disturbance could be much more important to the conservation of forest bird species than first thought, according to a new study.
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The research, led by the University of Stirling, indicates that species extinctions caused by the destruction and degradation of tropical primary forests could be avoided if sufficient areas of secondary forest -- those regenerating following logging or clearance -- can be conserved.The findings -- published in Dr Rebekah Mayhew, an ecologist from the Faculty of Natural Sciences at Stirling, led the research, which involved colleagues from Imperial College London and the Smithsonian Tropical Research Institute in Panama. She said: "Despite many questioning the conservation value of secondary forests, we showed that they can be enormously valuable for birds when they are adjacent to extensive primary forests."After only two decades of growth, secondary forests connected to extensive primary forest can host diverse bird communities. Importantly, the overall pattern was similar with forest specialist birds. These birds are restricted to high-quality forest habitat, and are often used as an indicator of forest conservation value."The capacity of secondary forests to increase populations of these species has positive benefits for a range of ecosystem services that help humans, such as predation of invertebrate pests and dispersal of plant seeds."Over half of tropical forests are categorised as secondary. However, when compared to primary forests, young secondary forests are typically dismissed as having low conservation potential.Dr Mayhew and the team carried out research across 14 permanent forest survey plots in the Barro Colorado Nature Monument, close to the Panama Canal in Central America. The network is the most extensive chronosequence in the tropics, with plots aged between 20 and 120 years old. The scientists compared bird diversity in primary and secondary forests in the region, with almost 14,000 birds detected over a three-year period.Significantly, the team found that the benefits of secondary forests are strongly dependent on landscape context. Habitats isolated by inhospitable surroundings -- such as forests isolated on islands -- lack sufficient area to support viable populations of some rarer species, which tend to disappear over time.In contrast, secondary forests can substantially boost populations of species surviving in adjacent primary forests, such as Soberania National Park, the main block of primary forest surveyed by the researchers. This effect may be due to increased abundance and availability of insects and fruits in some younger forests, which provide valuable foraging grounds for forest birds if connected to intact primary forest.In other words, a smaller patch of old secondary forest (120 years old), isolated on an island, is not as beneficial to birds as a younger secondary forest (20 years old), located on the mainland and connected to extensive primary forest.Dr Mayhew said: "Secondary forests are rarely protected, but our research provides a strong argument for their conservation potential."Our findings emphasise the importance of reforesting and maintaining existing secondary forest, particularly at the borders of extensive tropical forest, and highlight the need for improved protection of secondary forest in protected area buffer zones throughout the tropics."
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Extinction
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February 25, 2019
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https://www.sciencedaily.com/releases/2019/02/190225105114.htm
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Skulls of 2 species of ancient reptile reconstructed
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Using two partially fragmented fossil skulls, a student at the University of Bristol has digitally reconstructed, in three-dimensions, the skulls of two species of ancient reptile that lived in the Late Triassic, one of which had been previously known only from its jaws.
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The research was completed by Sofia Chambi-Trowell, an undergraduate in Bristol's School of Earth Sciences, as part of her final-year project for her degree in Palaeobiology.Since then, similar beasts have been found elsewhere around Bristol and in South Wales, as well as in China and North America. In her project, Sofia worked on new fossils of She used CT scans of both skulls to reconstruct their original appearance, and she found evidence that the two species, which lived at the same time in the Late Triassic, some 205 million years ago, showed significant differences.Sofia said: "I found that "Other differences include the number, shape and size of the teeth in the jaws, suggesting the two species fed on different food."Professor Mike Benton, one of Sofia's project supervisors, added: "Sofia's work is a great example of how modern technology like CT scanning can open up information we would not know about."It took a lot of work, but Sofia has uncovered a good explanation of how many species of Her other supervisor, Dr David Whiteside, said: "Two hundred million years ago, Bristol lay much further south than it does today -- about the same latitude as Morocco."Also, sea level was higher, so the peaks of limestone hills south of Bristol and in South Wales were islands, like Florida today."They were full of dinosaurs, early mammals, and rhynchocephalians feeding on the rich, tropical plants and insects. Sofia's work helps us understand so much about this extraordinary time when dinosaurs were just taking over the world."
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Extinction
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February 22, 2019
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https://www.sciencedaily.com/releases/2019/02/190222101321.htm
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Proximity to land determines how coral reef communities respond to climate change events
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Severe weather and environmental disturbances, such as cyclones or thermal coral bleaching, affect specific areas of coral reefs differently, new research has shown.
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A new international study has found that the marine wildlife that live amongst the coral are affected differently by devastating climate change events, depending on how close to the mainland they are found.The research, co-authored by Laura Richardson from the University of Exeter, studied the effect of the natural disasters on the Great Barrier Reef (GBR) -- which is home to more than 1,500 species of fish including clownfish, parrotfish and lionfish.The research studied three specific areas of the GBR -- the inner reefs closest to the mainland, middle-shelf reefs, and outer-shelf reefs, where the continental shelf drops off into the Coral Sea. Surveys of fish and coral reef habitat were made both five years before and six months after two severe cyclones and a mass coral bleaching event.While those environmental events caused substantial and widespread loss of coral across all reefs, the numbers of herbivorous fishes remained stable (inner-shelf reefs) or even increased (middle- and outer-shelf reefs).Dr Richardson, a marine biologist at the University of Exeter's Penryn Campus said: "After widespread loss of corals due to large storms or severe coral bleaching events, herbivorous reef fish are vital for removing seaweed that starts to grow over the dead corals, so that new corals can grow, and surviving corals can recover."Understanding how these herbivorous fish respond across the continental shelf highlights where reefs may be more vulnerable and possibly slower to recover."The increased number of herbivorous fish on some reefs in this study is highly promising as they can help prevent the proliferation of seaweed after these huge disturbances."Importantly, however, the study showed that the number of herbivorous fish species decreased following the environmental events."The loss of species is of greatest concern, affecting the functioning of these reefs and their capacity to respond to future disturbances. It may be setting these reefs up for future ecological surprises" said Dr Hoey from James Cook University in Australia.The researchers believe the study -- the first of its kind -- offers a pivotal insight to allow for better conservation and management of coral reefs found worldwide, particularly those reefs exposed to land-based sources of pollution and sedimentation.The lead-author of the study, Eva McClure from James Cook University, said: "On coral reefs, it is common to find distinct communities of coral and reef fish living together at different locations across the continental shelf."But until now, we haven't known whether these different communities respond in the same way to environmental disturbances or whether specific local conditions might result in different community responses whether close to the mainland or further from shore."Coral reefs are made up of thin layers of calcium carbonate (limestone) secreted over thousands of years by billions of tiny soft bodied animals called coral polyps. They are amongst the world's most diverse marine ecosystems and are home to thousands of species of plants and animals.The Great Barrier Reef is the world's largest coral reef, stretching along the northeast coast of Australia, from the northern tip of Queensland, to just north of Bundaberg. However, the biggest differences in coral and fish communities tend to occur from east to west across the Great Barrier Reef.For the study, conducted by the University of Exeter and James Cook University in Australia, the researchers looked at coral reefs in three distinct positions across the breadth of the continental shelf to compare how the marine life and habitat were affected by the loss of coral following severe environmental disturbances.While each region was impacted by the disturbances, the research showed that the number of seaweed-eating fish increased on the middle and outer shelf areas, but not in the areas closest to the coast.The researchers believe that the study not only offers a unique insight into how the reefs are impacted by severe environmental conditions, but also the potential for recovery shown by each specific region.
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Extinction
| 2,019 |
February 22, 2019
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https://www.sciencedaily.com/releases/2019/02/190222101336.htm
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World's biggest bee found
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An international team of scientists and conservationists has announced the finding of what many consider to be the 'holy grail' of bee discoveries -- Wallace's giant bee.
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The bee (In January, a search team that set out to find and photograph Wallace's giant bee successfully rediscovered the species in the North Moluccas, an island group in Indonesia. The find resurrects hope that more of the region's forests still harbour this very rare species.The discovery was announced today.A member of the team, Honorary Professor Simon Robson from the School of Life and Environmental Sciences at the University of Sydney, said: "Amid such a well-documented global decline in insect diversity it's wonderful to discover that this iconic species is still hanging on."Dr Robson and Dr Glen Chilton, an honorary professor at Saint Mary's University in Canada, joined with Eli Wyman from Princeton University and Clay Bolt, a conservation photographer from Montana, to successfully rediscover this bee. The team was supported by Global Wildlife Conservation, an Austin, Texas, based organisation that runs a Search for Lost Species program."It was absolutely breathtaking to see this 'flying bulldog' of an insect that we weren't sure existed anymore," said Clay Bolt, a natural history photographer specialising in bees, who took the first photos and video of the species alive after spending years researching the right habitat with collaborator and team member, Eli Wyman from Princeton University."To see how beautiful and big the species is in real life, to hear the sound of its giant wings thrumming as it flew past my head, was just incredible. My dream is to now use this rediscovery to elevate this bee to a symbol of conservation in this part of Indonesia."The female giant bee makes her nest in active arboreal termite mounds, using her large mandibles to collect sticky tree resin to line the nest and protect it from invading termites. In hot and humid conditions, and sometimes during torrential downpours, the team observed dozens of termite mounds over the course of the search.It wasn't until the last day of a five-day stop in an area of interest that the team found a single female Wallace's giant bee living in an arboreal termites' nest in a tree about 2.5 metres off the ground.The bee is named after Alfred Russel Wallace, the co-discoverer alongside Charles Darwin of the theory of evolution through natural selection. Wallace, a British entomologist, discovered the giant bee exploring the Indonesian island of Bacan. He described the female bee, which is about the length a human thumb, as "a large black wasp-like insect, with immense jaws like a stag-beetle."The bee wasn't seen again until 1981, when entomologist Adam Messer rediscovered it on three Indonesian islands and was able to observe some of its behaviour, including how it uses its mandibles to gather resin and wood for its nests. Since then, other teams have looked for the bee, with no luck."Messer's rediscovery gave us some insight, but we still know next to nothing about this extraordinary insect," said Mr Wyman. "I hope this rediscovery will spark research that will give us a deeper understanding of this unique bee and inform any future efforts to protect it from extinction."Although little is known about the bee, the species depends on primary lowland forest for resin and the nests of tree-dwelling termites, Mr Bolt said. In Indonesia, forest destruction for agriculture, however, threatens the habitat for this species and many others. Between 2001 and 2017, Indonesia lost 15 percent of its tree cover, according to Global Forest Watch.The team has already started conversations with Indonesian collaborators to look for Wallace's giant bee in other locations -- with the hope of eventually working together to develop a plan to strengthen conservation measures for the bee.A documentary film, In Search of the Giant Bee is now being produced by Vanessa Dylyn of Matter of Fact Media, in association with Glen Chilton.Video: https://www.youtube.com/watch?time_continue=5&v=JT_B6sSuF5I
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Extinction
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February 21, 2019
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https://www.sciencedaily.com/releases/2019/02/190221141511.htm
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Do volcanoes or an asteroid deserve blame for dinosaur extinction?
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Based on new data published today in the journal
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But it leaves unclear to what degree the two catastrophes contributed to the near-simultaneous mass extinction that killed off the dinosaurs and many other forms of life.The research sheds light on huge lava flows that have erupted periodically over Earth's history, and how they have affected the atmosphere and altered the course of life on the planet.In the study, University of California, Berkeley, scientists report the most precise and accurate dates yet for the intense volcanic eruptions in India that coincided with the worldwide extinction at the end of the Cretaceous Period, the so-called K-Pg boundary. The million-year sequence of eruptions spewed lava flows for distances of at least 500 kilometers across the Indian continent, creating the so-called Deccan Traps flood basalts that in some places are nearly 2 kilometers thick."Now that we have dated Deccan Traps lava flows in more and different locations, we see that the transition seems to be the same everywhere. I would say, with pretty high confidence, that the eruptions occurred within 50,000 years, and maybe 30,000 years, of the impact, which means they were synchronous within the margin of error," said Paul Renne, a professor-in-residence of earth and planetary science at UC Berkeley, director of the Berkeley Geochronology Center and senior author of the study, which will appear online Feb. 21. "That is an important validation of the hypothesis that the impact renewed lava flows."The new dates also confirm earlier estimates that the lava flows continued for about a million years, but contain a surprise: three-quarters of the lava erupted after the impact. Previous studies suggested that about 80 percent of the lava erupted before the impact.If most of the Deccan Traps lava had erupted before the impact, then gases emitted during the eruptions could have been the cause of global warming within the last 400,000 years of the Cretaceous Period, during which temperatures increased, on average, about 8 degrees Celsius (14.4 degrees Fahrenheit). During this period of warming, species would have evolved suited to hothouse conditions, only to be confronted by global cooling from the dust or by climate cooling gases caused by either the impact or the volcanos.The cold would have been a shock from which most creatures would never have recovered, disappearing entirely from the fossil record: literally, a mass extinction.But if most of the Deccan Traps lava emerged after the impact, this scenario needs rethinking."This changes our perspective on the role of the Deccan Traps in the K-Pg extinction," said first author Courtney Sprain, a former UC Berkeley doctoral student who is now a postdoc at the University of Liverpool in the United Kingdom. "Either the Deccan eruptions did not play a role -- which we think unlikely -- or a lot of climate-modifying gases were erupted during the lowest volume pulse of the eruptions."The hypothesis that climate-altering volcanic gases leak out of underground magma chambers frequently, and not just during eruptions, is supported by evidence from present-day volcanos, such as those of the gas-spewing Mt. Etna in Italy and Popocatepetl in Mexico, the researchers said. Magma stewing below the surface is known to transmit gases to the atmosphere, even without eruptions."We are suggesting that it is very likely that a lot of the gases that come from magma systems precede eruptions; they don't necessarily correlate with eruptions," Renne said. In the case of the K-Pg extinction, the symptoms of significant climate change occurred before the peak in volcanic eruptions.Renne, Sprain and their colleagues are using a precise dating method, argon-argon dating, to determine when the impact occurred and when the Deccan Traps erupted to clarify the sequence of catastrophes at the end of the Cretaceous Period and beginning of the Tertiary Period -- the K-Pg boundary, formerly referred to as the K-T boundary.In 2013, using rocks from Montana, they obtained the most precise date yet for the impact, and in 2018, they updated that to 66,052,000 years ago, give or take 8,000 years. Then, in 2015, they determined from a handful of samples in India that, in at least one spot, the peak of the Deccan Traps eruptions occurred within about 50,000 years of that date, which means, in geologic time, that the incidents were basically simultaneous.Now, with three times more rock samples from areas covering more of the Deccan Traps, the researchers have established that the time of peak eruptions was the same across much of the Indian continent. This supports the group's hypothesis that the asteroid impact triggered super-earthquakes that caused a strong burst of volcanism in India, which is almost directly opposite the impact site, the Chicxulub crater in the Caribbean Sea.Sprain and Renne argue that the coincident catastrophes likely delivered a one-two punch to life on Earth, but the details are unclear. Volcanic eruptions produce lots of gases, but some, like carbon dioxide and methane, warm the planet, while others, like sulfur aerosols, are cooling. The impact itself would have sent dust into the atmosphere that blocked sunlight and cooled the Earth, though no one knows for how long."Both the impact and Deccan volcanism can produce similar environmental effects, but these are occurring on vastly differing timescales," Sprain said. "Therefore, to understand how each agent contributed to the extinction event, assessing timing is key."Which gases in the Deccan Traps are emitted when is a question that's hard to answer, because there are no flood basalt eruptions going on today, despite numerous ones in Earth's history. The most recent, near the Columbia River in the Pacific Northwest, dwindled 15 million years ago after 400,000 years of eruptions.The paucity of information about flood basalts is one reason Renne and Sprain are interested in the Deccan Traps, which are still young enough to contain information about the sequence, effects and scale of the eruptions, and perhaps the cause."It makes we wonder whether we may see some external forcing mechanism, like the impact for the Deccan Traps, for other flood basalts that lead up to major peaks in eruptions, like the Columbia River basalts or the Siberian Traps," Renne said. "Could a major earthquake in nearby subduction zones or the accumulation of pressure due to rising magma unleash these major episodes in flood basalts?"Sprain noted that, in the same issue of
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February 21, 2019
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https://www.sciencedaily.com/releases/2019/02/190221095038.htm
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New species of tiny tyrannosaur foreshadows rise of T. rex
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A newly discovered, diminutive -- by
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Meet "With a lethal combination of bone-crunching bite forces, stereoscopic vision, rapid growth rates, and colossal size, tyrant dinosaurs reigned uncontested for 15 million years leading up to the end-Cretaceous extinction -- but it wasn't always that way," says Lindsay Zanno, paleontologist at North Carolina State University, head of paleontology at the North Carolina Museum of Sciences and lead author of a paper describing the research. "Early in their evolution, tyrannosaurs hunted in the shadows of archaic lineages such as allosaurs that were already established at the top of the food chain."Medium-sized, primitive tyrannosaurs have been found in North America dating from the Jurassic (around 150 million years ago). By the Cretaceous -- around 81 million years ago -- North American tyrannosaurs had become the enormous, iconic apex predators we know and love. The fossil record between these time periods has been a blank slate, preventing scientists from piecing together the story behind the ascent of tyrannosaurs in North America. "When and how quickly tyrannosaurs went from wallflower to prom king has been vexing paleontologists for a long time," says Zanno. "The only way to attack this problem was to get out there and find more data on these rare animals."That's exactly what Zanno and her team did. A decade spent hunting for dinosaur remains within rocks deposited at the dawn of the Late Cretaceous finally yielded teeth and a hind limb from the new tyrannosaur. In fact, the lower leg bones of But don't let the size fool you. ""Although the earliest Cretaceous tyrannosaurs were small, their predatory specializations meant that they were primed to take advantage of new opportunities when warming temperatures, rising sea-level and shrinking ranges restructured ecosystems at the beginning of the Late Cretaceous," Zanno says. "We now know it took them less than 15 million years to rise to power."The bones of The research appears in
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February 21, 2019
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https://www.sciencedaily.com/releases/2019/02/190221110425.htm
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How coral bleaching threatens Caribbean communities
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Climate change has fueled coral reef bleaching throughout the tropics, with negative consequences for reef ecosystems and the people who depend on them. A new study finds that in the Caribbean, independent island nations such as Cuba and Jamaica are less vulnerable to coral bleaching than island territories like Saint Barthélemy.
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The study, published today in the Coral bleaching -- which occurs when coral expels the algae living within their tissues -- is often caused by unusually warm ocean temperatures. Corals are the cornerstones of reef ecosystems. If a bleaching event is prolonged and causes enough corals to die, the entire reef ecosystem can become severely compromised. Coral bleaching can have ripple effects for coastal communities that depend on reef ecosystems for benefits such as seafood, tourism, and shoreline protection."This study brings together data on 35 biophysical, ecological, socioeconomic, and management variables from 30 islands and creates important advances in understanding climate change vulnerability in the Caribbean," said Siegel, a PhD candidate in the Department of Environmental Science, Policy, and Management.The study's interdisciplinary team, with co-authors from Florida State University, UC Santa Barbara, and the University of Vigo, focused on the Caribbean island chain that runs from the Bahamas in the north to Trinidad & Tobago in the south, a region with high socioeconomic diversity, including important differences in economic dependence on reefs.Following a framework developed by the Intergovernmental Panel on Climate Change, the team divided vulnerability into three separate components: exposure (the likelihood of bleaching events), sensitivity (the effect that bleaching is likely to have on the ecosystem and people), and the ability of the ecosystem and people to adapt to or recover from a bleaching event. Siegel and her collaborators used more than 250 published datasets, survey results, and government reports to assemble indicators for these components on each island, revealing important patterns in vulnerability across the region."We were surprised to find that independent islands have lower social-ecological vulnerability than territories," said Siegel. "Territories -- such as the Dutch islands of Sint Maarten and Saba -- tend to be left out of global assessments of climate change vulnerability, but our results suggest that they need to invest in improving their ability to adapt to environmental changes."The study found that while independent islands are more exposed to environmental conditions that can trigger bleaching events, they are less likely to experience negative socioeconomic consequences because they are less economically dependent on reefs and are better equipped to detect and adapt to environmental changes. In contrast, the French territory Saint Barthélemy has very low exposure but experiences high overall vulnerability due to socioeconomic factors such as an economic dependence on reef tourism."Bleaching events have become more common and severe in recent decades, a trend that may only worsen as the world's oceans continue to warm." says study co-author Sarah Lester, an assistant professor of geography at Florida State University. "It's essential that we develop a better understanding of how this disturbance impacts coral reef ecosystems and the people that rely on these ecosystems for their livelihood."The study's findings can help decision-makers and resource managers take actions to reduce the negative impacts of bleaching at the island level. Depending on the causes of an island's vulnerability, actions could include implementing fishing regulations to protect species that play key roles in reef recovery, enacting land use policies and farming practices to improve the water quality on reefs, establishing environmental monitoring programs, and promoting economic diversification.
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February 18, 2019
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https://www.sciencedaily.com/releases/2019/02/190218123129.htm
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Biodiversity on land is not higher today than in the past, study shows
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The rich levels of biodiversity on land seen across the globe today are not a recent phenomenon: diversity on land has been similar for at least the last 60 million years, since soon after the extinction of the dinosaurs.
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According to a new study led by researchers at the University of Birmingham and involving an international team of collaborators, the number of species within ecological communities on land has increased only sporadically through geological time, with rapid increases in diversity being followed by plateaus lasting tens of millions of years.Previously, many scientists have argued that diversity increased steadily through geological time, which would mean that biodiversity today is much greater than it was tens of millions of years ago. But building an accurate picture of how land diversity was assembled is challenging because the fossil record generally becomes less complete further back in time. By using modern computing techniques, capable of analysing hundreds of thousands of fossils, patterns are starting to emerge that challenge this view.The researchers, from the University of Birmingham's School of Geography, Earth and Environmental Sciences and other institutions in the UK, USA and Australia, were able to study fossil data collected by palaeontologists over the past 200 years at around 30,000 different fossil sites around the globe. The team focused on data from land vertebrates dating back to the very earliest appearance of this group nearly 400 million years ago.They found that the average number of species within ecological communities of land vertebrates have not increased for tens of millions of years. Their results, published in Lead researcher, Dr Roger Close, says: "Scientists often think that species diversity has been increasing unchecked over millions of years, and that diversity is much greater today than it was in the distant past. Our research shows that numbers of species within terrestrial communities are limited over long timescales, which contradicts the results of many experiments in modern ecological communities -- now we need to understand why."One reason why diversity within ecological communities does not increase unchecked on long timescales could be because resources used by species, such as food and space, are finite. Competition for these resources may prevent new species invading ecosystems and lead to a balance between rates of speciation and extinction. After the origins of major groups of animals, or large-scale ecological disruptions like mass extinctions, though, increases in diversity may happen abruptly -- on geological, if not human timescales -- and are again followed by long periods where no increases occur.He adds: "Contrary to what you might expect, the largest increase in diversity within land vertebrate communities came after the mass extinction that wiped out the dinosaurs, 66 million years ago, at the end of the Cretaceous period. Within just a few million years, local diversity had increased to two or three times that of pre-extinction levels -- driven primarily by the spectacular success of modern mammals."Professor Richard Butler, who was also part of the research team, said "Our work provides an example of the combined power of the fossil record and modern statistical approaches to answer major questions about the origins of modern biodiversity. By understanding how biodiversity has changed in the past, we may be able to better understand the likely long-term impact of the current biodiversity crisis."Funded by the European Research Council through the European Union's Horizon 2020 research and innovation programme, the research was led by the University of Birmingham, and also involved researchers from the University of Oxford, Macquarie University, the Smithsonian Institute, the University of Bath, the Natural History Museum, London, Imperial College London, and George Mason University.
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February 15, 2019
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https://www.sciencedaily.com/releases/2019/02/190215135832.htm
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New study looks at ways to cut roadkill numbers for small and medium-sized mammals
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Most motorists pay little attention to the amount of roadkill they drive over or past on the highway, except when swerving to avoid it.
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But odds are the number of dead animals they encounter is far higher than they think. And it will likely rise globally due to increasing road construction and traffic volumes if humans don't install measures to prevent woodland animals from wandering onto busy roads in the first place.Jochen Jaeger is an associate professor in the Department of Geography, Planning and Environment at Concordia. He recently oversaw a study that measured the effectiveness of underground passageways that would let fauna cross the highway safely, and if road mortality levels are lower in road sections with fences and wildlife passages in place than in road sections where no such safety measures exist.The paper, published in the The expanded highway presented a risky landscape for the wildlife living alongside and travelling over it. In order to mitigate animal mortality and the barrier effect of the road, the ministry built 33 wildlife underpasses over a 68-km section. Alongside each underpass opening were 200-metre-long fences.The hope was that the underpasses, coupled with the fences, would induce small and medium-sized animals to cross underneath the highway rather than over it. Other jurisdictions have used fences and underpasses for this group of animals, but Jaeger says the Highway 175 project was basically the first to use them in Quebec, which he thinks is a laudable step in the right direction.To find out how effective these fences and underpasses were in preventing the deaths of small and medium-sized animals, Jaeger's team of students had to first see how many carcasses they would count on the road.Over the course of four summers, from 2012 to 2015, they would drive nearly daily along the 68-km stretch of highway (in both directions) and count the number of dead animals they saw. They found a lot, Jaeger says, especially porcupines, but also raccoons, red foxes, skunks, snowshoe hares, squirrels, woodchucks, a few beavers, even two lynx, and many more small mammals like mice and shrews.They counted close to 900 bodies in all, though Jaeger believes the actual number of dead animals is significantly higher.To find out how many animals go undetected, Plante estimated detection probability by comparing the results of two search teams that worked the road independently for several months. She found that the spotter teams counted only 82 per cent of medium-sized animals. For smaller critters, the detection probability was much lower. The data showed that the observers counted only 17 per cent of the total small mammals dead. In addition, an unknown number of injured animals are thought to have wandered off the highway to die along the side of the road.According to Plante, the study's lead author who now works for a Montreal-based environmental consulting firm, "Most people don't notice how much roadkill there is on the road. My eyes are so used to counting them now that I can spot bodies easily. Most drivers miss so much they don't realize how big the problem is."But as striking as those numbers were, Jaeger says he was even more interested in where the bodies were found."We looked at road mortality within the sections that were completely fenced, those that were in the vicinity of the fence ends and those that were far away from the fences," he explains."We found that road mortality was highest at the fence ends, which indicates that some of the animals walked away from the underpass and along the fence to look for an opening. When they found one at the end of the fence, they would attempt to cross the highway and some of them would be killed. This indicates that the fences would need to be longer to discourage animals from moving along them and to meet the target of reduced road mortality."Plante says that another possible factor affecting the choices of animals in where to make an attempt to cross is the vegetation growing between the roads, which gives animals an illusion of safety. They will run the risk of crossing the first two busy lanes of road to reach the green patches only to find themselves in the same predicament of having to cross another two lanes.Jaeger notes that this is not the first study to look at the effect exclusion fences have on the road mortality of mammals. It is, however, the first to look at the "fence-end" effect for medium-sized mammals and smaller."Transport ministries mainly care about larger animals like moose and bears because they cause accidents, while small and medium-sized animals usually don't, unless a driver swerves to avoid them," he says.Animals are going to cross highways one way or another, Jaeger adds. It is in their nature to move across the landscape in search for food, for a mate or for a new territory. The responsibility for humans is to reduce the impacts of roads and traffic on wildlife populations by making those crossings safer. So many porcupines have been killed along the new Highway 175, for instance, that he fears the population in the proximity of the highway could be permanently affected. Porcupines have a very low reproductive rate, much lower than other mammal species of this size: A couple has only one offspring -- called a porcupette -- per year.In order to ensure stable and healthy wildlife populations, future highway designers should integrate measures like fences with underpasses, and sometimes overpasses as well. The identification of roadkill hotspots can help determine where to put the fences and wildlife passages most effectively."Having connections across or under a highway is important, but we first and more urgently should think about ways to reduce the numbers of animals getting killed on the road," Jaeger says. The number of roads on the planet is rapidly increasing. Quite a few of the new roads will affect biodiversity hotspots.With the incipient sixth mass extinction event caused by human activities under way, the task of proper road mitigation is crucial in order to preserve biodiversity, and particularly so in the remaining biodiversity hotspots. The results of the study can help improve the design and placement of mitigation measures and therefore are relevant far beyond Quebec.The study was supported by the Ministère des transports, de la mobilité durable et de l'électrification des transports du Québec, recently renamed to the Ministère des transports du Québec, and the Quebec Centre for Biodiversity Science.
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February 13, 2019
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https://www.sciencedaily.com/releases/2019/02/190213142720.htm
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New dinosaur with heart-shaped tail provides evolutionary clues for African continent
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A new dinosaur that wears its "heart" on its tail provides new clues to how ecosystems evolved on the African continent during the Cretaceous period according to researchers at Ohio University.
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The OHIO team identified and named the new species of dinosaur in an article published this week in The new dinosaur is named The initial discovery of Titanosaurs are best known from Cretaceous-age rocks in South America, but other efforts by the team include new species discovered in Tanzania, Egypt, and other parts of the African continent that reveal a more complex picture of dinosaurian evolution on the planet. "The discovery of dinosaurs like The excavation process spanned multiple years, and included field teams suspended by ropes and large-scale mechanical excavators to recover one of the more complete specimens from this part of the sauropod dinosaur family tree. "Without the dedication of several field teams, including some whose members donned climbing gear for the early excavations, the skeleton would have eroded away into the river during quite intense wet seasons in this part of the East African Rift System," added O'Connor."This latest discovery is yet another fine example of how Ohio University researchers work the world over in their pursuit of scientific research," Ohio University President M. Duane Nellis said. "This team has turned out a number of notable discoveries which collectively contribute significantly to our understanding of the natural world.""This new dinosaur gives us important information about African fauna during a time of evolutionary change," said Judy Skog, a program director in the National Science Foundation's Division of Earth Sciences, which funded the research. "The discovery offers insights into paleogeography during the Cretaceous. It's also timely information about an animal with heart-shaped tail bones during this week of Valentine's Day."Recent findings by the research team in the Rukwa Rift Basin include:· · · Early evidence for monkey-ape split, Rukwa Rift Basin Project· Early evidence of insect farming -- Fossil Termite Nests, Rukwa Rift Basin"The Tanzanian story is far from over but we know enough to start asking what paleontological and geological similarities and dissimilarities there are with nearby rock units. Revisiting Malawi is my top priority to address these broader, regional questions," said Gorscak, who also participates in ongoing projects in Egypt and Kenya. "With
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Extinction
| 2,019 |
February 13, 2019
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https://www.sciencedaily.com/releases/2019/02/190213142718.htm
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Scientists look to past to help identify fish threatened with local extinction
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Marine scientists from the University of Queensland, WCS (Wildlife Conservation Society) and other groups have developed a methodology to assess fish stocks that combines new data with archeological and historical records -- some dating back to the 8th Century AD. In a study conducted in along the coast of Kenya, the researchers reconstructed species' occurrences by combining modern underwater transect surveys and catch assessments with historical records that included observations from 18th century naturalists and data from archaeological sites including ancient middens dating back more than a thousand years.
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Their analysis provided a more accurate assessment, finding that some species previously thought to be "Least Concern," "Unevaluated," or "Data Deficient" on the IUCN's Red List of Threatened Species were actually threatened with local extinction. These included species of groupers, trevallies, rubberlips, and other fish. Further, the historical data identified species that were previously exploited in the region and most likely locally extinct.The authors say their new method is inexpensive and could be important in filling in knowledge gaps in species extinction assessments.
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Extinction
| 2,019 |
February 13, 2019
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https://www.sciencedaily.com/releases/2019/02/190213081637.htm
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Giant 'megalodon' shark extinct earlier than previously thought
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Megalodon -- a giant predatory shark that has inspired numerous documentaries, books and blockbuster movies -- likely went extinct at least one million years earlier than previously thought, according to new research published Feb. 13 in
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Earlier research, which used a worldwide sample of fossils, suggested that the 50-foot-long, giant shark However, a team of researchers led by vertebrate paleontologist Robert Boessenecker with the College of Charleston, Charleston, South Carolina, noted that in many places there were problems with the data regarding individual fossils in the study estimating the extinction date.In the new study, the researchers reported every fossil occurrence of Besides Boessenecker, the research team included Dana Ehret, of New Jersey State Museum; Douglas Long, of the California Academy of Sciences; Morgan Churchill, of the University of Wisconsin Oshkosh; Evan Martin, of the San Diego Natural History Museum; and Sarah Boessenecker, of the University of Leicester, United Kingdom.They found that genuine fossil occurrences were present until the end of the early Pliocene epoch, 3.6 million years ago. All later fossils either had poor data provenance and likely came from other fossil sites or showed evidence of being eroded from older deposits. Until 3.6 million years ago, "We used the same worldwide dataset as earlier researchers but thoroughly vetted every fossil occurrence, and found that most of the dates had several problems-fossils with dates too young or imprecise, fossils that have been misidentified, or old dates that have since been refined by improvements in geology; and we now know the specimens are much younger," Boessenecker said."After making extensive adjustments to this worldwide sample and statistically re-analyzing the data, we found that the extinction of This is a substantial adjustment as it means that "The extinction of It also is further unclear if this proposed mass extinction is actually an extinction, as marine mammal fossils between 1 and 2 million years old are extraordinarily rare-giving a two-million- year-long period of "wiggle room.""Rather, it is possible that there was a period of faunal turnover (many species becoming extinct and many new species appearing) rather than a true immediate and catastrophic extinction caused by an astronomical cataclysm like a supernova," Boessenecker said.The researchers speculate that competition with the newly evolved modern great white shark (Great whites first show up with serrated teeth about 6 million years ago and only in the Pacific; by 4 million years ago, they are finally found worldwide."We propose that this short overlap (3.6-4 million years ago) was sufficient time for great white sharks to spread worldwide and outcompete
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| 2,019 |
February 11, 2019
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https://www.sciencedaily.com/releases/2019/02/190211163959.htm
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Mosquitoes that carry malaria may have been doing so 100 million years ago
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The anopheline mosquitoes that carry malaria were present 100 million years ago, new research shows, potentially shedding fresh light on the history of a disease that continues to kill more than 400,000 people annually.
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"Mosquitoes could have been vectoring malaria at that time, but it's still an open question," said the study's corresponding author, George Poinar Jr. of Oregon State University's College of Science. "Back then anopheline mosquitoes were probably biting birds, small mammals and reptiles since they still feed on those groups today."In amber from Myanmar that dates to the mid-Cretaceous Period, Poinar and co-authors described a new genus and species of mosquito, which was named "This discovery provides evidence that anophelines were radiating -- diversifying from ancestral species -- on the ancient megacontinent of Gondwana because it is now thought that Myanmar amber fossils originated on Gondwana," said Poinar, an international expert in using plant and animal life forms preserved in amber to learn more about the biology and ecology of the distant past.Findings were published in Most malaria, especially the species that infect humans and other primates, is caused primarily by one genus of protozoa, In a previous work, he suggested that the origins of malaria, which today can infect animals ranging from humans and other mammals to birds and reptiles, may have first appeared in an insect such as a biting midge that was found to be vectoring a type of malaria some 100 million years ago. Now he can include mosquitoes as possible malaria vectors that existed at the same time.In a 2007 book, "What Bugged the Dinosaurs? Insects, Disease and Death in the Cretaceous," Poinar and his wife, Roberta, showed insect vectors from the Cretaceous with pathogens that could have contributed to the widespread extinction of the dinosaurs some 65 million years ago."There were catastrophic events that happened around that time, such as asteroid impacts, climatic changes and lava flows," the Poinars' wrote. "But it's still clear that dinosaurs declined and slowly became extinct over thousands of years, which suggests other issues must also have been at work. Insects, microbial pathogens such as malaria, and other vertebrate diseases were just emerging around that time."Scientists have long debated about how and when malaria evolved, said Poinar, who was the first to discover malaria in a 15- to 20-million-year-old fossil mosquito from the New World, in what is now the Dominican Republic.It was the first fossil record of Understanding the ancient history of malaria, Poinar said, might offer clues on how its modern-day life cycle evolved and how to interrupt its transmission. Since the sexual reproductive stage of malaria only occurs in the insect vectors, Poinar considers the vectors to be the primary hosts of the malarial pathogen, rather than the vertebrates they infect.The first human recording of malaria was in China in 2,700 B.C., and some researchers say it may have resulted in the fall of the Roman Empire. In 2017 there were 219 million cases of malaria worldwide, according to the World Health Organization. Immunity rarely occurs naturally and the search for a vaccine has not yet been successful.
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Extinction
| 2,019 |
February 7, 2019
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https://www.sciencedaily.com/releases/2019/02/190207142237.htm
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Bee dispersal ability may influence conservation measures
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The abilities of various bee species to disperse influences the pattern of their population's genetic structure, which, in turn, can constrain how they respond to environmental change, as reported by an international team of researchers.
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"Bees are declining around the world, which is a problem because these pollinators are critically important, both ecologically and economically," said Margarita López-Uribe, assistant professor of entomology, Penn State. "Our study has major implications for bee species conservation. For example, the ability of a species to disperse farther can enable that species to move to suitable areas under scenarios of climate change."The team reviewed all pre-existing studies that had measured bee population genetic structure. The researchers related this population genetic structure to the bees' body size with a goal of determining whether this relationship would provide an indication of how susceptible bees are to barriers to their movement, such as the destruction of habitat due to deforestation or urbanization.The team's results appeare online in February in According to López-Uribe, population genetic structure describes patterns of genetic diversity -- the basis of a population's ability to evolve and adapt to new conditions -- among populations within a species. Lower population genetic structure suggests that the genetic diversity of a species is equally distributed across its geographic range, and higher population genetic structure suggests that the genetic diversity is clustered or subdivided into groups.In addition to body size, López-Uribe and her colleagues also examined the breadth of the bees' diets and their social behavior -- whether they are solitary species or work and live together as part of a group. The team focused on studies that used microsatellite molecular markers -- unique bits of DNA that are prone to mutations and allow scientists to quantify genetic diversity in a species and examine the pattern of that species' population genetic structure.The scientists found that bee species with larger body sizes and social behaviors exhibit patterns of lower population genetic structure than bees with smaller bodies and solitary behaviors. The team did not find diet specialization to influence the population genetic structure of bees."Dispersal is hard to study in small insects," said López-Uribe. "Our study is the first to link bee body size and sociality with population genetic structure, which means we can predict which species may be at risk of local extinction based on these traits."Antonella Soro, research assistant, Martin-Luther University of Halle-Wittenberg, Germany, noted that the study also has important implications for future research."It confirms body size as a master trait whose variation and genetic basis should be the focus of further inquiry if we want to understand how bees adapt to a rapidly changing environment," said Soro.Other authors on the paper include Shalene Jha, associate professor, University of Texas at Austin.The Army Research Office and the National Science Foundation supported this research.
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Extinction
| 2,019 |
February 7, 2019
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https://www.sciencedaily.com/releases/2019/02/190207115003.htm
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Earliest known seed-eating perching bird discovered in Fossil Lake, Wyoming
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Most of the birds you've ever seen -- sparrows, finches, robins, crows -- have one crucial thing in common: they're all what scientists refer to as perching birds, or "passerines." The passerines make up about 6,500 of the 10,000 bird species alive today. But while they're everywhere now, they were once rare, and scientists are still learning about their origins. In a new paper in Current Biology, researchers have announced the discovery of one of the earliest known passerine birds, from 52 million years ago.
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"This is one of the earliest known perching birds. It's fascinating because passerines today make up most of all bird species, but they were extremely rare back then. This particular piece is just exquisite," says Field Museum Neguanee Distinguished Service Curator Lance Grande, an author of the paper. "It is a complete skeleton with the feathers still attached, which is extremely rare in the fossil record of birds."The paper describes two new fossil bird species -- one from Germany that lived 47 million years ago, and another that lived in what's now Wyoming 52 million years ago, a period known as the Early Eocene. The Wyoming bird, The fossil birds' finch-like, thick beaks hint at their diet. "These bills are particularly well-suited for consuming small, hard seeds," says Daniel Ksepka, the paper's lead author, curator at the Bruce Museum in Connecticut. Anyone with a birdfeeder knows that lots of birds are nuts for seeds, but seed-eating is a fairly recent biological phenomenon. "The earliest birds probably ate insects and fish, some may have been eating small lizards," says Grande. "Until this discovery, we did not know much about the ecology of early passerines. "We were able to show that a comparable diversity of bill types already developed in the Eocene in very early ancestors of passerines," says co-author Gerald Mayr of the Senckenberg Research Institute in Frankfurt. "The great distance between the two fossil sites implies that these birds were widespread during the Eocene, while the scarcity of known fossils suggests a rather low number of individuals," adds Ksepka.While passerine birds were rare 52 million years ago, "Fossil Lake is a really graphic picture of an entire community locked in stone -- it has everything from fishes and crocs to insects, pollen, reptiles, birds, and early mammals," says Grande. "We have spent so much time excavating this locality, that we have a record of even the very rare things."Grande notes that Fossil Lake provides a unique look at the ancient world -- one of the most detailed pictures of life on Earth after the extinction of the dinosaurs (minus the birds) 65 million years ago. "Knowing what happened in the past gives us a better understanding of the present and may help us figure out where we are going for the future."With that in mind, Grande plans to continue his exploration of the locale. "I've been going to Fossil Lake every year for the last 35 years, and finding this bird is one of the reasons I keep going back. It's so rich," says Grande. "We keep finding things that no one's ever seen before."
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Extinction
| 2,019 |
February 7, 2019
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https://www.sciencedaily.com/releases/2019/02/190207111303.htm
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New way to help increase conservation impact
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A study led by researchers at the University of Southampton reveals huge variations in the similarity and breadth of animal roles in nature across different parts of the world.
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The research, in partnership with Memorial University of Newfoundland, goes beyond just counting the types of animals there are and instead accounts for the differences between wildlife and their roles in the environment. This information is important to conservation efforts, as it enables the identification of places where there are only a few species performing a role, as opposed to regions where many species carry out similar rolesThe scientists combined multiple databases of information concentrating on six biologically important attributes of the roles animals play (traits). The selected traits included factors such as diet, daily activity and body size for 15,485 bird and mammal species. They were able to build a global picture of traits for different animals -- mapping which areas in the world had many overlapping roles and would therefore benefit from habitat conservation, as well as for those which had more unique, vulnerable ones and would benefit from species-focussed conservation.In the tropics, for example, the environment is teeming with life and many species exist which are very similar to each other. There may be numerous types of rodent, which perform similar functions in the environment, such as eating insects or helping to disperse seeds. The loss of one or two of these rodent species may not have too much impact though, as other types will simply compensate.However, taking Africa as an example, mammals which perform very specific functions may be more important, such as elephants -- eating hundreds of kilograms of vegetation a day, as well as churning the earth with their feet and tusks. The loss of elephants would likely have a much bigger impact because other animals aren't performing these kinds of specialist roles to the same degree.Interestingly, the study -- the first to examine both birds and mammals together in this way -- found many overlaps between these two groups, even when taking into account flight and daytime and nocturnal behaviour.Lead author Robert Cooke, from the University of Southampton, comments: "This is a new way of looking at how we can maximise effective conservation efforts and we hope that it will provide governments and relevant charities worldwide with the big picture on which areas are most at risk from losing the functionality of birds and mammals in the environment -- thus helping them to concentrate their efforts in the most effective directions."Professor of Applied Spatial Ecology Felix Eigenbrod, also of the University of Southampton, says: "This is an important study as it shows us how crucial it is to look at the diversity of life in different ways to really understand where to best focus precious conservation funding."The researchers hope more detailed work can be carried out in the future to look more closely at how species interact and effect each other. Findings for this latest study are published in the journal
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Extinction
| 2,019 |
February 6, 2019
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https://www.sciencedaily.com/releases/2019/02/190206144506.htm
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Species 'hotspots' created by immigrant influx or evolutionary speed depending on climate
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Some corners of the world teem with an extraordinary variety of life. Charles Darwin noted that: "The same spot will support more life if occupied by very diverse forms."
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The question of how these 'hotspots' of biodiversity -- from California to the Galapagos -- acquired such a wealth of species has long puzzled naturalists.Now, scientists at the University of Cambridge have conducted a 'big data' study of almost all the world's mammal and bird species to reveal the answer -- and it's very different depending on climate.According to the study, tropical hotspots close to the equator have generated new species at a much faster rate than their surrounding areas during the last 25 million years of evolution.However, biodiversity hotspots in more temperate northerly regions, such as the Mediterranean basin and Caucasus Mountains, are mainly populated with immigrant species that originated elsewhere.Scientists say these migrants may well have been escaping the effects of long-term "geological processes" such as vast encroaching glaciers. Warmer climes, as well as peninsulas and mountain ranges, could have offered shelter.The researchers argue that their new study, published today in the journal "We've known for decades that just a subset of places on Earth, no more than 20%, contain about half of all vertebrate species. However, we lacked the tools and data to understand why these patterns exist," said senior author Dr Andrew Tanentzap, from Cambridge's Department of Plant Sciences."Large-scale initiatives to map species across the planet and in the Tree of Life, as well as advances in computing, are expanding our understanding of evolution in exciting ways. This study can now provide an answer to the old question of why diversity varies so much across the world."Cambridge scientists used new computational techniques to combine several giant datasets. These included the global distribution of 11,093 bird species and 5,302 mammals, and detailed evolutionary trees that track the origin of thousands of organisms through deep time.In this way, the researchers were able to analyse the development of particularly species-rich areas within each of the Earth's great "biogeographical regions" -- from Australasia to the Nearctic.They found that biodiversity hotspots in the tropics, such as South American forests and Indonesian islands, had higher rates of "speciation" -- the formation of new and distinct species -- over the last 25 million years.For example, speciation rates for birds in hotspots of the Indo-Malay region were, on average, 36% higher than that region's non-hotspot areas. Hotspots in the Neotropics had almost 28% greater bird speciation compared to non-hotspots."Species generation is faster in the tropics, but we can now see it is extra-quick in these hotspots of biodiversity," said study lead author Dr Javier Igea, also from Cambridge's Department of Plant Sciences."More rainfall and hotter temperatures bolster the ecosystems of tropical hotspots, producing more plants, more animals that feed on those plants, and so on," he said."The greater available energy and range of habitats within these hotspots supported the acceleration of species diversification."The tropical hotspot of Madagascar, for example, holds 12 species of true lemur that diversified in the last ten million years. All of the 17 species of earthworm mice endemic to the Philippines were generated in the last six million years.The famously diverse finches Darwin found in the Galapagos Islands, as featured in his revolutionary book However, when it came to the more temperate regions of the Nearctic (North America) and Palearctic (Eurasia and North Africa), the researchers discovered a different story.While the hotspots of these regions also had a wider range of resource and habitat than neighbouring areas, the data from the evolutionary -- or phylogenetic -- trees revealed that most of their animals "speciated" somewhere else."Biodiversity hotspots in temperate zones have been shaped mainly by migration that occurred during the last 25 million years," said Igea."We suspect that this influx of immigrant species resulted from climate fluctuations across millions of years, particularly cooling. Biodiversity hotspots may have acted as a refuge where more species could survive in harsh climatic conditions," he said.Igea points to species such as the Iberian lynx, now a native of the Mediterranean Basin hotspot, but found in central Europe during the Pleistocene -- prior to the last Ice Age.Or the yellow-billed magpie, which became isolated in California after becoming separated from its ancestral species -- most likely due to glaciations -- over three million years ago."We found that hotspots across the world all have a greater complexity of habitats and more environmental energy, but the processes that drive the biodiversity are very different for tropical and temperate zones," Igea said.For Tanentzap, the importance of species migration in temperate regions suggests that maintaining connectivity between hotspots should be a priority for future conservation efforts."Many of these hotspot regions have species found nowhere else on Earth, yet face devastating levels of habitat loss. Protecting these areas is vital to conserving the natural world's diversity," he said.
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Extinction
| 2,019 |
February 6, 2019
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https://www.sciencedaily.com/releases/2019/02/190206115559.htm
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Social behavior of western lowland gorillas
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A new study published in the journal
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According to the authors, this social behaviour may have played an important role in the evolutionary story of the species, easing the exchange of information and a better exploitation of trophic resources. However, this social dynamics may have worsened the impact of some infectious diseases in the population of gorillas, experts warn. In this context, epidemic Ebola virus outbreaks, which affected the primate population in Congo between 2002 and 2004, caused the disappearance of 95 % of this ape, causing this species to be in critical danger of extinction according to the Red List of threatened species by the International Union for the Conservation of Nature (IUCN).In the new study, carried out in the Ngaga Forest in the Republic of the Congo, counts on the participation of German Illera (Great Apes Conservation/Research Odzala-Lossi and SPAC gGmbH, Republic of the Congo), Giovanni Forcina, Rubén Bernardo-Madrid, Eloy Revilla and Carles Vilà (Doñana Biological Station EBD-CSIC) and other experts of the University of Rennes (France).The ecology and behaviour of the western lowland gorilla inside the equatorial forests was an enigma so far. Since the first scientific studies started, differences between the behaviour of these two African primates were known: the western lowland gorilla (Unlike the mountain gorilla, which has aggressive and infrequent interactions between families, the western lowland gorilla was known to have frequent and peaceful interaction between members of the families. However, due a low visibility inside the forests, western lowland gorillas that had been studied in bais, typical open clearings which are the meeting point for families of the species to feed from plants rich in mineral salts.As part of the study, the experts conducted a scientific monitoring over five years to three families of the western lowland gorilla in the same heart of the Congo forest. According to the conclusions, interaction between individuals from different families is common and peaceful so the individuals eat and play together with no signs of aggression.Regarding methodology, experts profiled an image of the social structure and parentage relations of more than 120 gorillas through the genetic analysis of faeces samples taken over four months -in families and single individuals- in the Ngaga forest.Data show families have a dynamic social structure in which individuals conduct frequent changes among family groups. Young individuals are usually outside the family and enter temporarily other family groups in which they have no close relatives. This social behaviour could be linked to the lack of infanticide records in this species, experts note.This new study shows the image of a modular society featured by the existence of strong ties which do not avoid the transfer of individuals between different families and a high degree of tolerance between their members. The results of this study show the importance of complementing in situ monitoring studies with non-invasive genetic analysis to find the structure and social dynamics in animal species which are hard to have access to. At the same time, conclusions highlight the importance of social behaviour in disease transmission and the development of effective conservation strategies in the long run.
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Extinction
| 2,019 |
February 6, 2019
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https://www.sciencedaily.com/releases/2019/02/190206101123.htm
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'Twilight Zone' could help preserve shallow water reefs
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Corals lurking in deeper, darker waters could one day help to replenish shallow water reefs under threat from ocean warming and bleaching events, according to researchers.
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The University of Queensland and the ARC Centre of Excellence for Coral Reef Studies examined corals from the ocean's 'twilight zone' at depths below 30 metres.Dr Gal Eyal, the Marie Sk?odowska-Curie fellow at UQ's Marine Palaeoecology Lab, said the mesophotic zone is deeper than recreational SCUBA diving limitations."Corals in this zone are often overlooked or ignored but occupy at least 50 per cent of unique coral habitats," Dr Eyal said."Light is limited when descending to these depths, so it's a major factor in the livelihood of the ecosystems there."We showed that strictly mesophotic coral can grow much faster when it is transplanted to a shallow reef light environment."In deeper waters the corals experience light limitations, so they allocate their energy accordingly."Dr Eyal said the improved performance of the corals collected from 40 to 50m depth and placed in shallow water conditions was promising, but more research was needed to better understand the physiological processes controlling the phenomena."This study shows that while there are restrictions in nature currently preventing the persistence of these corals in shallow reefs, the potential is there.""The 'twilight-zone' needs to be considered an important zone of coral reefs, instead of the marginal environment it is often viewed as today."Dr Eyal said the deep could reveal many more secrets that could help researchers understand coral reefs."Coral reefs are diminishing worldwide due to global warming, so we strongly advocate for the protection and conservation of these deeper and unique environments in order to secure a future for coral reefs."
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Extinction
| 2,019 |
February 6, 2019
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https://www.sciencedaily.com/releases/2019/02/190206091348.htm
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Tree loss from bark-beetle infestation impacts elk habitat
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Although elk typically adapt to forest disturbances such as forest fires and logging, a new
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Avoidance of beetle-killed forest by elk during the summer has led to a decline in preferred habitat for elk that will be of importance to many wildlife and land managers responsible for managing elk populations in areas impacted by the bark-beetle epidemic."Although it is common following forest disturbances for elk to seek out and capitalize on the resulting increases in highly palatable and nutritious forage, during the summer months, elk in our study area fairly consistently avoided beetle-kill. This result is somewhat counter to how we typically think elk respond to forest disturbances," said lead author Bryan G. Lamont, of the University of Wyoming. "It appears there are some subtle, but real differences between disturbances such as forest fires and the bark-beetle epidemic."Lamont noted that for elk in the study, the increases in the number of downed trees and loss of canopy cover seemed to outweigh the meager increases in understory in bark-beetle affected areas. "Ultimately this means that if elk are avoiding beetle-kill areas, this translates to much less forest habitat that elk typically would utilize during the summer," he said.
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Extinction
| 2,019 |
February 1, 2019
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https://www.sciencedaily.com/releases/2019/02/190201130603.htm
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Palm oil not the only driver of forest loss in Indonesia
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Large-scale agriculture, primarily for growing oil palms, remains a major cause of deforestation in Indonesia, but its impact has diminished proportionately in recent years as other natural and human causes emerge, a new Duke University study finds.
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"In the late 2000s, large-scale plantations were responsible for more than half of Indonesia's loss of primary natural forests," said Kemen G. Austin, a 2018 doctoral graduate of Duke's Nicholas School of the Environment, who led the study. "This trend peaked from 2008 to 2010, when an average of 600,000 hectares of forest was lost annually -- 57 percent of it driven by the expansion of these massive farms.""From 2014 to 2016, an average of more than 800,000 hectares of primary forest was lost annually, but large-scale plantations accounted for only 25 percent of it," Austin said. "So although the overall rate of deforestation grew, other causes were responsible for most of it."The conversion of forests to grasslands rose sharply in 2015 and 2016 when El Niño caused severe drought and higher-than-normal fire activity on many of the nation's islands, she noted.Small-scale farming, which has largely been overshadowed by plantation-scale agriculture as a driver of deforestation, was also found to play a bigger role, accounting for about one-quarter of all forest loss. This suggests the importance of designing forest management interventions that take the values and requirements of small-holder farmers into account too, said Austin, who is now a senior policy analyst at RTI International.Mining and logging roads were also found to be important drivers of deforestation at different times during the study, particularly on the local level."The takeaway message for policymakers and conservationists is that the causes of forest loss in Indonesia are much more varied than we previously thought. They change from place to place and over time," Austin said. "Even though oil palm is the first thing that pops into most people's head when they think about deforestation in Indonesia, it's not the only cause, and we need to adjust our policies and practices to account for that."Austin and her colleagues published their peer-reviewed findings Feb. 1 in Their study is the first to document the changing causes of deforestation occurring in Indonesia at the national scale and at the local level on each of the country's major developed islands. Some global studies previously have included nationwide data from Indonesia, Austin noted, but not at such a fine scale."Using 15 years of high-spatial-resolution Google Earth imagery and newly available global datasets on forest loss let us zero in on the causes of deforestation at each location and see how they vary from place to place and over time," Austin said. "For instance, logging is still driving deforestation on the island of Papua, but on Sumatra and Kalimantan, it's the oil palm industry and El Niño-driven fires that are the primary drivers."Indonesia has experienced one of the highest rates of primary natural forest loss in the tropics in recent years. The loss of these forests -- which absorb and store vast amounts of climate-warming carbon dioxide, provide habitat for thousands of species, and help control erosion and flooding -- has become a cause of global environmental concern.The declining role of large-scale agriculture in causing forest loss of late may stem from the success of conservation policies the Indonesian government has put into place since 2011 and by voluntary commitments to sustainability by corporations that own or manage oil palm or timber plantations, Austin said. It could also be driven by economic factors, such as falling commodity prices or increased international competition.
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Extinction
| 2,019 |
January 31, 2019
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https://www.sciencedaily.com/releases/2019/01/190131162517.htm
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Climate change could make corals go it alone
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Climate change is bad news for coral reefs around the world, with high ocean temperatures causing widespread bleaching events that weaken and kill corals. However, new research from The University of Texas at Austin has found that corals with a solitary streak -- preferring to live alone instead of in reef communities -- could fare better than their group-dwelling relatives.
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The findings, which could potentially give clues about where modern reef conservation efforts should be focused, are based on a survey of coral species that survived during a period of warming in Earth's past that resembles the climate change of today. And while the research suggests that corals may cope better with climate change than expected, the isolated lifestyles of the survivors could mean that the coral ecosystems of the future could be bleak."Although corals themselves might survive, if they're not building reefs, that's going to cause other problems within the ecosystem," said Anna Weiss, a Ph.D. candidate at the UT Jackson School of Geosciences who led the research. "Reefs support really big, diverse communities."The environment isn't the only thing facing a bleak future. The coral species with the best odds of survival are drab in comparison to colorful reef corals.The research was published in the journal The study examined coral species that lived about 56 million years ago during the transition of the late Paleocene to the Early Eocene, a time interval that lasted about 200,000 years and that included spikes in temperature and atmospheric carbon dioxide. The spikes created global temperatures that are about 14 degrees Fahrenheit (8 degrees Celsius) warmer than they are today and made oceans more acidic. The researchers tracked coral over this period for insight about how coral living today might respond to contemporary climate change.They carried out the work using an international fossil database. The database includes information about when hundreds of coral species lived and their physical traits such as how a species ate, the type of environment where it lived, how it reproduced and whether it was able to form colonies. The research revealed that at the global level, solitary coral species increased in diversity during the warm period. They also found that certain traits that probably helped corals cope with the effects of climate change were associated with coral survival.One of the traits is catching food independently rather than getting nutrients from heat-sensitive algae that live in certain coral tissues but leave, causing coral bleaching, when the water gets too warm. Another trait is preferring to live on stony seafloor bottoms where the water is cooler rather than on carbonate rock in warmer and shallower areas. Researchers said that understanding which traits are connected to coral survival in the past could be a useful lens for predicting how corals today might respond to ongoing warming and could help focus conservation efforts."Conservationists want to know what traits might help different species survive global change. If we can find patterns to survival, we may be able to help our reefs do better today and in the coming years," said Martindale.Carl Simpson, a paleobiologist and assistant professor at the University of Colorado Boulder who was not involved with the research, said it was interesting to see how different coral traits were linked to different survival outcomes."It can be a little bit of a subtle thing, because you would think that they're all susceptible to environmental change and warming and acidification," he said. "But it turns out that there's enough variety in the way that they live that they actually respond differently."Finding out the corals on the global level were able to adapt to climate change in the past suggests that they may be able to do it again in the future. However, Weiss notes that perspective is a "best-case scenario." Warming during the Paleocene happened over thousands of years, whereas the rate of warming today is occurring over decades to centuries. It's unknown whether corals will be able to cope with the rapid pace of change that is happening in the present. Weiss said that more research that explores how specific communities of corals -- rather than corals as a whole -- responded to warming in the past could help improve scientists' understanding of how corals in different environments around the world might respond to climate change today.The research was supported by the Jackson School of Geosciences.
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Extinction
| 2,019 |
January 31, 2019
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https://www.sciencedaily.com/releases/2019/01/190131104951.htm
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Citizen scientists discover pinhead-sized beetle in Borneo
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How many citizen scientists does it take to discover a new species? A recent expedition to the Ulu Temburong forest in Borneo proved that you only need 10 enthusiasts with no professional training, yet fueled with curiosity and passion for the outdoors, to find a new beetle the size of a pinhead in leaf litter.
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The species, named Unlike other science/adventure trips, Taxon Expeditions gives a unique opportunity for laypeople, or citizen scientists, to describe and publish new species of animals and focus on the thousands of 'little things that run the world'. Thanks to the initiative, they learn about tropical biology techniques while participating in the process of taxonomy and the study of hidden biodiversity.The new beetle, for example, is one of hundreds of thousands of tiny beetle species that inhabit the leaf litter of tropical forests and have remained unknown and scientifically unnamed up to our days.In a Entomologist and founder of Taxon Expeditions, Dr. Iva Njunjic explains: 'We introduce the general public to all these tiny, beautiful, and completely unknown animals, and show them that there is a whole world still to be discovered.'Last year, another survey in Borneo organised by Taxon Expeditions ended up with the description of a new water beetle species (
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Extinction
| 2,019 |
January 19, 2021
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https://www.sciencedaily.com/releases/2021/01/210119102859.htm
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50 million-year-old fossil assassin bug has unusually well-preserved genitalia
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The fossilized insect is tiny and its genital capsule, called a pygophore, is roughly the length of a grain of rice. It is remarkable, scientists say, because the bug's physical characteristics -- from the bold banding pattern on its legs to the internal features of its genitalia -- are clearly visible and well-preserved. Recovered from the Green River Formation in present-day Colorado, the fossil represents a new genus and species of predatory insects known as assassin bugs.
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The find is reported in the journal Discovered in 2006 by breaking open a slab of rock, the fossilized bug split almost perfectly from head to abdomen. The fracture also cracked the pygophore in two. A fossil dealer later sold each half to a different collector, and the researchers tracked them down and reunited them for this study.Being able to see a bug's genitalia is very helpful when trying to determine a fossil insect's place in its family tree, said Sam Heads , a paleontologist at the Illinois Natural History Survey and self-described fossil insect-genitalia expert who led the research with Daniel Swanson, a graduate student in entomology at the University of Illinois Urbana-Champaign.Species are often defined by their ability to successfully mate with one another, and small differences in genitalia can lead to sexual incompatibilities that, over time, may result in the rise of new species, Swanson said. This makes the genitalia a good place to focus to determine an insect species.But such structures are often obscured in compression fossils like those from the Green River Formation."To see these fine structures in the internal genitalia is a rare treat," Swanson said. "Normally, we only get this level of detail in species that are living today."The structures visible within the pygophore include the basal plate, a hardened, stirrup-shaped structure that supports the phallus, he said. The fossil also preserved the contours of the phallotheca, a pouch into which the phallus can be withdrawn.The find suggests that the banded assassin bugs, a group to which the new specimen is thought to belong, are about 25 million years older than previously thought, Swanson said."There are about 7,000 species of assassin bug described, but only about 50 fossils of these bugs are known," he said. "This just speaks to the improbability of even having a fossil, let alone one of this age, that offers this much information."This is not the oldest fossil bug genitalia ever discovered, however."The oldest known arthropod genitalia are from a type of bug known as a harvestman that is 400-412 million years old, from the Rhynie Chert of Scotland," Heads said. "And there are also numerous fossil insects in amber as old as the Cretaceous Period with genitalia preserved."However, it is almost unheard of for internal male genitalia to be preserved in carbonaceous compressions like ours," he said.The researchers named the new assassin bug Aphelicophontes danjuddi. The species name comes from one of the fossil collectors, Dan Judd, who donated his half of the specimen to the INHS for study.
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New Species
| 2,021 |
December 4, 2020
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https://www.sciencedaily.com/releases/2020/12/201204110246.htm
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Biological diversity evokes happiness
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Under the current pandemic conditions, activities out in nature are a popular pastime. The beneficial effects of a diverse nature on people's mental health have already been documented by studies on a smaller scale. Scientists of the Senckenberg Gesellschaft für Naturforschung, the iDiv, and the University of Kiel now examined for the first time whether a diverse nature also increases human well-being on a Europe- wide scale.
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To this end, the researchers used the data from the "2012 European quality of Life Survey" to study the connection between the species diversity in their surroundings and the life satisfaction in more than 26,000 adults from 26 European countries. Species diversity was measured based on the diversity of avian species, as documented in the European breeding bird atlas."Europeans are particularly satisfied with their lives if their immediate surroundings host a high species diversity," explains the study's lead author, Joel Methorst, a doctoral researcher at the Senckenberg Biodiversity and Climate Research Centre, the iDiv, and the Goethe University in Frankfurt. "According to our findings, the happiest Europeans are those who can experience numerous different bird species in their daily life, or who live in near-natural surroundings that are home to many species."Birds are well-suited as indicators of biological diversity, since they are among the most visible elements of the animate nature -- particularly in urban areas. Moreover, their song can often be heard even if the bird itself is not visible, and most birds are popular and people like to watch them. But there is also a second aspect that affects life satisfaction: the surroundings. A particularly high number of bird species can be found in areas with a high proportion of near-natural and diverse landscapes that hold numerous greenspaces and bodies of water."We also examined the socio-economic data of the people that were surveyed, and, much to our surprise, we found that avian diversity is as important for their life satisfaction as is their income," explains Prof. Dr. Katrin Böhning-Gaese, director of the Senckenberg Biodiversity and Climate Research Centre, professor at the Goethe University in Frankfurt am Main, and member of the iDiv. This result becomes particularly obvious when both values increase by ten percent. Fourteen additional bird species in the vicinity raise the level of life satisfaction at least as much as an extra 124 Euros per month in the household account, based on an average income of 1,237 Euro per month in Europe.According to the study, a diverse nature therefore plays an important role for human well-being across Europe -- even beyond its material services. At the same time, the researchers draw attention to impending health-related problems. "The Global Assessment 2019 by the World Biodiversity Council IPBES and studies of avian species in agricultural landscapes in Europe clearly show that the biological diversity is currently undergoing a dramatic decline. This poses the risk that human well-being will also suffer from an impoverished nature. Nature conservation therefore not only ensures our material basis of life, but it also constitutes an investment in the well-being of us all," adds Methorst in conclusion.
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New Species
| 2,020 |
November 30, 2020
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https://www.sciencedaily.com/releases/2020/11/201130113540.htm
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Warbler coloration shaped by evolution via distinct paths
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Two genes that are important for the diverse colors and patterns of warbler plumage have evolved through two very different processes, according to a new study led by Penn State researchers. These evolutionary processes could help explain the rapid evolution of these songbirds into so many unique species.
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"Wood warblers are an incredibly colorful and diverse group of birds, with more than a hundred species in total," said Marcella Baiz, postdoctoral researcher at Penn State and first author of the paper. "These species arose very quickly in evolutionary time in what biologists call a species radiation. To better understand this radiation, we studied genetic regions related to plumage coloration within a particularly colorful subset of warblers."The research team sequenced the genomes of all 34 species within the Setophaga genus of wood warblers and created a phylogenetic tree that clarifies how each species is related to one another. Then, they focused on nine closely related pairs of "sister species." Each pair is the result of one species diverging into two. Seeing if similar evolutionary processes are at play in each of the pairs allowed the researchers to gain a better understanding of the overall radiation.A paper describing their results appears today (Nov 30.) in the journal "In most cases it is difficult to get at the genes underlying the diversification process because it can be hard to link specific genes to specific traits, like colors," said David Toews, assistant professor of biology at Penn State and leader of the research team. "But many species of warblers readily interbreed, producing hybrid offspring with a mix of the parent species' traits, so we were previously able to link certain color patterns with their underlying genetic regions. In this study, we focused on two coloration genes, but were able to study them across all the species in this large genus, to give us a window into the rest of the radiation."The first gene, the Agouti-signaling protein (ASIP), is involved in producing the pigment melanin, which underlies brown and black plumage in these warblers. Within each pair of sister species where there were differences in the amount or location of the black or brown in their plumage, the team predictably found genetic differences near ASIP."We created an evolutionary tree based solely on the ASIP gene region, which more clearly shows how the gene has changed across the genus," said Baiz. "The patterns in this gene tree mirror patterns in the phylogenetic tree based on what we see across the whole genome. This implies that the differences we see in ASIP resulted from mutations that arose independently in different species. However, the gene tree from the second gene, BCO2, showed a very different pattern that did not match up with the whole genome tree, which suggests different processes are at play."The second gene, beta-carotene oxygenate 2 (BCO2), is involved in producing carotenoid pigments, which result in bright yellow, red, and orange plumage. The researchers suggest that a process called introgression -- the exchange of genes between species that have evolved separately -- may explain why the pattern of genetic changes in BCO2 didn't align with the overall radiation of the group."Introgression can occur when two separate species hybridize, and the hybrid offspring go on to mate with one of the original species," said Baiz. "After several generations, genetic material from one species can be incorporated into the other. The signal of this kind of ancient introgression can be maintained in the genomes of living individuals -- like how ancestry tests can reveal how many Neanderthal genes you have. In this instance, we unexpectedly found evidence for ancient introgression at BCO2 in two otherwise distantly related warblers in this genus."The researchers found evidence of introgression involving the yellow warbler and magnolia warbler and involving the prairie warbler and vitelline warbler, all species with colorful carotenoid coloration in their feathers. However, they note that with the current data it is difficult to tell the directionality of the gene transfer."One possibility is that the magnolia warbler version of BCO2 introgressed into the yellow warbler, and this 'new to them' version produced a broader deposition of carotenoids in the feathers of the yellow warbler," said Toews. "It is fun to think that ancient introgression is what made the yellow warbler so yellow!"This is one of the first examples of carotenoid gene transfer among vertebrates. Collectively, the results of this study suggest that both introgression and a more standard mode of evolution, where mutations occur and are passed from parent to offspring, have played a role in generating the diversity of colors in this genus and could have helped enable the extreme diversification of warblers.In the future, the researchers hope to link specific mutations in these genes to changes in plumage coloration and to map out the molecular pathways involved in pigment production. They would also like to expand their study to all 110 species of warblers."There's a possibility that there may be introgression from another genus entirely," said Toews. "Expanding to other warblers would allow us to explore this possibility, and to more broadly understand the radiation of these fascinating birds."
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New Species
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November 16, 2020
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https://www.sciencedaily.com/releases/2020/11/201116125619.htm
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Paleontologists uncover three new species of extinct walruses in Orange County, California
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Millions of years ago, in the warm Pacific Ocean off the coast of Southern California, walrus species without tusks lived abundantly.
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But in a new study, Cal State Fullerton paleontologists have identified three new walrus species discovered in Orange County and one of the new species has "semi-tusks" -- or longer teeth.The other two new species don't have tusks and all predate the evolution of the long iconic ivory tusks of the modern-day walrus, which lives in the frigid Arctic.The researchers describe a total of 12 specimens of fossil walruses from Orange, Los Angeles and Santa Cruz counties, all estimated to be 5 to 10 million years old. The fossils represent five species, with two of the three new species represented by specimens of males, females and juveniles.Their research, which gives insights on the dental and tusk evolution of the marine mammal, was published today in the Geology graduate Jacob Biewer, and his research adviser James F. Parham, associate professor of geological sciences, are authors of the study, based on fossil skull specimens.Parham and Biewer worked with Jorge Velez-Juarbe, an expert in marine mammals at the Natural History Museum of Los Angeles County, who is a co-author of the paper. Velez-Juarbe is a former postdoctoral scholar in Parham's lab and has collaborated on other CSUF fossil research projects. Parham is a research associate at the museum, which provides research opportunities for him and his students.The researchers teamed to study and describe the anatomy of the specimens, most of which are part of the museum's collection."Orange County is the most important area for fossil walruses in the world," said Biewer, first author of the paper who conducted the research for his master's thesis. "This research shows how the walruses evolved with tusks."Today, there is only one walrus species and its scientific name is Odobenus.For the new species found in Orange County, the researchers named the semi-tusked walrus, Osodobenus eodon, by combining the words Oso and Odobenus. Another is named Pontolis kohnoi in honor of Naoki Kohno, a fossil walrus researcher from Japan. Both of these fossils were discovered in the Irvine, Lake Forest and Mission Viejo areas.Osodobenus eodon and Pontolis kohnoi are both from the same geological rock layer as the 2018 study by Parham and his students of another new genus and species of a tuskless walrus, Titanotaria orangensis, named after CSUF Titans. These fossils were found in the Oso Member of the Capistrano Formation, a geological formation near Lake Forest and Mission Viejo.The third new walrus species, Pontolis barroni, was found in Aliso Viejo, near the 73 Toll Road. It is named after John Barron, a retired researcher from the U.S.Geological Survey and world expert on the rock layer where the specimens were found, Parham said.Analysis of these specimens show that fossil walrus teeth are more variable and complex than previously considered. Most of the new specimens predate the evolution of tusks, Parham said."Osodobenus eodon is the most primitive walrus with tusk-like teeth," Parham said. "This new species demonstrates the important role of feeding ecology on the origin and early evolution of tusks."Biewer explained that his work focused on getting a better understanding of the evolutionary history of the walrus in regards to its teeth."The importance of dental evolution is that it shows the variability within and across walrus species. Scientists assumed you could identify certain species just based on the teeth, but we show how even individuals of the same species could have variability in their dental setup," said Biewer, who earned a master's degree in geology in 2019."Additionally, everyone assumes that the tusks are the most important teeth in a walrus, but this research further emphasizes how tusks were a later addition to the history of walruses. The majority of walrus species were fish eaters and adapted to catching fish, rather than using suction feeding on mollusks like modern walruses."Biewer, now a paleontologist in the Modesto area, also examined whether climate changes in the Pacific Ocean had an impact on ancient walruses. His work suggests that a rise in water temperature helped to boost nutrients and planktonic life, and played a role in the proliferation of walruses about 10 million years ago, which may have contributed to their diversity.For the fossil walrus research project, geology graduate Jacob Biewer spent hours in the lab measuring and describing the walrus bones."I sat many hours with a handy caliper taking notes on the lengths of teeth and width of skulls, among many other measurements," he said. "Describing bones is much more in depth and meticulous than it sounds. There are traits that the bones of each walrus species have -- the size, shape and number of teeth. I recorded how the bones are different from, or similar to, other extinct walrus species."Biewer, a paleontologist who lives in Modesto, noted that despite the pandemic, he and Parham worked on the scientific paper with 300 miles of social distancing.Completing his first journal publication, based on his master's work, and conducting the research project helped him to understand scientific methods and techniques that he now uses in his career, where he monitors construction sites for paleontological resources. He also teaches undergraduate geology courses at Cal State Stanislaus, where he earned a bachelor's degree in geology, and is considering pursuing a doctorate."The experiences I had in conducting this research, especially the presentations at national paleontological conferences, led to a big increase in my confidence in my scientific abilities," Biewer said. "I credit my time working with Dr. Parham directly to the achievements in my current employment -- from the skills he imparted to the doors he helped open."
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New Species
| 2,020 |
November 16, 2020
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https://www.sciencedaily.com/releases/2020/11/201116112922.htm
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Tiny cave snail with muffin-top waistline rolls out of the dark in Laos
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A new species of tiny cave snail that glistens in the light and has a muffin-top-like bulge, was discovered by Marina Ferrand of the French Club Etude et Exploration des Gouffres et Carrie?res (EEGC), during the Phouhin Namno caving expedition in Tham Houey Yè cave in Laos in March 2019. The new species, Laoennea renouardi, is 1.80 mm tall and is named after the French caver, Louis Renouard, who explored and mapped the only two caves in Laos known to harbor this group of tiny snails. Only two species of Laoennea snail are known so far, L. carychioides and now, L. renouardi.
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Caver and scientist, Dr. Adrienne Jochum, affiliated with the Natural History Museum BernUniversity of Bern (Switzerland), as well as the Senckenberg Research Institute and Natural History Museum (Frankfurt, Germany) described the new species and its cave habitat together with co-authors: Estée Bochud, Natural History Museum Bern; Quentin Wackenheim, Laboratoire de Géographie Physique (Meudon, France) and Laboratoire Trajectoires (Nanterre, France); Marina Ferrand, EEGC; and Dr. Adrien Favre, Senckenberg Research Institute and Natural History Museum, in the open-access, peer-reviewed journal "The discovery and description of biodiversity before it disappears is a major priority for biologists worldwide. The caves in Laos are still largely underexplored and the snails known from them remain few in number," points out Dr. Jochum.The fact that two species of tiny cave snails of the same group were found in two caves located in two independent karstic networks 3.4 km apart, caused the authors to question evolutionary processes in these underground hotspots of biodiversity. The authors hypothesise that the two caves might have been connected during the Quaternary, around 100-200 thousand years ago. In time, the river Yè might have formed a barrier, thus disconnecting the cave systems and separating the populations. As a result, the snails evolved into two different species.
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New Species
| 2,020 |
November 16, 2020
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https://www.sciencedaily.com/releases/2020/11/201116075719.htm
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Genetic code evolution and Darwin's evolution theory should consider DNA an 'energy code'
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Darwin's theory of evolution should be expanded to include consideration of a DNA stability "energy code" -- so-called "molecular Darwinism" -- to further account for the long-term survival of species' characteristics on Earth, according to Rutgers scientists.
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The iconic genetic code can be viewed as an "energy code" that evolved by following the laws of thermodynamics (flow of energy), causing its evolution to culminate in a nearly singular code for all living species, according to the Rutgers co-authored study in the journal "These revelations matter because they provide entirely new ways of analyzing the human genome and the genome of any living species, the blueprints of life," said senior author Kenneth J. Breslauer, Linus C. Pauling Distinguished University Professor in the Department of Chemistry and Chemical Biology in the School of Arts and Sciences at Rutgers University-New Brunswick. He is also affiliated with the Rutgers Cancer Institute of New Jersey. "The origins of the evolution of the DNA genetic code and the evolution of all living species are embedded in the different energy profiles of their molecular DNA blueprints. Under the influence of the laws of thermodynamics, this energy code evolved, out of an astronomical number of alternative possibilities, into a nearly singular code across all living species."Scientists investigated this so-called "universal enigma," probing the origins of the astounding observation that the genetic code evolved into a nearly uniform blueprint that arose from trillions of possibilities.The scientists expanded the underpinnings of the landmark "survival of the fittest" Darwinian evolutionary theory to include "molecular Darwinism." Darwin's revolutionary theory is based on the generational persistence of a species' physical features that allow it to survive in a given environment through "natural selection." Molecular Darwinism refers to physical characteristics that persist through generations because the regions of the molecular DNA that code for those traits are unusually stable.Different DNA regions can exhibit differential energy signatures that may favor physical structures in organisms that enable specific biological functions, Breslauer said.Next steps include recasting and mapping the human genome chemical sequence into an "energy genome," so DNA regions with different energy stabilities can be correlated with physical structures and biological functions. That would enable better selection of DNA targets for molecular-based therapeutics.Jens Völker, an associate research professor in Rutgers-New Brunswick's Department of Chemistry and Chemical Biology, co-authored the study, along with first author Horst H. Klump at the University of Cape Town.
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New Species
| 2,020 |
November 13, 2020
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https://www.sciencedaily.com/releases/2020/11/201113141832.htm
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The Popovich of floral nectar spurs
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When it came to naming a gene that could lead to new insights on a crucial feature of evolution, the Harvard Organismic and Evolutionary Biology alumna leading the project aimed for something rather tongue in cheek. She called it POPOVICH, after San Antonio Spurs coach and president Gregg Popovich.
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Evangeline Ballerini, Ph.D. '10, an assistant professor of biological sciences at California State University, Sacramento, said she and her collaborators -- including Harvard's Elena Kramer -- settled on the name because the newly discovered gene calls the shots for floral nectar spurs the way Popovich does for his NBA team."I ended up choosing to name it after Gregg Popovich, in part, because the gene plays a regulatory role in spur development, kind of like a coach controls the development of their team," said Ballerini, who is a long-time Golden State Warriors fan and a part-time Celtics fan because of her time in the Boston area, but respects the Spurs and admires Popovich's leadership.The work is described in a recently published study in Nectar spurs are the hollow tubes that bulge out from a number of flowers and are crucial to increasing biodiversity among flowering plants that have them. In many cases, species with nectar spurs are much more diverse than their close relative without this novel trait.In the paper, the scientists identify the gene critical to controlling the development of these spurs in the common columbine, or Aquilegia. They found it acts as a master regulator that appears to control the creation of the spurs by regulating the activity of other genes, the way a coach decides who plays and when.Aside from the quirky NBA reference, what really has evolutionary biologists excited about the discovery is that the findings have the potential to help them understand how organisms get their vast array of shapes and traits, and then how those traits evolve.Nectar spurs are considered a key innovation in flowers, meaning they are considered a novel feature -- one that helps organisms make the greatest use of their environment and leads to a diversity boom. Animals that evolved to have wings, for instance, have spun off into number of different species over millions of years. Other key innovations are eyes or the backbone in mammals.Most key innovations happened deep in the past, making identifying their origin increasingly difficult. In the group of plants the researchers studied, however, floral nectar spurs have only been around for about 5 to 7 million years."Given that the Aquilegia nectar spur evolved relatively recently and is formed by modifications to a single floral organ, it provides a unique opportunity to begin to dissect the developmental and genetic basis of a key innovation, which, in turn, will provide insight into its origin," the researchers wrote.The researchers believe the gene is among the first key innovations for which scientists have identified the critical gene, opening the door to a number of areas in understanding how form and morphology are achieved in flowers and other living things."We're particularly interested in novel features that seem to be very important for promoting speciation events," said Kramer, Bussey Professor of Organismic and Evolutionary Biology and chair of the Department of Organismic and Evolutionary Biology. "In terms of a morphological trait, like the nectar spur, we're asking: How did development [of the species] change? ... It gives us, essentially, a handle, a starting place to try to start understanding this genetic network."Researchers made the discovery using a combination of techniques that included genetic sequencing and crossing species, and gene expression analyses. One of the keys was using a species of the Aquilegia native to China and known to be the only member of that genus, out of 60 to 70 species, to lack nectar spurs.The team started by repeating a 1960 study by the Russian geneticist W. Pra?mo that crossed the spurless flower with a spurred species and suggested that a single, recessive gene was responsible for spur loss. Unlike Pra?mo, they had the genetic tools to finish the job, and sequenced the genome of about 300 offspring. That narrowed the search to just over 1,000 genes. Further genetic sleuthing led them to POPOVICH, which they call POP for short, and confirmed it using a genetically modified virus that knocks down, or suppresses, targeted genes."We took a species that has spurs and normally has POP expression, and we downregulated the expression of POP," Kramer said. "We showed that it lost its spurs, and that result was the thing that ties it all together. Not only is this a gene that's specifically expressed in spurs, but when you knock it down, it loses its spurs."While this is all strong evidence, more work is needed to confirm their findings."There are several directions that we'd like to go in, including trying to figure out how POP expression is controlled, which genes POP regulates the expression of, and what the POP gene is doing in the spurless relatives of Aquilegia," Ballerini said.
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New Species
| 2,020 |
November 10, 2020
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https://www.sciencedaily.com/releases/2020/11/201110133154.htm
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Fossil shark turns into mystery pterosaur
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Palaeontologists have made a surprising discovery while searching through 100-year-old fossil collections from the UK -- a new mystery species of pterosaur, unlike anything seen before.
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Lead author of the project, University of Portsmouth PhD student Roy Smith, discovered the mystery creature amongst fossil collections housed in the Sedgwick Museum of Cambridge and the Booth Museum at Brighton that were assembled when phosphate mining was at its peak in the English Fens between 1851 and 1900. These fossils found while workmen were digging phosphate nodules were frequently sold to earn a little bit of extra money.It was while Smith was examining the fossils of shark spines that he made the amazing discovery. The fossils were actually fragments of jaws of toothless pterosaurs, which do indeed resemble shark fin spines, but there are many subtle differences that allow them to be distinguished.Smith says: "One such feature are tiny little holes where nerves come to the surface and are used for sensitive feeding by the pterosaurs. Shark fin spines do not have these, but the early palaeontologists clearly missed these features. Two of the specimens discovered can be identified as a pterosaur called Ornithostoma, but one additional specimen is clearly distinct and represents a new species. It is a palaeontological mystery."Unfortunately, this specimen is too fragmentary to be the basis for naming the new species. Sadly, it is doubtful if any more remains of this pterosaur will be discovered, as there are no longer any exposures of the rock from which the fossils came. But I'm hopeful that other museum collections may contain more examples, and as soon as the Covid restrictions are lifted I will continue my search."Smith's supervisor, Professor Dave Martill, University of Portsmouth, says: "The little bit of beak is tantalising in that it is small, and simply differs from Ornithostoma in subtle ways, perhaps in the way that a great white egret might differ from a heron. Likely the differences in life would have been more to do with colour, call and behaviour than in the skeleton.""Pterosaurs with these types of beaks are better known at the time period from North Africa, so it would be reasonable to assume a likeness to the North African Alanqa (pictured below). This is extremely exciting to have discovered this mystery pterosaur right here in the UK."This find is significant because it adds to our knowledge of these ancient and fascinating flying prehistoric reptiles, but also demonstrates that such discoveries can be made, simply by re-examining material in old collections."
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New Species
| 2,020 |
October 6, 2020
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https://www.sciencedaily.com/releases/2020/10/201006114302.htm
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Evolution: Shifts in mating preference
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In their efforts to identify the genetic basis for differences in mate choice that keep two co-existing species of butterfly separate, evolutionary biologists at Ludwig-Maximlians-Universitaet (LMU) in Munich have identified five candidate genes that are associated with divergence in visual mating preferences.
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The evolution of a new species often involves a change in mating preference. This happens, for instance, when members of different populations of a given species cease to mate with each other because they no longer find potential partners sufficiently attractive. Two closely related species of tropical butterflies, Heliconius melpomene und Heliconius cydno, provide an interesting example of this phenomenon. The two species are often seen flying together, and crosses between them can result in fertile hybrid offspring. -- Nevertheless, individuals of the two species hardly ever mate with each other in the wild. How such behaviorally induced barriers to reproduction emerge is largely unknown. "When changes in behaviour are genetically hard-wired, as mate choice seems to be in our butterflies, they must involve alterations in sensation, that is, the stimuli they can detect, or changes in how these stimuli are processed," says LMU evolutionary biologist Dr. Richard Merrill. Together with members of his group, and collaborators at the Smithsonian Tropical Research Institute in Panama and at the University of Cambridge, he has now identified five genes that are linked to the different mating preferences of H. melpomene and H. cydno. As the authors report in the open access journal H. melpomene and H. cydno differ in the striking color patterns of their wings, which serve to warn off potential predators that they are distasteful. H. melpomene has black wings with red bars and thin yellow stripes, while H. cydno's wings feature white bars on a black background. Notably the males of each species show a marked attraction for females with the same 'color scheme' as themselves. In their quest for the genetic factors that underlie differences in these mating preferences, Merrill and his colleagues had previously identified three genomic regions which were associated with the different mating behaviors. One of these regions, on chromosome 18, had an especially strong effect on the degree of persistence with which the male pursues the female of his choice. Strikingly, a gene called optix, which controls the expression of the red bars on the wings of H. melpomene, lies within this same chromosomal segment. However, although this research revealed that one or more genes in this relatively short region of the chromosome must affect mate preference behaviors, the interval in question contains more than 200 genes.In the new study, Matteo Rossi, a PhD student working in Merrill's group, compared the sequences and activity of these genes in neural tissues -- including the central brain, optic structures and the 'ommatidia' (the retinal units that form the facets of the eye) -- of H. melpomene and H. cydno. They were able to identify five genes located within this interval that differed between the two species and were associated with their different visual preferences. Most importantly, three of these genes code for proteins that play key roles in neural signal transmission. "Overall, the nature of our candidate genes suggests that the different preferences for the wing coloration of potential partners are likely to be based on differences in the processing of the visual information. -- It seems that the two species do not differ with respect to what they see, but they react differently to the different color patterns," says Rossi. "In this way, over the course of evolution, mating preferences can change without affecting perceptions of other aspects of the environment."
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New Species
| 2,020 |
October 6, 2020
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https://www.sciencedaily.com/releases/2020/10/201006091244.htm
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Evolution in action: New Plant species in the Swiss Alps
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A new plant species named
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The emergence of a new species is generally thought to occur over long periods of time. But -- as the example of the plant "To characterize the responses to a fluctuating environment, the research team used high-throughput sequencing to analyze the time-course gene expression pattern of the three species in response to submergence. They found that the gene activity responsible for two parent traits were key for the survival of the new species in the novel habitat. First, Second, This work is mainly funded by the University Research Priority Program "Evolution in Action: From Genomes to Ecosystems," the Swiss National Science Foundation, Japan Science and Technology Agency, and the Human Frontier Science Program.
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New Species
| 2,020 |
October 2, 2020
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https://www.sciencedaily.com/releases/2020/10/201002091101.htm
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Cheating birds mimic host nestlings to deceive foster parents
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The common cuckoo is known for its deceitful nesting behaviour -- by laying eggs in the nests of other bird species, it fools host parents into rearing cuckoo chicks alongside their own. While common cuckoos mimic their host's eggs, new research has revealed that a group of parasitic finch species in Africa have evolved to mimic their host's chicks -- and with astonishing accuracy. The study is published in the journal
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Working in the savannahs of Zambia, a team of international researchers collected images, sounds and videos over four years to reveal a striking and highly specialised form of mimicry. They focused on a group of finches occurring across much of Africa called the indigobirds and whydahs, of the genus Vidua.Like cuckoos, the 19 different species within this group of finches forego their parental duties and instead lay their eggs in the nests of other birds. Each species of indigobird and whydah chooses to lay its eggs in the nests of a particular species of grassfinch. Their hosts then incubate the foreign eggs, and feed the young alongside their own when they hatch.Grassfinches are unusual in having brightly coloured and distinctively patterned nestlings, and nestlings of different grassfinch species have their own unique appearance, begging calls and begging movements. Vidua finches are extremely specialised parasites, with each species mostly exploiting a single host species.Nestlings of these 'brood-parasitic' Vidua finches were found to mimic the appearance, sounds and movements of their grassfinch host's chicks, right down to the same elaborately colourful patterns on the inside of their mouths."The mimicry is astounding in its intricacy and is highly species-specific," said Dr Gabriel Jamie, lead author on the paper and a research scientist in the University of Cambridge's Department of Zoology, and at the FitzPatrick Institute of African Ornithology, University of Cape Town.He added: "We were able to test for mimicry using statistical models that approximate the vision of birds. Birds process colour and pattern differently to humans so it is important to analyse the mimicry from their perspective rather than just relying on human assessments."While the mimicry is very precise, the researchers did find some minor imperfections. These may exist due to insufficient time for more precise mimicry to evolve, or because current levels of mimicry are already good enough to fool the host parents. The researchers think that some imperfections might actually be enhanced versions of the hosts' signal, forcing it to feed the parasite chick even more than it would its own.The mimetic adaptations to different hosts identified in the study may also be critical in the formation of new species, and in preventing species collapse through hybridisation."The mimicry is not only amazing in its own right but may also have important implications for how new species of parasitic finches evolve," added Professor Claire Spottiswoode, an author of the paper and a research scientist at both the University of Cambridge and Cape Town.Vidua nestlings imprint on their hosts, altering their mating and host preferences based on early life experiences. These preferences strongly influence the host environment in which their offspring grow up, and therefore the evolutionary selection pressures they experience from foster parents. When maintained over multiple generations, these selection pressures generate the astounding host-specific mimetic adaptations observed in the study.
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New Species
| 2,020 |
October 2, 2020
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https://www.sciencedaily.com/releases/2020/10/201002091037.htm
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Woodpeckers' drumming: Conserved meaning despite different structure over the years
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Animal acoustic signals are amazingly diverse. Researchers from the University of Zurich and the University of Saint-Etienne, together with French, American and Dutch collaborators, explored the function and diversification of animal acoustic signals and the mechanisms underlying the evolution of animal communication systems.
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To this end, they used Shannon & Weaver's 'Mathematical Theory of Communication' originally applied to telecommunications in 1949, which has transformed the scientific understanding of animal communication. This theory allows the amount of information in a signal to be quantified. The researchers were the first to use this framework within an evolutionary perspective to explore the biological information encoded in an animal signal.In deciding which biological model to choose, the researchers selected the woodpeckers' drumming as their ideal candidate. This bird family is known for rapidly striking their beaks on tree trunks to communicate. The team combined acoustic analyses of drumming from 92 species of woodpeckers, together with theoretic calculations, evolutionary reconstructions, investigations at the level of ecological communities as well as playback experiments in the field."We wanted to test whether drumming has evolved to enhance species-specific biological information, thereby promoting species recognition," says lead author Maxime Garcia of the UZH Department of Evolutionary Biology and Environmental Studies.Results demonstrate the emergence of new drumming types during woodpeckers evolution. Yet, despite these changes in drumming structure, the amount of biological information about species identity has remained relatively constant for 22 million years. Selection towards increased biological information thus does not seem to represent a major evolutionary driver in this animal communication system. How then can biological information be concretely maintained in nature? Analyses of existing communities around the globe show that ecological arrangements facilitate the efficiency of drumming signals: Communities are composed of only a few species, which distribute their drumming strategies to avoid acoustic overlap. "The responses to different drumming structures seen in our experimental approach show the ability of individuals to recognize their own species based on acoustic cues about species identity found in drumming signals," says Garcia. This way, biological information about species identity can be maintained without necessarily inducing a strong evolutionary pressure on drumming signals.The present study shows that random and unpredictable changes in the structure of communication signals over time can occur while maintaining the signals overall informative potential within and across species. This work leads the way to further investigate the evolution of meaning associated with communicating through multiple communication channels.
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New Species
| 2,020 |
September 25, 2020
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https://www.sciencedaily.com/releases/2020/09/200925113641.htm
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New nemertean species found in Panama represents the first of its genus from the Caribbean
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As Natsumi Hookabe snorkeled around Panama's Bocas del Toro archipelago, during the Smithsonian Tropical Research Institute's Training in Tropical Taxonomy program, she encountered an unusual ribbon worm or nemertean: large and dark colored, with numerous pale spots. It was her first field trip outside of Japan, so she wondered if it was a rare species or just one that she had never seen before.
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Natsumi had been interested in worms since childhood, but when nemerteans were introduced during a university course, she was hooked."I was mesmerized by their body movement while crawling, which involves beautiful muscular waves," she recalled. "This led me to pursue nemertean biology for my bachelor's and master's degrees."She then found out about the Training in Tropical Taxonomy workshop offered by the Smithsonian Tropical Research Institute (STRI) in Panama, and did not have to think for long before flying from Tokyo and plunging into the warm waters of the Caribbean in the Bocas del Toro archipelago.The two-week course, supported by the U.S. National Science Foundation, teaches skills for the identification of understudied marine organisms, including nemerteans. It also offers an opportunity for students to make connections with other researchers from around the world."Hosting the courses has been a really fantastic way, not just to train the next generation of biodiversity researchers, but to also have the Bocas fauna carefully surveyed and identified by experts," said Rachel Collin, STRI staff scientist and director of the Bocas del Toro Research Station. "Over the years this has led to the discovery and description of many new species in Bocas del Toro. For some groups, Bocas has the most documented species for anywhere in the Caribbean."During her stay in Bocas del Toro, Natsumi met Maycol Madrid, a biologist and assistant in Dr. Collin's lab. She quickly noted Maycol's deep knowledge about Japanese culture. In their spare time, they talked about Japanese manga, anime, and games and taught each other Japanese and Spanish words, respectively.When Natsumi collected the unusual-looking nemertean, she knew she wanted to study it further in her lab in Japan, but this required sorting out a few bureaucratic processes. Maycol jumped in and lent his hand in getting the permissions to collect specimens, transportation to Japan, among other tasks.All these efforts paid off: what seemed at first sight like a rare worm to Natsumi, turned out to be a new species of nemertean."Without Maycol's help, my trip would not have been as successful as it actually was," said Natsumi. "I really appreciate his sincere assistance throughout the period of my stay in Bocas."She recently described the new species in the journal Marine Biodiversity, and named it Euborlasia maycoli sp. nov. after Maycol Madrid, as a token of appreciation for all his help. This new Panamanian species became the first Caribbean representative of the genus."For me it was a great surprise that Natsumi decided to name the new species of Euborlasia in my honor," said Maycol. "It fills me with great pleasure, knowing that I was somehow able to help Natsumi in the discovery of this new species."
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New Species
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September 23, 2020
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https://www.sciencedaily.com/releases/2020/09/200923124749.htm
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Tiny worlds reveal fundamental drivers of abundance, diversity
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The natural world is astonishingly complex. After centuries of study, scientists still have much to learn about how all the species in an ecosystem coexist, for example. New research on microbial communities published in
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"What I wanted to know is, sure communities are very complicated, there are many species interacting, but if we try to describe the most important forces shaping this community, what are they?" says author Jacopo Grilli, a biological physicist at the International Center for Theoretical Physics in Trieste, Italy and a former Omidyar Fellow at the Santa Fe Institute in the U.S.Grilli, whose work focuses on understanding complex phenomena by using simple rules, knew that to begin to answer that question, he needed to focus on ecological communities from many different environments, and for which a wealth of data already existed. It's far easier to study a glass of ocean water or a spoonful of soil than a patch of forest, he explains. "Ecology is traditionally a data-poor discipline. But in the case of microbial communities, it's much easier to get a lot of data on these communities, across several conditions," Grilli says. "Microbial communities are everywhere. They are all around us, outside and inside us. So they contribute to many fundamental ecological processes around the world, and they determine in some part our health and well-being. Their impact on our lives and on our planet is immense."In parsing the abundance and diversity of bacteria in a variety of tiny worlds using a simple mathematical model, Grilli's research suggests that environmental variability is the main determinant of whether a species is present or absent in a microbial community, and that environmental change -- such as a change in temperature or nutrients -- is the primary driver of fluctuations in the abundance of a species. "That sort of suggests the players are different -- the species that are in our gut versus the species that are in the ocean are different -- but the forces that shape them are the same," Grilli says.He also identified three key laws that help explain how the number of species in an ecosystem fluctuates over time. These laws can be used to predict a species presence or absence and the diversity in a system.While the size, complexity, and dearth of data for, say, a forest ecosystem makes it difficult to extrapolate the findings to other systems, Grilli says these laws can be used as a starting point for investigations of bigger ecosystems."When we look at these bacterial communities, the number of individuals is huge compared to the forest next to our backyard," he says. For example, the number of bacterial cells in our colon is ten times the number of trees in the world. "So when we understand something about the ecology of bacteria, we are looking at the ecology of something that is at the spatial and temporal scale of our planet. Every hypothesis in the context of micro-communities provides a starting point for other communities. And it's obvious why, in a time when we see a huge decline in biodiversity at the global scale, understanding something more about ecology and in such a large scale is important."Grilli is now building on this work to better understand interactions among microbial species.Grilli adds that while he is the sole author of the paper, the research was informed by input from the many scientists from diverse disciplines he met while he was a fellow at SFI. "If I didn't spend the time at SFI, where I had the opportunity to discuss and collaborate, I don't think this paper would have existed," he says. "It's the result of many conversations and the environment."
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New Species
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September 23, 2020
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https://www.sciencedaily.com/releases/2020/09/200923124555.htm
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Genome duplications as evolutionary adaptation strategy
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Genome duplications play a major role in the development of forms and structures of plant organisms and their changes across long periods of evolution. Heidelberg University biologists under the direction of Prof. Dr Marcus Koch made this discovery in their research of the Brassicaceae family. To determine the scope of the different variations over 30 million years, they analysed all 4,000 species of this plant family and investigated at the genus level their morphological diversity with respect to all their characteristic traits. The results of this research were published in the journal
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The external form of a plant, also known as its morphology, notably depends on environmental factors and their influences. This is true over short time scales of individual development as well as over the long term on an evolutionary scale. "A plant species always embodies only a portion of the possible breadth of morphological variation in evolution, thus allowing related evolutionary lines to be studied as a group for their morphological disparity," stresses Prof. Koch, who leads the Biodiversity and Plant Systematics research group at the Centre for Organismal Studies (COS) of Heidelberg University. The extent of this disparity can be viewed as evolutionary potential for adaptations to altered environments and an associated differentiation.To measure the morphological variation, the researchers first recorded the characteristic traits of the 4,000 Brassicaceae species in a checklist describing the identity and correlations of the species. They then constructed a family tree on genus level from next generation sequencing DNA data to visualise and test the underlying evolutionary dynamics. The tree facilitates the study of complex traits and their development over the course of evolution and places them in the context of other processes and events such as genome duplications or major changes in speciation rates. Genome duplications, that is the multiplication of the whole genome in a cell, describe an exceptional process in land plants to make available additional genetic variability."One surprising result of our study is that there is no key innovation with respect to the morphological characteristics studied. The character traits constantly change and appear to be arbitrarily assembled over and over. The old evolutionary lines make use of the morphological potential in a different way but do not differ from one another in terms of their disparity. In this way, evolution can proceed quickly and divergently," states Marcus Koch.These patterns are associated with genome duplications, which reflect the genetic components, as well as a rapid increase in speciation rates as an expression of selection pressure of past and changing environments. Accordingly, present-day Brassicaceae exhibit more than 40 percent polyploid species, which underwent genome duplications and carry a multiple set of chromosomes. "That means that a species like thale cress, Arabidopsis thaliana, has gone through at least three genome duplications over the course of evolution of the flowering plants in the last 160 million years. Yet this species still has only ten chromosomes because the genomes have to be subsequently stabilised and usually scaled back down over the long term," explains Prof. Koch.The research was conducted mainly in the framework of the DFG priority program "Evolutionary Plant Solutions to Ecological Challenges" (SPP 1529). The data are available in a public access database.
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New Species
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September 16, 2020
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https://www.sciencedaily.com/releases/2020/09/200916154849.htm
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Scientists explaining how diverse species coexist in microbial communities
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Diversity in many biological communities is a sign of an ecosystem in balance. When one species dominates, the entire system can go haywire. For example, the uncontrolled overgrowth of certain oceanic algae species causes toxic red tides that kill fish and other sea life, and sicken humans. On a more individual level, the human gut hosts a large community of different bacteria that is crucial for proper digestion and absorption of nutrients. Disruption of or imbalances in this bacterial community can cause a bloom in the growth of a toxic species, causing nausea, diarrhea and other illnesses. Plainly, there's an urgent need to understand how microbial community diversity is developed and maintained, especially as human activities change our external and internal environments.
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Like all life, microbes require certain nutrients, such as sunlight, sugars or nitrogen sources, to survive and reproduce. Many microbe species' nutrient requirements overlap, putting them in competition with each other. Much effort has been devoted to understanding how this competition influences microbial diversity when nutrients are steadily supplied. However, in nature, it's quite common for the resources to be available only seasonally so that their supply is severely limited at least some of the time. For example, bacteria in the gut that live on sugars might find these abundant right after the human's had a meal, and scarcer the rest of the time. Because each bacterial species is genetically unique, it will have its own particular strategy for using a given nutrient. Species with the most efficient strategies for using the available nutrients experience the best growth."A long-standing question about microbes concerns how so many different microbial species manage to coexist when competing for limited resources," said Ned Wingreen, a professor in Princeton's Department of Molecular Biology and the senior author on a paper in the Sept. 11 issue of the journal Researchers can recreate seasonal nutrient supply in a laboratory by placing bacteria in a container with nutrients, letting them grow, then taking a small sample and moving it to a new container of nutrients -- a process called "serial dilution." Over time, the relative abundance of different species in the culture will change according to the nutrients available and the species' nutrient use strategies. By performing repeated rounds of serial dilution, scientists can observe the effects of seasonally supplied nutrients on community diversity.Of course, it would be impractical to examine all possible combinations of bacteria, nutrients and nutrient utilization strategies using this method. Instead, associate research scholar Amir Erez and graduate student Jaime Lopez, co-authors on the paper and members of Wingreen's lab, and their collaborators investigated this question by mathematically modeling serial dilution."In our paper, we develop a general theory of microbial resource competition in a seasonal ecosystem by modeling recurrent nutrient addition and depletion," explained Wingreen.When nutrients are only seasonally available, the modeling uncovered a surprising relationship between species diversity and the amount of nutrients supplied. First, species diversity is high when all nutrients are supplied in very high amounts because growth of all species is equally unlimited at high nutrient levels. Diversity is also high at very low nutrient amounts because growth of all species is restricted under such conditions and no species can gain an advantage."Nutrient-consumption trade-offs in seasonal ecosystems can lead to stable ecosystems that support diversity beyond what is predicted by simpler mathematical models," observed Wingreen.At intermediate nutrient levels, however, species diversity nose-dives because there will always be one species whose ability to use the most abundant nutrient present outstrips that of others. This species, which the authors call the "early bird," gains an early growth advantage the others can never make up for."The early bird species use their earlier access to nutrients to exclude their not-so-early competitors," explains Wingreen. "The early bird is efficient at consuming easily accessible nutrients and uses its early advantage to out-compete competitors for nutrients that are not as easily accessible."The early bird effect crops up even in more elaborate versions of the model that allow species to feed off others' metabolic byproducts, or for members of a dwindling species to be replenished by in-migration of new individuals. But the identity of the early bird, or whether there will even be one, shifts according to the inputs of the model: what nutrients are present and in what amounts; how often nutrients are supplied; and which species are present and what their strategies are. Whenever it appears, the early bird influences how the ecosystem responds to nutrient changes."Ecologists have long sought a universal relationship between biodiversity and the amount of nutrient supplied to a community. The existence of this universal relationship is not supported by our model," says Wingreen."This is an important paper," says Alvaro Sanchez, a professor in ecology and evolutionary biology at Yale University and an editor at
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New Species
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September 10, 2020
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https://www.sciencedaily.com/releases/2020/09/200910090112.htm
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Over a century later, the mystery of the Alfred Wallace's butterfly is solved
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An over a century-long mystery has been surrounding the Taiwanese butterfly fauna ever since the "father of zoogeography" Alfred Russel Wallace, in collaboration with Frederic Moore, authored a landmark paper in 1866: the first to study the lepidopterans of the island.
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Back then, in their study, Moore dealt with the moths portion and Wallace investigated the butterflies. Together, they reported 139 species, comprising 93 nocturnal 46 diurnal species, respectively. Of the latter, five species were described as new to science. Even though the correct placements of four out of those five butterflies in question have been verified a number of times since 1886, one of those butterflies: Lycaena nisa, would never be re-examined until very recently.In a modern-day research project on Taiwanese butterflies, scientists retrieved the original type specimen from the Wallace collection at The History Museum of London, UK. Having also examined historical specimens housed at the Taiwan Agricultural Research Institute, in addition to newly collected butterflies from Australia and Hong Kong, Dr Yu-Feng Hsu of the National Taiwan Normal University finally resolved the identity of the mysterious Alfred Wallace's butterfly: it is now going by the name Famegana nisa (comb. nov.), while two other species names (Despite having made entomologists scratch their heads for over a century, in the wild, the Wallace's butterfly is good at standing out. As long as one knows what else lives in the open grassy habitats around, of course. Commonly known as 'Grass Blue', 'Small Grass Blue' or 'Black-spotted Grass Blue', the butterfly can be easily distinguished amongst the other local species by its uniformly grayish white undersides of the wings, combined with obscure submarginal bands and a single prominent black spot on the hindwing.However, the species demonstrates high seasonal variability, meaning that individuals reared in the dry season have a reduced black spot, darker ground colour on wing undersides and more distinct submarginal bands in comparison to specimens from the wet season. This is why Dr Yu-Feng Hsu notes that it's perhaps unnecessary to split the species into subspecies even though there have been up to four already recognised.Alfred Russel Wallace, a British naturalist, explorer, geographer, anthropologist, biologist and illustrator, was a contemporary of Charles Darwin, and also worked on the debates within evolutionary theory, including natural selection. He also authored the famed book Darwinism in 1889, which explained and defended natural selection.While Darwin and Wallace did exchange ideas, often challenging each other's conclusions, they worked out the idea of natural selection each on their own. In his part, Wallace insisted that there was indeed a strong reason why a certain species would evolve. Unlike Darwin, Wallace argued that rather than a random natural process, evolution was occurring to maintain a species' fitness to the specificity of its environment. Wallace was also one of the first prominent scientists to voice concerns about the environmental impact of human activity.
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New Species
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September 8, 2020
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https://www.sciencedaily.com/releases/2020/09/200908200524.htm
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New fossil ape discovered in India
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A 13-million-year-old fossil unearthed in northern India comes from a newly discovered ape, the earliest known ancestor of the modern-day gibbon. The discovery by Christopher C. Gilbert, Hunter College, fills a major void in the ape fossil record and provides important new evidence about when the ancestors of today's gibbon migrated to Asia from Africa.
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The findings have been published in the article "New Middle Miocene ape (primates: Hylobatidae) from Ramnagar, India fills major gaps in the hominoid fossil record" in the The fossil, a complete lower molar, belongs to a previously unknown genus and species (Kapi ramnagarensis) and represents the first new fossil ape species discovered at the famous fossil site of Ramnagar, India, in nearly a century.Gilbert's find was serendipitous. Gilbert and team members Chris Campisano, Biren Patel, Rajeev Patnaik, and Premjit Singh were climbing a small hill in an area where a fossil primate jaw had been found the year before. While pausing for a short rest, Gilbert spotted something shiny in a small pile of dirt on the ground, so he dug it out and quickly realized he'd found something special."We knew immediately it was a primate tooth, but it did not look like the tooth of any of the primates previously found in the area," he said. "From the shape and size of the molar, our initial guess was that it might be from a gibbon ancestor, but that seemed too good to be true, given that the fossil record of lesser apes is virtually nonexistent. There are other primate species known during that time, and no gibbon fossils have previously been found anywhere near Ramnagar. So we knew we would have to do our homework to figure out exactly what this little fossil was."Since the fossil's discovery in 2015, years of study, analysis, and comparison were conducted to verify that the tooth belongs to a new species, as well as to accurately determine its place in the ape family tree. The molar was photographed and CT-scanned, and comparative samples of living and extinct ape teeth were examined to highlight important similarities and differences in dental anatomy."What we found was quite compelling and undeniably pointed to the close affinities of the 13-million-year-old tooth with gibbons," said Alejandra Ortiz, who is part of the research team. "Even if, for now, we only have one tooth, and thus, we need to be cautious, this is a unique discovery. It pushes back the oldest known fossil record of gibbons by at least five million years, providing a much-needed glimpse into the early stages of their evolutionary history."In addition to determining that the new ape represents the earliest known fossil gibbon, the age of the fossil, around 13 million years old, is contemporaneous with well-known great ape fossils, providing evidence that the migration of great apes, including orangutan ancestors, and lesser apes from Africa to Asia happened around the same time and through the same places."I found the biogeographic component to be really interesting," said Chris Campisano. "Today, gibbons and orangutans can both be found in Sumatra and Borneo in Southeast Asia, and the oldest fossil apes are from Africa. Knowing that gibbon and orangutan ancestors existed in the same spot together in northern India 13 million years ago, and may have a similar migration history across Asia, is pretty cool."The research team plans to continue research at Ramnagar, having recently received a grant from the National Science Foundation to continue their ongoing search for ape fossils.Article coauthors include Chris Gilbert Anthropology, Hunter College, and the Graduate Center (both of the City University of New York); Alejandra Ortiz, New York University and the Institute of Human Origins, Arizona State University; Kelsey D. Pugh, American Museum of Natural History; Christopher J. Campisano, Institute of Human Origins and the School of Human Evolution and Social Change, Arizona State University; Biren A. Patel, Keck School of Medicine and the Department of Biological Sciences, University of Southern California; Ningthoujam Premjit Singh, Department of Geology, Panjab University; John G. Fleagle, Department of Anatomical Sciences, Stony Brook University; and Rajeev Patnaik, Department of Geology, Panjab University.This research at Ramnagar was funded by the Leakey Foundation, the PSC-CUNY faculty award program, Hunter College, the AAPA professional development program, the University of Southern California, the Institute of Human Origins (Arizona State University), and the National Science Foundation. Indian colleagues are further supported by the Indian Ministry of Earth Sciences and Science and Engineering Research Board.
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New Species
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September 3, 2020
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https://www.sciencedaily.com/releases/2020/09/200903095641.htm
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New species of freshwater crustacea found in the hottest place on Earth
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A new species of freshwater Crustacea has been discovered during an expedition of the desert Lut, known as the hottest place on Earth.
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The newly identified species belongs to the genus Phallocryptus of which only four species were previously known from different arid and semiarid regions.Dr Hossein Rajaei from the Stuttgart State Museum of Natural History and Dr Alexander V Rudov from Tehran University made the discovery during an expedition of Lut to better understand the desert's ecology, biodiversity, geomorphology and paleontology.Further scientific examinations of the specimens by co-author Dr Martin Schwentner, Crustacea specialist from the Natural History Museum of Vienna, stated that they belong to a new species of freshwater Crustacea.Publishing their findings in Dr Rajaei, an entomologist from State Museum of Natural History Stuttgart, who actually found the species in a small seasonal lake in southern part of the desert says the discovery is "sensational.""During an expedition to such an extreme place you are always on alert, in particular when finding water. Discovering crustaceans in this otherwise hot and dry environment was really sensational."The team's study explains how Phallocryptus fahimii differs in its overall morphology and its genetics from all other known Phallocryptus species.Dr Schwentner, who has worked with similar crustaceans from the Australian deserts in the past, adds: "These Crustaceans are able to survive for decades in the dried-out sediment and will hatch in an upcoming wet season, when the aquatic habitat refills. They are perfectly adapted to live in deserts environments. Their ability to survive even in the Lut desert highlights their resilience."The Lut desert -- also known as Dasht-e Lut -- is the second largest desert in Iran.Located between 33° and 28° parallels and with its 51,800 km2 larger than Switzerland, this desert holds the current record for the highest ever-recorded surface temperature. Based on 2006 satellite measurements, the NASA reported a record surface temperature of 70.7°C, which more recently has been increased to even 80.3°C. Dark pebbles that heat up are one of the causes of these record temperatures. Mean daily temperatures range from -2.6°C in winter to 50.4°C in summer with annual precipitation not exceeding 30 mm per year.Almost deprived of vegetation, the Lut desert harbors a diverse animal life, but no permanent aquatic biotops (such as ponds).After rain falls, non-permanent astatic water bodies are filled including the Rud-e-Shur river from north-western Lut.Here a diverse community of Archaea has been described but aquatic life in the Lut remains highly limited, which makes this find particularly rare.
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New Species
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August 24, 2020
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https://www.sciencedaily.com/releases/2020/08/200824092008.htm
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New species of Cretaceous brittle star named in honor of Nightwish vocalist
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Palaeontologists from the Natural History Museums in Luxembourg and Maastricht have discovered a previously unknown species of brittle star that lived in the shallow, warm sea which covered parts of the present-day Netherlands at the end of the Dinosaur Era. The starfish-like creature was unearthed more than 20 years ago but has only now been identified as new to science. The name of the new fossil pays tribute to Dutch metal vocalist Floor Jansen, in recognition of the mutual inspiration between science and music.
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Like so many exciting discoveries, the new fossil species had long passed unnoticed. It was a stroke of luck when a fossil collector noted the fossil of a tiny, starfish-like creature during one of his excursions to the world-famous ENCI HeidelbergCement company quarry near the Dutch city of Maastricht. The specimen was much smaller than other brittle-star fossils occasionally found at the same locality and thus much less likely to be collected. Dr John Jagt, palaeontologist at the Natural History Museum in Maastricht, soon identified the specimen as a long-spined brittle-star. "I reckoned the specimen belonged to a group of brittle-stars that is particularly rare in the fossil record but its true identity remained puzzling with the information at hand," Jagt explains. "When examining microfossils extracted from the same rocks that yielded the brittle-star fossil, I noticed microscopic skeletal fragments that seemed to belong to the same species," he continues.20 years later, Jagt was proved right when Dr Ben Thuy and Dr Lea Numberger, palaeontologists at the Natural History Museum in Luxembourg, examined the brittle-star fossils from Maastricht from a different angle, taking into account the latest progress of knowledge in the field. "We were incredibly lucky to have both microscopic skeletal remains and a complete fossil skeleton of the same brittle-star species," Thuy highlights. "This provided an exceptionally complete picture of the species" Numberger continues. That the species turned out to be new to science was exciting in itself but there was more: "The new brittle star must have lived in a shallow, warm sea while its living relatives are found in the deep sea. This shows that there was a major shift in distribution over the past million years," Thuy explains.The experts were even able to gain insights into the mode of life of the new species. "Because the fossil individual was found wrapped around the stalk of a sea lily, we assume that the species lived with and probably even clung to these flower-like echinoderms," Jagt remarks. Interactions or associations between species are only rarely preserved in the fossil record. When scientists discover a new species, they have the privilege to name it. Often, species names refer to a locality or a specific character. Some also honour other experts in the field. In the case of the Maastricht brittle star, Jagt, Thuy and Numberger decided to combine their passions for fossils and heavy metal music and paid tribute to Dutch metal vocalist Floor Jansen and her band Nightwish. "Rock music and fossils are a perfect match. They have been inspiring each other for a long time" Numberger explains.The new fossil, Ophiomitrella floorae, is in excellent company, as can be experienced in the travelling exhibition "Rock Fossils on Tour," celebrating fossils named after rock bands and musicians like Kalloprion kilmisteri, an ancient worm honouring Motörhead's Ian "Lemmy" Kilmister, and currently on display (until January 3, 2021) at the Natural History Museum in Maastricht.
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New Species
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August 13, 2020
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https://www.sciencedaily.com/releases/2020/08/200813105946.htm
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Strianassa lerayi anker, new shrimp species from Panama's Coiba national park
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John Steinbeck wrote Log From the Sea of Cortez in 1951, his chronicle of an expedition with marine biologist Ed Ricketts along the coast of California and Mexico. Ricketts named several of the many new marine animals they found after Steinbeck, his friend and patron of the expedition. On a similar expedition in February 2019 to Panama's Coiba National Park in the Pacific Ocean, marine biologists from the Smithsonian Tropical Research Institute (STRI) discovered several new, undescribed animals, genera and species never seen or photographed before, nearly every day.
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Matthieu Leray, post-doctoral fellow at STRI, invited two zoologists, STRI Research Associate Arthur Anker and Paulo Pachelle, to join the expedition to Coiba. Both are based in Brazil and specialize in the identification of decapod crustaceans, such as shrimps, crabs, hermit-crabs and lobsters.Anker named one of the new genus and species of mud-shrimps in the family "Arthur was able to describe three new genera and one new species of shrimp based on a week of collecting in Coiba National Park," Leray said. "This is a phenomenal contribution to our knowledge of just one group of organisms. We are in the process of identifying what we found and will announce more new species soon."The team found the only known specimen of this new mud shrimp under a rock while snorkeling in shallow waters in the archipelago.The site of their discovery is only a few kilometers away from the newest STRI research station on Coibita Island. Anker and Pachelle also found a small clam with a highly reduced shell, a huge mantle with papillae and long extensible foot, popularly known as a "yoyo clam." These unusually mobile and active bivalve mollusks live in symbiosis with burrowing mantis shrimps. This is the first known yoyo clam from the eastern Pacific and represents a new species of the genus Divariscintilla. Amazingly, the site where they found a single specimen of the clam is the boat "parking area" of the STRI station at Coibita. The species is now being studied by a Japanese team, all specialists in this taxonomically difficult group of mollusks."We are thrilled by the potential of our newest research station on Coibita," said Oris Sanjur, acting director at STRI. "The tropical eastern Pacific is still largely unexplored by specialists with knowledge of these, less obvious, organisms. At our Bocas del Toro Research Station, the director, Rachel Collin, began a program called Training in Tropical Taxonomy that brings specialists from around the world to Panama. In the past 10 years, they have identified more than 75 new species, many of which are only found in Panama. We hope to foster similar programs based at the Coibita Station."The expedition was funded by STRI and the Gordon and Betty Moore Foundation as part of a much larger project called The Role of Microbes in Shaping Tropical Ecosystems. The aim of that project is to better understand how microbial communities evolve by comparing the microbes on "sister species," animals that were separated when the rise of the Isthmus of Panama divided one ocean into the Atlantic and Pacific, millions of years ago. Scientists want to better understand how closely associated microbes are with their hosts and the importance of environment and other factors in determining their presence.The researchers thank the Coiba National Park staff and Panama's Ministry of the Environment, MiAmbiente, for the collection permits that make new discoveries like this possible."We collected In addition to The researchers also add Leslibetaeus coibita, also a new genus and species, which was described by Anker and collaborators in 2005 when Anker was a post-doctoral fellow at STRI. The species name indicates that it was collected in Coibita, right in front of the station."New microbes are a dime a dozen," said Bill Wcislo, senior staff scientist and microbiome project leader along with Jonathon Eisen at the University of California Davis. "But several new host genera in a short time collecting in just one group of invertebrates. That is something remarkable. And a new species named for STRI and for Matt Leray is spectacular! It is just the tip of the iceberg for the Smithsonian's newest crown jewel."
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New Species
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August 11, 2020
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https://www.sciencedaily.com/releases/2020/08/200811204537.htm
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New species of dinosaur discovered on Isle of Wight
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A new study by Palaeontologists at the University of Southampton suggests four bones recently found on the Isle of Wight belong to new species of theropod dinosaur, the group that includes Tyrannosaurus rex and modern-day birds.
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The dinosaur lived in the Cretaceous period 115 million years ago and is estimated to have been up to four metres long.The bones were discovered on the foreshore at Shanklin last year and are from the neck, back and tail of the new dinosaur, which has been named Vectaerovenator inopinatus.The name refers to the large air spaces in some of the bones, one of the traits that helped the scientists identify its theropod origins. These air sacs, also seen in modern birds, were extensions of the lung, and it is likely they helped fuel an efficient breathing system while also making the skeleton lighter.The fossils were found over a period of weeks in 2019 in three separate discoveries, two by individuals and one by a family group, who all handed in their finds to the nearby Dinosaur Isle Museum at Sandown.The scientific study has confirmed the fossils are very likely to be from the same individual dinosaur, with the exact location and timing of the finds adding to this belief.Robin Ward, a regular fossil hunter from Stratford-upon-Avon, was with his family visiting the Isle of Wight when they made their discovery. He said: "The joy of finding the bones we discovered was absolutely fantastic. I thought they were special and so took them along when we visited Dinosaur Isle Museum. They immediately knew these were something rare and asked if we could donate them to the museum to be fully researched."James Lockyer, from Spalding, Lincolnshire was also visiting the Island when he found another of the bones. Also a regular fossil hunter, he said: "It looked different from marine reptile vertebrae I have come across in the past. I was searching a spot at Shanklin and had been told and read that I wouldn't find much there. However, I always make sure I search the areas others do not, and on this occasion it paid off."Paul Farrell, from Ryde, Isle of Wight, added: "I was walking along the beach, kicking stones and came across what looked like a bone from a dinosaur. I was really shocked to find out it could be a new species."After studying the four vertebrae, paleontologists from the University of Southampton confirmed that the bones are likely to belong to a genus of dinosaur previously unknown to science. Their findings will be published in the journal Chris Barker, a PhD student at the university who led the study, said: "We were struck by just how hollow this animal was -- it's riddled with air spaces. Parts of its skeleton must have been rather delicate."The record of theropod dinosaurs from the 'mid' Cretaceous period in Europe isn't that great, so it's been really exciting to be able to increase our understanding of the diversity of dinosaur species from this time."You don't usually find dinosaurs in the deposits at Shanklin as they were laid down in a marine habitat. You're much more likely to find fossil oysters or drift wood, so this is a rare find indeed."It is likely that the Vectaerovenator lived in an area just north of where its remains were found, with the carcass having washed out into the shallow sea nearby.Chris Barker added: "Although we have enough material to be able to determine the general type of dinosaur, we'd ideally like to find more to refine our analysis. We are very grateful for the donation of these fossils to science and for the important role that citizen science can play in palaeontology."The Isle of Wight is renowned as one of the top locations for dinosaur remains in Europe, and the new Vectaerovenator fossils will now go on display at the Dinosaur Isle Museum at Sandown, which houses an internationally important collection.Museum curator, Dr Martin Munt, said: "This remarkable discovery of connected fossils by three different individuals and groups will add to the extensive collection we have and it's great we can now confirm their significance and put them on display for the public to marvel at."We continue to undertake public field trips from the museum and would encourage anyone who finds unusual fossils to bring them in so we can take a closer look. However, fossil hunters should remember to stick to the foreshore, and avoid going near the cliffs which are among the most unstable on the Island."Isle of Wight Council Cabinet member for environment and heritage, Councillor John Hobart, said: "This is yet another terrific fossil find on the Island which sheds light on our prehistoric past -- all the more so that it is an entirely new species. It will add to the many amazing items on display at the museum."
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New Species
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August 10, 2020
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https://www.sciencedaily.com/releases/2020/08/200810183902.htm
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How boundaries become bridges in evolution
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There's a paradox within the theory of evolution: The life forms that exist today are here because they were able to change when past environments disappeared. Yet, organisms evolve to fit into specific environmental niches.
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"Ever-increasing specialization and precision should be an evolutionary dead end, but that is not the case. How the ability to fit precisely into a current setting is reconciled with the ability to change is the most fundamental question in evolutionary biology," says Alex Badyaev, a University of Arizona professor of ecology and evolutionary biology .Badyaev is co-author of a paper published in There are two general possible solutions, according to Badyaev. First, the mechanisms that enable organisms to fit well into their current environment and the mechanisms that enable change in adaptations are distinct -- the latter are suppressed as organisms fit better and better into their current setting and activated only when the environment changes. The second is that the mechanisms that make organisms fit into current environments are themselves modified during evolution."Distinguishing between these possibilities is challenging because in evolutionary biology we necessarily study processes that occurred in the past, the events that we missed," he said. "So, instead, we infer what we missed from comparisons of species that exist today. Although this approach can tell us how well the current organisms fit into their current environment, it cannot tell us how they got here."Ultimately, the first scenario was supported by the researchers' work. The mechanisms that make organisms locally fit and those responsible for change are distinct and occur sequentially in evolution.Badyaev and his team aimed to directly observe adaptation to new environments in action while specifically paying attention to the mechanisms involved. The opportunity was provided by the house finch, a ubiquitous Sonoran Desert bird that over the last century has spread throughout most of North America and now occupies the largest ecological ranges of any living bird species.Birds color themselves by eating and integrating pigmented molecules called carotenoids into their feathers."Carotenoids are large molecules, and stuffing them into growing feather is a messy process, resulting in all kinds of structural modifications and aberrations to feathers," Badyaev said. "This presents a unique opportunity to study how well-characterized developmental mechanisms that produce an intricate feather co-evolve with unpredictable external inputs needed to color them."In feathers where structural integrity is essential, such as in temperature-regulating down or flight feathers, mechanisms evolve that buffer feather growth from incorporating carotenoids. For this reason, flight feathers or down feathers are almost never colorful in any bird species. On the opposite end of spectrum, ornamental feathers benefit from being colorful and evolve mechanisms that modify their structure to enable greater incorporation of carotenoids and to enhance their presentation.The authors took advantage of this diversity and studied how this array of mechanisms -- from complete buffering of carotenoids to fully embracing them -- actually evolves.The sources of carotenoid pigments differ across the house finch's huge range. In native desert populations, finches obtain their pigments from cactus pollen and fruits, while in urban populations they get them from newly introduced plant species and bird feeders. In northern populations, they incorporate the pigments from grass seeds, buds and berries."As expected, within each of these locations finches have evolved precise adaptations to incorporate diverse local carotenoids into their feathers," Badyaev said. But the unique aspect of this study is that "we knew the colonization routes of these birds, which enabled us to observe how they modify these adaptations as they move from one location to the next over the last century."This approach not only allowed the team to directly study the process of evolution but also enabled them to study repeated evolution in the wild, because birds evolved distinct local adaptations in parallel from known starting points as they spread through the continent."We got to replay the tape of evolution of this adaptation, instead of deducing the process from the outcome," Badyaev said.The team established 45 study populations along colonization routes that the species took from its native southern Arizona to the northwestern United States. They also explored how species changed within regions, such as between Arizona desert populations and urban populations on the University of Arizona campus and in Tucson. In all of these populations they examined microscopic structure and complete carotenoid composition in thousands upon thousands of feather samples. The unprecedented scale and depth of the study -- believed to be the largest of its kind in a wild bird species -- led to two discoveries.First, evolution proceeded by remarkably similar sequences from widely diverse starting points. Unfamiliar local carotenoids exerted major modifications in developing feathers at first, but the longer birds persisted in a region and the more familiar they became with local carotenoids, the better there were able to incorporate them into their feathers, eventually evolving precise local adaptations.Second, and most importantly, although carotenoids and their mixtures differed strongly between locations as distinct as deserts and northern evergreen forests, the mechanisms behind their incorporation into growing feathers were remarkably uniform and not specific to biochemical properties of individual carotenoid compounds. Instead, in all populations, evolution resulted from changes in mechanisms that buffered previous local adaptation from external stressors. These general stress-buffering mechanisms -- what Badyaev called "the guardians of local adaptations" -- had to be recruited to allow evolution of new adaptations.In other words, "the boundaries of current adaptations become bridges between successive adaptions in evolution," Badyaev said.The next step for the authors is to study the origin of molecular and developmental mechanisms they implicated in stress-buffering processes in evolution.
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New Species
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August 7, 2020
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https://www.sciencedaily.com/releases/2020/08/200807111942.htm
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Updating Turing's model of pattern formation
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In 1952, Alan Turing published a study which described mathematically how systems composed of many living organisms can form rich and diverse arrays of orderly patterns. He proposed that this 'self-organisation' arises from instabilities in un-patterned systems, which can form as different species jostle for space and resources. So far, however, researchers have struggled to reproduce Turing patterns in laboratory conditions, raising serious doubts about its applicability. In a new study published in EPJ B, researchers led by Malbor Asllani at the University of Limerick, Ireland, have revisited Turing's theory to prove mathematically how instabilities can occur through simple reactions, and in widely varied environmental conditions.
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The team's results could help biologists to better understand the origins of many ordered structures in nature, from spots and stripes on animal coats, to clusters of vegetation in arid environments. In Turing's original model, he introduced two diffusing chemical species to different points on a closed ring of cells. As they diffused across adjacent cells, these species 'competed' with each other as they interacted; eventually organising to form patterns. This pattern formation depended on the fact that the symmetry during this process could be broken to different degrees, depending on the ratio between the diffusion speeds of each species; a mechanism now named the 'Turing instability.' However, a significant drawback of Turing's mechanism was that it relied on the unrealistic assumption that many chemicals diffuse at different paces.Through their calculations, Asllani's team showed that in sufficiently large rings of cells, where diffusion asymmetry causes both species to travel in the same direction, the instabilities which generate ordered patterns will always arise -- even when competing chemicals diffuse at the same rate. Once formed, the patterns will either remain stationary, or propagate steadily around the ring as waves. The team's result addresses one of Turing's key concerns about his own theory, and is an important step forward in our understanding of the innate drive for living systems to organise themselves.
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New Species
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August 5, 2020
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https://www.sciencedaily.com/releases/2020/08/200805124056.htm
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New Guinea has the world's richest island flora
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Almost 20 times the size of Switzerland, New Guinea is the world's largest tropical island. It features a complex mosaic of ecosystems ? from lowland jungles to high-elevation grasslands with peaks higher than Mont Blanc. Botanists have long known that this mega-diverse wilderness area is home to a large number of plant species. Efforts to identify and name thousands of plants collected in New Guinea and archived in herbaria all over the world have been ongoing since the 17th century.
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However, since researchers have worked mostly independently from each other, a great uncertainty remains as to the exact number of plant species, with conflicting estimates ranging from 9,000 to 25,000. "Compared to other areas like Amazonia, for which plant checklists were recently published, New Guinea remained the 'Last Unknown'," says Rodrigo Cámara-Leret, a postdoctoral researcher in the lab of Prof. Jordi Bascompte in the UZH Department of Evolutionary Biology and Environmental Studies. Under his lead, 99 scientists from 56 institutions and 19 countries have now built the first expert-verified checklist for the 13,634 vascular plant species of New Guinea and its surrounding islands.The researchers began their large-scale collaborative effort by compiling a list of plant names from online catalogues, institutional repositories and datasets curated by taxonomists. After standardizing the scientific names, 99 experts on New Guinea flora checked almost 25,000 species names derived from over 700,000 individual specimens. For this, they reviewed the list of original names in their plant family of expertise and assessed whether these names were correctly assigned in the online platforms. Finally, an independent comparison was performed between the list accepted by experts and a list contained in Plants of the World Online for New Guinea.The resulting checklist contains 13,634 plants, demonstrating that New Guinea has the world's richest island flora ? with about 20% more species than Madagascar or Borneo. By far the most species-rich family are the orchids and almost a third of the species are trees. One particularly remarkable finding is that 68% of the plants are endemic ? they are only found in the region. "Such high endemic species richness is unmatched in tropical Asia," says Cámara-Leret, "It means that Indonesia and Papua New Guinea, the two states into which the island is divided, have a unique responsibility for the survival of this irreplaceable biodiversity."The new authoritative checklist will improve the accuracy of biogeographic and ecological studies, help focus DNA sequencing on species-rich groups with high endemism, and facilitate the discovery of more species by taxonomists. Thousands of specimens remain unidentified in the collections and many unknown species have yet to be discovered in the wild. "We estimate that in the next 50 years, 3,000 to 4,000 species will be added," says Michael Kessler, co-author of the study and scientific curator of the Botanical Garden of the University of Zurich. These efforts will be important for conservation planning and modelling the impact of changes in climate and land use.The collaboration also underscores that expert knowledge is still essential in the digital era ? reliance on online platforms alone would have erroneously inflated species counts by one fifth. However, many of the New Guinea plants experts are already or soon to be retired, and almost half of them are non-residents. The researchers therefore advocate building a critical mass of resident plant taxonomists.Policy-wise, the study shows that long-term institutional and financial support is critical if significant advances are to be made over the next decades. "Our work demonstrates that international collaborative efforts using verified digital data can rapidly synthesize biodiversity information. This can serve as a model for accelerating research in other hyper-diverse areas such as Borneo," says Cámara-Leret. "Such initiatives pave the way for the grand challenge of conserving the richest island flora of the world."
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New Species
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August 4, 2020
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https://www.sciencedaily.com/releases/2020/08/200804100200.htm
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A 40-year journey leads to a new truffle species
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As a first-year graduate student studying truffle ecology at Oregon State University, Dan Luoma attended a scientific meeting in 1981 on Orcas Island in Washington. Having recently learned how to search for truffles, he went out one day of the meeting looking for the prized fungi and found a collection.
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He brought them back to Oregon State and showed them to his mentor James Trappe, who confirmed the collection was of an undescribed species. Trappe added it to the university's collection. Then it sat there.Almost four decades later, with the help of new scientific technologies, Trappe and several other scientists confirmed that the truffle is unique. They recently published their findings in the journal "This truffle in 1981 was among the first truffles I ever found," Luoma said. "To have it named in my honor the year I retired completes the circle for me. It's a wonderful way to celebrate retirement."Some truffle species are highly prized for culinary purposes because of their distinct flavor. These species, which are black, white or brown, are hard to find and exist in limited geographic areas, meaning they command high prices.Oregon and the Pacific Northwest are home to several of those prized species, making the region one of the world's hot spots for truffle hunting. The species discovered by Luoma, though, is a red truffle, which doesn't have the distinct flavor sought by chefs and cooks.While the culinary use of truffles and the thrill of searching for them gets a lot of attention, they and other fungi are important for the health of forests. They provide nutrients to plants and can also help plants withstand drought.Luoma studied the ecology of truffles and fungi while earning his doctorate from Oregon State in 1988 and until earlier this year worked as a researcher at the university.Several graduate students who worked with him during his early years planned to name the truffle species he found on Orcas Island in honor of Luoma, but they graduated before doing so.Then about 10 years ago Trappe, now Luoma's colleague, searched the Oregon State truffle collections, the largest in the world with about 50,000 collections, looking for truffles similar to the one Luoma found on Orcas Island. Trappe found three.Joyce Eberhart, a truffle researcher at Oregon State and Luoma's wife, and Greg Bonito, an assistant professor at Michigan State University, studied the DNA of those three and determined they were the same species as the Orcas Island truffle.Those three were all found in Oregon -- one each in Benton (found in 1962), Clackamas (1995) and Jackson (2012) counties. While the Benton County specimen was found before Luoma dug up the Orcas Island one, it was never fully described until Trappe noticed the similarities between the two. Now the known distribution of the new species extends from southwestern Oregon to northwestern Washington.Carolina Piña Páez, a doctoral student at Oregon State who also does truffle research, provided the final piece by documenting the microscopic structures inside the truffle with photos, confirming that the spores and outer layers were that of a unique species.Trappe, who has studied truffles for more than 60 years and has discovered 230 new truffle species, still gets excited about a new species, such as this one named after Luoma."Many dozens of professional and amateur mycologists have sought truffles in western Oregon for over 100 years, but only these four collections of Luoma's truffle have been found. Each of those seems to be quite local in distribution, indicating that it's a very rare fungus," Trappe said.
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New Species
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August 3, 2020
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https://www.sciencedaily.com/releases/2020/08/200803105223.htm
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New species of fungus sticking out of beetles
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A major comprehensive study on
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Having surveyed arthropod fauna using pitfall traps and an illuminated white screen at night, and with the help of a network of entomologists, Dr. Danny Haelewaters (Purdue University, University of South Bohemia and Ghent University) and Dr. André De Kesel (Botanic Garden Meise) provide identification details about a total of 140 fungal species. The list includes nine species that are reported for the first time for either of the two countries and two newly described species.Interestingly, one of the novel fungi was described during the 2020 global quarantine period, imposed to curb the COVID-19 pandemic. This prompted the researchers to dedicate the newly discovered species to this extraordinary time. In the annals of science, the species will be going by the name of In their study, the scientists hypothesize that, because of their invasive nature, these haustorial parasites maintain close interactions with their hosts in a process referred to as an "evolutionary arms race." This means that whenever the host evolves a defence mechanism against the fungus, the parasite promptly evolves in its own turn, and adapts accordingly. Eventually, specialization leads to the evolution of new species.The present study compiles all available data from Belgium and the Netherlands and serves as an appropriate starting point for an updated checklist of thallus-forming fungi in the class Laboulbeniomycetes found across Europe. Such a checklist is an ongoing project meant to summarize decades of research and will undoubtedly continue to uncover significant fungal diversity. The last update of this piece of knowledge dates back to 1991.
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New Species
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July 27, 2020
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https://www.sciencedaily.com/releases/2020/07/200727114743.htm
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Unparalleled inventory of the human gut ecosystem
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An international team of scientists has collated all known bacterial genomes from the human gut microbiome into a single large database. Their work, published in
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This project was led by EMBL's European Bioinformatics Institute (EMBL-EBI) and included collaborators from the Wellcome Sanger Institute, the University of Trento, the Gladstone Institutes, and the US Department of Energy Joint Genome Institute.Bacteria coat the human body, inside and out. They produce proteins that affect our digestion, our health, and our susceptibility to diseases. They are so prevalent that the body is estimated to contain more cells in its microbiome -- the bacteria, fungi, and other microbes -- than it has human cells.To understand the role that bacterial species play in human biology, scientists usually isolate and culture them in the lab before they sequence their DNA. However, many bacteria thrive in conditions that are not yet reproducible in a laboratory setting.To obtain information on such species, researchers take another approach: they collect a single sample from the environment -- in this case, the human gut -- and sequence the DNA from the whole sample. They then use computational methods to reconstruct the individual genomes of thousands of species from that single sample. This method, called metagenomics, offers a powerful alternative to isolating and sequencing the DNA of individual species."Last year, three independent teams, including ours, reconstructed thousands of gut microbiome genomes. The big questions were whether these teams had comparable results, and whether we could pool them into a comprehensive inventory," says Rob Finn, Team Leader at EMBL-EBI.The scientists have now compiled 200,000 genomes and 170 million protein sequences from more than 4 600 bacterial species in the human gut. Their new databases, the Unified Human Gastrointestinal Genome collection and the Unified Gastrointestinal Protein catalogue, reveal the tremendous diversity in our guts and pave the way for further microbiome research."This immense catalogue is a landmark in microbiome research, and will be an invaluable resource for scientists to start studying and hopefully understanding the role of each bacterial species in the human gut ecosystem," explains Nicola Segata, Principal Investigator at the University of Trento.The project revealed that more than 70% of the detected bacterial species had never been cultured in the lab -- their activity in the body remains unknown. The largest group of bacteria that falls into that category is the Comantemales, an order of gut bacteria first described in 2019 in a study led by the Bork Group at EMBL Heidelberg."It was a real surprise to see how widespread the Comantemales are. This highlights how little we know about the bacteria in our gut," explains Alexandre Almeida, EMBL-EBI/Sanger Postdoctoral Fellow in the Finn Team. "We hope our catalogue will help bioinformaticians and microbiologists bridge that knowledge gap in the coming years."All the data collected in the Unified Human Gastrointestinal Genome collection and the Unified Human Gastrointestinal Protein catalogue are freely available in MGnify, an EMBL-EBI online resource that allows scientists to analyse their microbial genomic data and make comparisons with existing datasets.The project already has a number of users in the scientific community. As new datasets emerge from research teams around the world, the catalogue might expand to include the microbiomes of other body parts, like the skin or inside the mouth."This catalogue provides a very rich source of information for microbiologists and clinicians. However, we will likely discover many more novel bacterial species in under-represented geographical areas like South America, Asia, and Africa. We still don't know much about the variation in bacterial diversity across different human populations," explains Almeida.
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New Species
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July 20, 2020
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https://www.sciencedaily.com/releases/2020/07/200720103330.htm
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Marine microorganisms: How to survive below the seafloor
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Foraminifera, an ancient and ecologically highly successful group of marine organisms, are found on and below the seafloor. Geobiologists at Ludwig-Maximilians-Universitaet (LMU) in Munich report that several species not only survive, but thrive, in these oxygen-free sediments.
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Foraminifera are unicellular marine organisms that are found on and within seafloor sediments. Most species construct porous mineralized shells and capture prey by extending cytoplasmic filaments though these pores. The group is highly species rich, and their preserved fossilized remains show that they were already present in the oceans at the beginning of the Cambrian Era, 560 million years ago. Their shells have considerable fossilization potential, which explains why they serve as index fossils for the dating of a number of geological eras. Moreover, foraminifera are of great ecological significance -- owing to their contributions to carbon and nitrate cycles, for instance -- and their shells play an important role in the reconstruction of ancient climates. However, despite their well-established status as proxies for environmental conditions, relatively little is known about the biology of contemporary species of foraminifera. LMU geobiologists led by Professor William Orsi of the Department of Earth and Environmental Sciences and the GeoBio Center at LMU, in cooperation with Raphaël Morard and Michal Kucera (Bremen University), have now investigated their metabolism at the molecular level, and found that some species of foraminifera can survive -- and indeed thrive -- in oxygen-free (anoxic) habitats that would be deadly for other eukaryotes. The results of the new study appear in Foraminifera have been previously found in oxygen-poor and even anoxic marine sediments. To learn more about the adaptations that enable them to survive in this inhospitable environment, Orsi and his team examined species sampled from a sediment core recovered from the seafloor off the coast of Namibia. Much of the sediment in this core was anoxic and rich in the toxic gas hydrogen sulfide. Nevertheless, the team found large numbers of Foraminifera at these levels, where they had more than 10 times higher activity compared to the shallower sections with higher levels of oxygen. "Up to now, marine biologists have assumed that, under such conditions, Foraminifera manage to survive on the seafloor and die when they are buried beneath it," says Orsi. "Our results, on the other hand, surprisingly demonstrate that some species of Foraminifera are metabolically more active in anoxic sediments." In other words, it looks as if these organisms are just not eking out a living in these habitats, they appear to be very well adapted to the challenging conditions. Moreover, incubation experiments confirmed their preference for anoxic environments, whereby the activity of the Foraminifera increased up to 40 times in anoxic conditions.Orsi and his colleagues went on to study the metabolic pathways employed by these foraminiferan species by analyzing the messenger RNAs (mRNAs) found in sediment samples. mRNAs are copied from genomic DNA, and encode the instructions for the synthesis of the proteins required for cell function. They therefore allow one to identify the set of genes that are active in the local cell population, and the spectrum of biochemical activities required for cellular metabolism in a given environment. In this case, the analyses revealed that foraminifera make use of a variety of metabolic pathways -- for the fermentation of sugars and amino acids, for instance. In addition, they show that, in addition to capturing and digesting prey, foraminifera in the anoxic zones can exploit soluble organic material as a source of carbon and energy. "Presumably, foraminifera play an important and hitherto overlooked role in anaerobic nutrient cycles," says Orsi. This ability to thrive in such otherwise inhospitable anoxic environments with high levels of toxic hydrogen sulfide gas could be part of the explanation for their ecological success. After all, the group has managed to avoid a number of mass extermination events over the past 500 million years -- many of which were associated with a marked reduction in the availability of oxygen and accumulation of toxic hydrogen sulfide that was responsible for killing off numerous now extinct animal species.
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New Species
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July 15, 2020
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https://www.sciencedaily.com/releases/2020/07/200715142324.htm
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Growth rate of common trilobites
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If you've ever held a trilobite fossil, seen one in a classroom, or walked by one in a store, chances are it was Elrathia kingii, one of the most common and well-recognized trilobites, and collected by the hundreds of thousands in western Utah. But despite the popularity of this species, scientists had not determined how it grew -- from hatchling to juvenile to adult -- until now. New work from the American Museum of Natural History published today in the journal
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"There's quite a big size range among trilobites. Some never got bigger than about a centimeter, while the largest on record is 72 centimeters (28 inches)," said Melanie Hopkins, an associate curator in the Museum's Division of Paleontology and the study's author. "Growth-rate studies like this one can help us tackle some of the big-picture questions: How did some trilobites get so big? What was the environmental context for that? And how did body size evolve over the evolutionary history of the clade?"Trilobites are a group of extinct marine arthropods -- distantly related to the horseshoe crab -- that lived for almost 300 million years. They were incredibly diverse, with more than 20,000 described species. Their fossilized exoskeletons are preserved in sites all over the world, from the United States to China. Like insects, they molted throughout their lifetimes, leaving clues to how they changed during development. But to calculate the species' growth rate, scientists need fossils representing all stages of the animal's life -- and lots of them."There are tons of specimens of Elrathia kingii out there but most of them are adults, and data from exactly where they were collected is inconsistent," Hopkins said. "I needed material that I could collect from as small a section as possible that included a lot of juveniles."So in May 2018, Hopkins spent five days in Utah with a crew consisting of Museum staff and volunteers at a new fossil site said to preserve bucketloads of Elrathia kingii. By the end of the trip, they had collected about 500 specimens -- many of them juveniles, which can be as small as half a millimeter long -- from a section of outcrop just 1.5 meters (about 5 feet) long.Hopkins estimated the growth rate and compared it to previously published data on a different trilobite, Aulacopleura konincki -- the first time two trilobite species have been compared in this way. The two species look very similar and Hopkins found that they also grow in similar ways: for example, the growth of the trunk -- the area immediately below the trilobite's head made up of segments that increase with age -- was controlled by a growth gradient, with those that were younger and closer to the back of the body undergoing faster growth. But while Elrathia kingii was smaller in early development and went through fewer molts before adulthood, it had faster growth rates, ultimately reaching sizes on par with Aulacopleura konincki, the largest of which are about 4 centimeters long.In future studies, Hopkins is planning to add growth-rate data on different, more diverse-looking trilobite species to her models.
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New Species
| 2,020 |
July 8, 2020
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https://www.sciencedaily.com/releases/2020/07/200708105923.htm
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Lefties and righties: Asymmetry in fish genitalia
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Four-eyed fishes of the genus Anableps and their relatives are a fish family from the Neotropics with a number of bizarre traits that have fascinated naturalists for centuries. These include: (i) a "split" eye that allows them to see both above and under the water surface at the same time; (ii) being live-bearers, meaning that they give birth to fully developed offspring just like mammals; and (iii) conspicuously asymmetric genitalia among the males of all species and among the females of some species.
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The genitalia of the males, so-called gonopodia, are transformed anal fins that can be used as a copulatory organ to inseminate compatible females. Curiously, these penis-like structures are asymmetric and their tip is bent either to the left or to the right. Females in turn have an asymmetric overgrowth of tissue that covers the genital opening laterally. Consequently, only compatible males and females can successfully mate. Within populations, both righties and lefties exist. Strikingly, the question as to whether this asymmetry is heritable or random has remained unresolved for more than a century.New research carried out by evolutionary biologists from the University of Konstanz in collaboration with the Fundación Miguel Lillo in Argentina and published in the "We started out with a fairly simple question," says Dr Julián Torres-Dowdall, lead author on the study and a researcher in the University of Konstanz?s Zoology and Evolutionary Biology laboratory led by Professor Axel Meyer: "Do left-sided males father mostly left-sided sons? This may appear to be a strange question to ask, but for evolutionary biologists, asymmetry in general, and the issue of heritability in particular, is incredibly interesting due to its potential to drive the emergence of new species."Anablepid fishes are especially interesting not only because their genitals are asymmetric -- an uncommon trait they share with some insects, snakes, most ruminant mammals, waterfowl and certain fish families. Interestingly, individuals with left or right-sided genitalia can be found at similar proportions within populations. "This is rare and useful at the same time as it allows us to address the issue of heritability and, consequently, to understand the evolution and maintenance of both genital forms (lefties and righties) and its potential to differentiate populations and possibly speciation," adds Torres-Dowdall.To determine whether sidedness of genitalia in anablepid fishes is determined genetically and passed down to the next generation, the researchers studied two genera of the Anablepidae family: Anableps, which comprises three species of four-eyed fish, and Jenynsia, a genus comprised of 15 species of one-sided live-bearers. Combining breeding experiments with genomic analyses, the team established that there is no strong heritability to the direction of genital asymmetry in anablepid fishes."Our experiments with both captive and natural populations showed that all offspring were asymmetric -- with a near-equal proportion of left and right genitalia in the natural populations and in the breeding experiment," says Torres-Dowdall. In both cases, the sons' genital sidedness was independent from the father's sidedness. "This strongly suggests that the direction of asymmetry is determined by chance rather than heredity and goes some way towards explaining the persistence of this peculiar trait over time."The genomic analyses showed no evidence that genetic markers, i.e. specific regions of the genome, are associated with genital asymmetry. Furthermore, there was no evidence of accumulated genomic differences between left- and right-sided individuals. This conforms with the general pattern found in other species with similar asymmetric traits. Also, there is no suggestion that the existence of left and right-sided genitalia should be regarded as potential drivers of speciation: "There is the idea that incompatibility between left and right-sided individuals might potentially result in the evolution of two new asymmetric, yet either left or right-sided, species," explains Torres-Dowdall. "However, for a new species to evolve, variation in the direction of asymmetry would have to have a genetic component. Our study strongly suggests that this is not the case with anablepid fishes."
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New Species
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July 7, 2020
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https://www.sciencedaily.com/releases/2020/07/200707183918.htm
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Algae species discovered infesting NW Hawaiian waters has been identified
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A newly-identified, fast-growing species of algae poses a major threat to coral reefs and the ocean ecosystem. It was previously discovered in Papah?naumoku?kea Marine National Monument by a team of researchers from the University of Hawai?i, Western Australian Herbarium, College of Charleston and National Oceanic and Atmospheric Administration (NOAA).
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Newly-named "I think this is a warning of the kinds of changes that are to come for the northwestern Hawaiian Islands," said UH Manoa College of Natural Sciences Interim Associate Dean and Professor Alison Sherwood, the lead researcher on the project. "We have, not until now, seen a major issue like this where we have a nuisance species that's come in and made such profound changes over a short period of time to the reefs."It was not widespread when first detected by NOAA divers in 2016 but a 2019 visit to the same area revealed that it is now covering up to several thousand square meters at the Pearl and Hermes Atoll."Until we understand whether it is native or introduced, and until we better understand what is driving this outbreak, it is critically important that research divers and research ships do not inadvertently transport this species to other islands," said Randall Kosaki, NOAA research coordinator at Papah?naumoku?kea Marine National Monument. "Thus, all of our dive gear was soaked in bleach, and all of our dive boats were sprayed down with bleach prior to returning to Honolulu."The findings were featured in a Although "The main Hawaiian Islands are impacted by several well-known invasive seaweeds, but reports of nuisance algae in Papah?naumoku?kea Marine National Monument are far fewer, and none have been present at the level of abundance seen in this new alga," Sherwood said.Researchers will conduct mapping and molecular analyses, and will develop mitigation strategies to assist in the development of appropriate management actions."This is a highly destructive seaweed with the potential to overgrow entire reefs," College of Charleston Assistant Professor Heather Spalding said. "We need to figure out where it's currently found, and what we can do to manage it. This type of research needs trained divers in the water as quickly as possible. The sooner we can get back to Papah?naumoku?kea Marine National Monument, the better."
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July 2, 2020
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https://www.sciencedaily.com/releases/2020/07/200702113656.htm
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New candidate for raw material synthesis through gene transfer
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Cyanobacteria hardly need any nutrients and use the energy of sunlight. Bathers are familiar with these microorganisms -- often incorrectly called "blue-green algae" -- as they often occur in waters. A group of researchers at the Karlsruhe Institute of Technology (KIT) has discovered that the multicellular species Phormidium lacuna can be genetically modified by natural transformation and could thus produce substances such as ethanol or hydrogen.
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During transformation, a cell is genetically modified by adding genetic material (DNA). This process, which occurs frequently in nature, can be used to introduce specific DNA into a cell and endow it with a certain property. "Natural transformation means that DNA is taken up by cells without any further aids," says Professor Tilman Lamparter, professor at the Botanical Institute -- General Botany research field at the KIT. The procedure is simple: It works without conjugation -- the connection with another cell -- and without electroperforation -- which would make the cell wall permeable. Since natural transformation has so far only been successful in unicellular cyanobacteria, it was assumed that it was an exclusive feature of unicellular species. The findings of the KIT research group show that the natural competence to take up extracellular DNA occurs more frequently in cyanobacteria than previously thought. In the online scientific publication For natural transformation, the cells must be in a physiological state, known as natural competence, so that the recipient cell can actively transport DNA into the cytoplasm. The scientists took advantage of the natural transformation and integrated new genetic information into the genome of Phormidium lacuna. The multicellular cyanobacteria, which obtain their energy from sunlight, offer the advantage of forming a biofilm and of growing in a high cell density that can be quickly removed. KIT scientists isolated several strains of this filamentously growing species from the North Sea and the Mediterranean Sea and sequenced the genome of one strain.The technique established by the researchers to modify multicellular cyanobacteria by introducing genetic information opens up a wide range of possibilities for basic research and possible applications. "With the help of natural transformation, we have already created numerous so-called knockout mutants, i.e. we succeeded in switching off certain genes and thus identified their function," says Lamparter. A possible future-oriented application would be to synthesize ethanol, hydrogen or lactate as well as other bioproducts in the cells and thus contribute to the bio-economy and to the change from an oil-based economy to a market economy based on sustainable resources. "Our vision is to use this technology to replace fossil resources," says the biologist.
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June 24, 2020
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https://www.sciencedaily.com/releases/2020/06/200624100043.htm
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Four new species of giant single-celled organisms discovered on Pacific seafloor
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Two new genera and four new species of giant, single-celled xenophyophores (protozoans belonging to a group called the foraminifera) were discovered in the deep Pacific Ocean during a joint project between scientists at the National Oceanography Centre, UK (NOC), the University of Hawai'i, and the University of Geneva. 'Moana' has inspired the name Moanammina for one of the new genera, while the second has been named
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The species were described, based on morphology and genetic data, from specimens collected with the University of Hawai'i's Remotely Operated Vehicle Lu'ukai on an expedition to the western Clarion Clipperton Zone (CCZ) aboard the RV Kilo Moana in 2018. The seabed in this area is over three miles deep. The CCZ occupies a vast swathe of the Pacific Ocean with extensive seafloor polymetallic nodule deposits, and is targeted for deep-sea mining."We were excited to find these beautiful new xenophyophores," said Andrew Gooday, professor at NOC and lead author of the recently published findings. "It seemed appropriate to name one after 'Moana', a Hawaiian word meaning ocean. Xenophyophores are one of the most common types of large organism found on the CCZ abyssal plains, so the name of the second genus was chosen to reflect this."Like some other types of foraminifera, xenophyophores construct shells, called tests, composed of particles that they obtain from the surrounding environment. These are often elaborate structures that can reach sizes of four inches or more."These four new species and two new genera have increased the number of described xenophyophores in the CCZ abyss to 17 (22% of the global total for this group), with many more known but still undescribed," said Gooday. "This part of the Pacific Ocean is clearly a hotspot of xenophyophore diversity.""The abundance and diversity of these giant single-celled organisms is truly amazing!" said oceanographer Craig Smith from the UH M?noa School of Ocean and Earth Science and Technology (SOEST), co-author and Chief Scientist of the RV Kilo Moana cruise on which the xenophyophores were discovered."We see them everywhere on the seafloor in many different shapes and sizes. They clearly are very important members of the rich biological communities living in the CCZ. Among other things they provide microhabitats and potential food sources for other organisms. We need to learn much more about the ecology these weird protozoans if we wish to fully understand how seafloor mining might impact these seafloor communities."
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June 22, 2020
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https://www.sciencedaily.com/releases/2020/06/200622133024.htm
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Undergraduate student discovers 18 new species of aquatic beetle in South America
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It would be striking for a seasoned entomologist with decades of fieldwork to discover such a large number of species unknown to science. But for University of Kansas student Rachel Smith, an undergraduate majoring in ecology & evolutionary biology, the find is extraordinary: Smith recently published a description of 18 new species of aquatic water beetle from the genus Chasmogenus in the peer-reviewed journal
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"The average size of these beetles, I would say, is about the size of a capital 'O' in a 12-point font," said Smith of the collection of new species. "They spend a lot of their life in forest streams and pools. They're aquatic, so they're all great swimmers -- and they can fly."The research involved Smith traveling to Suriname to perform fieldwork as well as passing countless hours in the lab of Andrew Short, associate professor of ecology & evolutionary biology and associate curator with KU's Biodiversity Institute, who co-wrote the new paper.Smith said many of the aquatic beetle species are virtually indistinguishable simply by looking at them, even under a microscope."Something unique and fascinating about this genus, particularly the ones I worked on, is that many look almost exactly the same," she said. "Even to my trained eye, it's hard to tell them apart just based on external morphology. Their uniqueness is in there but kind of hidden in this very uniform external morphology."To identify the new species, Smith compared DNA evidence from the aquatic beetles with a few external morphological differences that could be observed. But this was not enough: Much of Smith's work also hinged on dissecting these tiny specimens collected in northeastern South America to spot key differences in their internal anatomy."Because it's difficult to tell them apart from external morphology, you kind of have to go inside," she said. "I ended up doing over 100 dissections of these beetles to extract the male genitalia and look at it under a microscope. That really was the true way to tell them apart. Ultimately, it came down to male genitalia and genetic divergence that I used to delimit many of these species."The aquatic beetles described in the new paper were collected over multiple trips to Venezuela, Suriname and Guyana. Smith herself participated in one expedition to Suriname to collect specimens."In Suriname, almost every day involved a boat ride down a river or kayaking to a location," she said. "And there would have been either a short or a long hike. One day it was up an entire mountain, another day it was just a short little hike down a river trail. Well, not necessarily a trail because there aren't trails in the rainforest. We'd find an area that had some small, slow-moving or stagnant pools. The best ones are usually still and have dead leaves and mud and detritus -- that's where a lot of these beetles are found. You definitely have to get dirty to do this work, but it's very satisfying."Indeed, one of the beetles Smith and her fellow researchers discovered in the Suriname rainforest ended up being unknown to science."I was part of a group that collected one of the beetles that was named in this paper," she said. "So, I was involved in the entire process of naming a species -- going to the rainforest, collecting it, bring it back to the lab, naming it and describing it. It was so nice to be a part of the whole process of discovering a new species."Smith's co-author and faculty mentor Short said her paper reflects two years of work and is a remarkable accomplishment for any scientist, much less an undergraduate student."While new species for me are common, this is quite a lot for one paper and a huge amount for a student to describe," he said. "Rachel has done a great job. An undergraduate describing 18 species is extraordinary -- it's rare even for experienced scientists. I've described a lot of new species but never as many as 18 at once. This work highlights just how little we know about how many species there are in South America."Smith said after graduation from KU in December, her aim is to develop a career in fieldwork and research, to uncover hidden biodiversity in hopes that it can empower conservation efforts in threatened areas."I've always had my sights set on a larger picture, and conservation really is my ultimate goal," she said. "You have to start from the bottom up, with taxonomy. You can't really know the efficacy of any kind of conservation effort without knowing what you're protecting or any idea of how many species are there. As I described in this paper, over half of these species are microendemic, meaning that they only occur in one specific locality. So, it begs the question -- is there something unique in that area that these beetles are specializing on, and what kind of kind of niches or roles do they play in that ecosystem? Hopefully it leads to a larger conversation about taking action to get certain areas protected."Smith said destruction of such habitats could lead to an incalculable loss of biodiversity, but taxonomists could inform debates that pit species conservation against economic gains that come from extraction of natural resources."There's deforestation and logging and a lot of gold mining in this particular area where I was at in Suriname," she said. "But I think the take-home message from this paper really is that biodiversity is found in even in the smallest puddles in South America."
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June 18, 2020
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https://www.sciencedaily.com/releases/2020/06/200618150302.htm
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Genetic variation may affect bacterial composition and healing of wounds
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Genetic variability across patients might play an important role in shaping the microbiome composition of wounds, thereby influencing the healing process, according to a study published June 18 in the open-access journal
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Chronic wounds, which fail to show signs of healing within three weeks, are a costly burden to patients. Bacterial infection of wounds plays an important role in stalling the healing process. A variety of bacterial species are present in chronic wounds, but it is unknown why certain species are observed in some wound infections and not others. To address this question, Phillips and colleagues conducted a genome-wide association study to identify genomic loci associated with microbiome diversity in chronic wounds. According to the authors, this study is the first to identify genetic determinants of wound microbiomes and healing in patients.Specifically, the researchers found that genetic variation in the TLN2 and ZNF521 genes was associated with both the number of bacteria observed in wounds and the abundance of common pathogens (primarily Pseudomonas aeruginosa and Staphylococcus epidermidis). Moreover, Pseudomonas-infected wounds had fewer species, and wounds with fewer species were slower to heal. The researchers also used biomarkers to predict the number of species observed during infection. Overall, the results suggest that genetic variation influences the types of bacteria that infect wounds as well as the healing process. According to the authors, biomarkers for chronic wound microbiomes could be used to guide treatment by providing information about which patients are at risk of developing certain types of persistent infections. Given that wound persistence is associated with the development of multiple drug-resistant pathogens, such biomarkers could be used to identify which patients should receive early and aggressive targeted therapy.The authors add, "This study demonstrates the ability to find variants in people's genomes that explain differences in the microorganisms that infect their wounds. Such information is expected to guide new understanding about the mechanisms of infection and healing, and the establishment of predictive biomarkers that improve patient care."
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New Species
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June 16, 2020
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https://www.sciencedaily.com/releases/2020/06/200616083402.htm
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Australian fossil reveals new plant species
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Antoine Champreux, a PhD student in the Global Ecology Lab at Flinders University, has catalogued the discovery of the new fern-like plant species as part of an international effort to examine the Australian fossil in greater detail.
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The fossil was found in the 1960s by amateur geologist Mr John Irving, on the bank of the Manilla River in Barraba, New South Wales. The fossil was exposed after major flooding events in 1964, and Mr Irving gave the fossil to the geological survey of New South Wales, where it remained for more than 50 years without being studied.It was dated from the end of the Late Devonian period, approximately 372-to-359 million years ago -- a time when Australia was part of the Southern hemisphere super-continent Gondwana. Plants and animals had just started to colonise continents, and the first trees appeared. Yet while diverse fish species were in the oceans, continents had no flowering plants, no mammals, no dinosaurs, and the first plants had just acquired proper leaves and the earliest types of seeds.Well-preserved fossils from this era are rare -- elevating the significance of the Barraba plant fossil.The fossil is currently in France, where Brigitte Meyer-Berthaud, an international expert studying the first plants on Earth, leads a team at the French laboratory of Botany and Modelling of Plant Architecture and Vegetation (AMAP) in Montpellier. This French laboratory is particularly interested in further examination of Australian fossils from the Devonian-Carboniferous geological period, to build a more detailed understanding of plant evolution during this era.Mr Champreux studied the fern-like fossil during his master's degree internship at AMAP and completed writing his research paper during his current PhD studies at Flinders University."It's nothing much to look at -- just a fossilised stick -- but it's far more interesting once we cut it and had a look inside," says Mr Champreux. "The anatomy is preserved, meaning that we can still observe the walls of million-year-old cells. We compared the plant with other plants from the same period based on its anatomy only, which provide a lot of information."He found that this plant represents a new species, and even a new genus of plant, sharing some similarities with modern ferns and horsetails."It is an extraordinary discovery, since such exquisitely-preserved fossils from this period are extremely rare," he says. "We named the genus Keraphyton (like the horn plant in Greek), and the species Keraphyton mawsoniae, in honour of our partner Professor Ruth Mawson, a distinguished Australian palaeontologist who died in 2019."An article describing the new plant -- Keraphyton gen. nov., a new Late Devonian fern-like plant from Australia, by A Champreux, B Meyer-Berthaud and A-L Decombeix -- has been published in the scientific journal
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June 12, 2020
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https://www.sciencedaily.com/releases/2020/06/200612111437.htm
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Water bacteria have a green thumb
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The sheer endless expanses of the oceans are hostile deserts -- at least from the perspective of a bacterium living in water. Tiny as it is, its chances of finding sufficient nutrients in the great mass of water would seem to be vanishingly small. However, as in other deserts, there are life-saving oases in the sea: for example, microorganisms find everything they need to live on the surfaces of aquatic plants and algae. Here, very different species can grow within the community of a biofilm, as it is called, where they exchange information and offer each other protection.
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Jena microbiologists working with Prof. Christian Jogler have now discovered natural products in a newly discovered species of bacteria, with the help of which the microorganisms living in the water control the composition of such biofilms and cultivate them like a garden, in line with their own needs. The team from Germany and the Netherlands presents its results in the current issue of the journal The bacterium Stieleria maiorica is one of nearly 80 newly discovered species of bacteria, which the team from the University of Jena has been cultivating from fresh and saltwater samples from all over Europe and the USA, obtained in a large-scale collection. Stieleria maiorica is a member of the planctomycetes and was fished out of the Mediterranean Sea off the coast of Majorca. The researchers are particularly interested in such planctomycetes because they suspect that they contain bioactive natural products. And rightly so, as the Jena scientists have shown in their latest paper. Stieleria maiorica, for instance, produces a previously unknown group of chemical compounds, which were named "stieleriacine," after the bacterium."These are relatively small molecules, which are structurally similar to a group of known signal molecules that microorganisms use to communicate with each other," says Christian Jogler. "This led to the assumption that the newly discovered stieleriacines also act as signalling molecules in the broadest sense," adds Jogler, who is Professor for Microbial Interactions at the University of Jena.The researchers have therefore been examining how other bacterial species react to the stieleriacines produced by planctomycetes. And they indeed discovered that species of Roseobacter react to the stieleriacine signal. Like planctomycetes, these microorganisms occur on aquatic plants and algae and compete with the planctomycetes for habitat and nutrients. The stieleriacines promote the growth of some Roseobacter species, while inhibiting others. What is more, those species that grow better as a result of the chemical signal also produce an antibiotic which they release into their environment. Roseobacter that are inhibited in their growth by the stieleriacines do not produce an antibiotic."This is a crucial advantage for the planctomycetes," says Prof. Jogler. "They themselves are resistant to the antibiotic. Other species of bacteria, however, which compete with the planctomycetes in the biofilm, are inhibited by the antibiotic." This gives the rather slow-growing planctomycetes the chance to compete with bacterial species which would otherwise have made things difficult for them. "One could say that planctomycetes use the Roseobacter for the 'heavy manual work' of adapting the composition of the biofilm to their own requirements and, like skilled gardeners, for regulating the growth of other species."However, for Prof. Jogler and his colleagues in the Cluster of Excellence "Balance of the Microverse" at Jena University, the planctomycetes are of interest not only as skilful underwater landscape gardeners. "The chemical signalling substances that the microorganisms use to communicate and to influence their environment could also be of use in infection research," says Jogler. If small molecules can be used to modulate the composition of biofilms, this could be used, for example, to prevent pathogenic microorganisms from settling on the surfaces of catheters or implants.With the present study, the authors feel confirmed in their hypothesis that in the search for new active substances, and in particular for the new antibiotics that are so crucial, it is worth taking a look below the surface of the water. They are convinced that other natural substances with bioactive properties could still be found in the biofilms on aquatic plants and algae.
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June 11, 2020
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https://www.sciencedaily.com/releases/2020/06/200611114532.htm
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A new character for Pokémon? Novel endemic dogfish shark species discovered from Japan
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Newly discovered creatures can often be as impressive and exciting as the ones from the Japanese movies and shows. Many of those fictional characters, including inhabitants of the famous Pokémon universe, might have their analogues among the real animals native to Japan. Maybe, a new species of the dogfish shark published in the open-access journal
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A new deep-water dogfish shark: The new shark has the body length of 59-77 cm and some unique characteristics such as tall first dorsal fin and caudal fin with broad white margins. Currently, the species is known exclusively as a Japanese endemic, occurring in the tropical shallow waters of Southern Japan in the North-western Pacific.Spurdogs represent commercially important for the world fish trade taxa. They are caught for a range of purposes: consumption of meat, fins and liver oil. Despite their high occurrence, the accurate identification data of species is scarce, population threats and trends remain unknown.Japan currently represents one of the world's leading shark fish trade countries, though, during the last decades the amount of shark catches is decreasing and over 78 elasmobranch species traded in Japanese shark fin markets are now evaluated as threatened.The new species Squalus shiraii previously used to be massively misidentified with shortspine spurdog, due to the resembling shape of body, fins and snout length. However, there are some differences, defining the specificity of the new species."Squalus shiraii has body brown in colour, postventral and preventral caudal margins whitish, dorsal and ventral caudal tips broadly white and black upper caudal blotch evident in adults. S. mitsukurii has body conspicuously black to dark grey and caudal fins black throughout with post-ventral caudal margin fairly whitish and black upper caudal blotch not evident in adults," shares lead author Dr. Viana.Scientists propose the name for the newly described species as Shirai's spurdog in honor to Dr. Shigeru Shirai, the former Japanese expert of the group.
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May 27, 2020
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https://www.sciencedaily.com/releases/2020/05/200527105023.htm
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Finding a genus home for Alaska's dinosaurs
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A re-analysis of dinosaur skulls from northern Alaska suggests they belong to a genus that lived over a broad latitudinal range extending into the Arctic.
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The plant-eating, broad-beaked dinosaurs that lived in northern Alaska some 69 million years ago belong to the genus Edmontosaurus, and not to the genus recently proposed by scientists in 2015. The finding suggests this group of dinosaurs existed over a broad latitudinal range, extending from northern Colorado all the way up into the Arctic.The research was conducted as part of a Perot Museum of Nature and Science's project, joined by Hokkaido University and Okayama University, and published in the journal The Liscomb Bonebed quarry in northern Alaska is rich in dinosaur fossils belonging to the family Hadrosauridae. Biological classifications, or taxonomy, of the hadrosaurid dinosaur found there has puzzled scientists since the 1980s. Scientific consensus eventually classified them as the genus Edmontosaurus, until a group of scientists proposed that the Alaskan hadrosaurids represent a unique genus and species, and named Ugrunaaluk in 2015. However, other scientists questioned the validity of the taxon.The incompleteness and the immaturity of the Alaskan hadrosaurine fossils make their classification difficult. To overcome this problem, Ryuji Takasaki, former Ph.D. student at Hokkaido University, and his colleagues in Japan and the US specifically examined skull bones. This minimized danger of mixing bones of the two hadrosaurid clades known from the same site: Hadrosaurinae and Lambeosaurinae. Bones from body parts of immature hadrosaurine and lambeosaurine dinosaurs cannot be readily distinguished from each other.The team compared the skull bones of Hadrosaurinae with those of other hadrosaurines, especially with known Edmontosaurus from lower latitude North America. They found enough evidence to suggest that the Liscomb Bonebed hadrosaurine bones previously named Ugrunaaluk are likely to represent an immature form of the genus Edmontosaurus."We recommend the conservative approach of referring them to Edmontosaurus until further discoveries of more mature individuals from the area can resolve the issue," says Takasaki.Clarifying the taxonomy of the Liscomb Bonebed hadrosaurines can help scientists understand how they lived and evolved. "Re-attribution of the Alaskan hadrosaurines to Edmontosaurus suggests they lived over a broad range of latitudes extending from northern Colorado to northernmost Alaska," says Takasaki. The few anatomical differences among Edmontosaurus, despite of their broad range, suggest they did not evolve much in order to adapt. A small temperature gradient over that area at that time could be one reason to establish the small differences, according to the researchers.Moreover, Yoshitusugu Kobayashi at Hokkaido University Museum, a co-author of this paper, recently named a new genus species Kamuysaurus japonicus in Hokkaido, Japan, which belongs to Edmontosaurini as Edmontosaurus does. "Taken these studies together, this group of hadrosaurs, the Edmontosaurini, were widely distributed in the northern circum-Pacific region, meaning that they were incredibly successful dinosaurs," Kobayashi commented. "It's fascinating to think they likely used the ancestral Bering Land Bridge between Asia and North America for migration in a manner similar to mammoths, woolly rhinoceroses, and early humans."
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May 26, 2020
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https://www.sciencedaily.com/releases/2020/05/200526145310.htm
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Can e-learning help stem the threat of invasive alien species such as Japanese Knotweed?
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E-learning could be a crucial tool in the biosecurity fight against invasive alien species such as Japanese Knotweed, Zebra Mussels and Signal Crayfish according to a new study published in the academic journal
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According to previous studies, the cost of invasive alien species is estimated to be £1.7billion per annum. Governments across the UK have launched regular public awareness campaigns aimed such as 'Check Clean Dry' which was aimed at increasing awareness of biosecurity measures among people such as anglers and recreational boaters.In the study, led by Cranfield University's Dr Caitriona Shannon, over 600 field workers and researcher were surveyed before, and six months after undertaking an e-learning course on invasive alien species and biosecurity practices. The study was carried out at the University of Leeds and funded by the Natural Environment Research Council (NERC).After following the 'Better Biosecurity' e-Learning course, the participants showed not only a much greater knowledge of the risk of accidentally spreading invasive species through their work, but they also demonstrated an increase in biosecurity behaviour and cleaning practices.The paper is the first to evaluate the effectiveness of e-learning as a tool to increase awareness, risk perception and biosecurity behaviour in relation to invasive alien species among individuals conducting work activities or research (fieldwork) in the field.Dr Caitriona Shannon, Research Fellow in Perceptions & Behaviour at Cranfield University, said: "Invasive alien species do tremendous damage to the UK's natural environment and costs the economy billions of pounds a year. Often the spread of these species is accidental and caused by a low level of biosecurity knowledge and poor cleaning practices. This study shows the effectiveness of the role e-learning can play in improving the nation's biosecurity levels and safeguarding our indigenous species."As we all adapt to new ways of working, such as delivering teaching online, this study also illustrates just how effective e-learning can be as an educational tool."
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May 15, 2020
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https://www.sciencedaily.com/releases/2020/05/200515115650.htm
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Bizarre new species discovered... on Twitter
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While many of us use social media to be tickled silly by cat videos or wowed by delectable cakes, others use them to discover new species. Included in the latter group are researchers from the University of Copenhagen's Natural History Museum of Denmark. Indeed, they just found a new type of parasitic fungus via Twitter.
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It all began as biologist and associate professor Ana Sofia Reboleira of the National Natural History Museum was scrolling though Twitter. There, she stumbled upon a photo of a North American millipede shared by her US colleague Derek Hennen of Virginia Tech. She spotted a few tiny dots that struck her well-trained eyes."I could see something looking like fungi on the surface of the millipede. Until then, these fungi had never been found on American millipedes. So, I went to my colleague and showed him the image. That's when we ran down to the museum's collections and began digging," explains Ana Sofia Reboleira.Together with colleague Henrik Enghoff, she discovered several specimens of the same fungus on a few of the American millipedes in the Natural History Museum's enormous collection -- fungi that had never before been documented. This confirmed the existence of a previously unknown species of Laboulbeniales -- an order of tiny, bizarre and largely unknown fungal parasites that attack insects and millipedes.The newly discovered parasitic fungus has now been given its official Latin name, Ana Sofia Reboleira points out that the discovery is an example of how sharing information on social media can result in completely unexpected results:"As far as we know, this is the first time that a new species has been discovered on Twitter. It highlights the importance of these platforms for sharing research -- and thereby being able to achieve new results. I hope that it will motivate professional and amateur researchers to share more data via social media. This is something that has been increasingly obvious during the coronavirus crisis, a time when so many are prevented from getting into the field or laboratories."Reboleira believes that social media is generally playing a larger and larger role in research.She stresses that the result was possible because of her access to one of the world's largest biological collections."Because of our vast museum collection, it was relatively easy to confirm that we were indeed looking at an entirely new species for science. This demonstrates how valuable museum collections are. There is much more hiding in these collections than we know," says Ana Sofia Reboleira.Laboulbeniales-fungi look like tiny larvae. The fungi are in a class of their own because they live on the outside of host organisms, and even on specific parts of bodies -- in this case, on the reproductive organs of millipedes. The fungus sucks nutrition from its host animal by piercing the host's outer shell using a special suction structure, while the other half of the fungus protrudes.Approximately 30 different species of parasitic Laboulbeniales-fungi attack millipedes. The vast majority of these were only discovered after 2014. According to Reboleira, there are most likely a great number remaining to be discovered. Research in the area of Laboulbeniales remains extremely scarce.Nor is much known about their own biology, says Reboleira, who researches these fungi on a daily basis. She believes that these fungi can not only teach us about the insects upon which they live, but also about the mechanisms behind parasitism itself -- that is, the relationship between parasites and their hosts. She hopes that the research will also provide useful knowledge about the parasites that attack and can be harmful to human health.
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New Species
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April 29, 2020
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https://www.sciencedaily.com/releases/2020/04/200429144920.htm
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Algae in the oceans often steal genes from bacteria
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Algae in the oceans often steal genes from bacteria to gain beneficial attributes, such as the ability to tolerate stressful environments or break down carbohydrates for food, according to a Rutgers co-authored study.
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The study of 23 species of brown and golden-brown algae, published in the journal "The vast group of species called CRASH, including algae such as diatoms and dinoflagellates, as well as members of the group (alveolates) that includes the malaria parasite and another group (oomycetes) that includes the potato blight pathogen, creates and consumes immense amounts of organic matter," said corresponding author Debashish Bhattacharya, a distinguished professor in the Department of Biochemistry and Microbiology in the School of Environmental and Biological Sciences at Rutgers University-New Brunswick. "There are hundreds of thousands of CRASH species and they have thrived on Earth for more than a billion years."The scientists, led by researchers at the Chinese Academy of Fishery Sciences, created a massive genomic dataset of more than 524,000 protein sequences from 23 CRASH species and used sophisticated methods to analyze the data.The results showed that gene stealing or acquisition (known as horizontal gene transfer) varies substantially among different CRASH species, with 0.16 percent to 1.44 percent of their genes (an average of 1 percent) coming from bacteria.
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New Species
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April 27, 2020
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https://www.sciencedaily.com/releases/2020/04/200427125158.htm
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New species of moths discovered in the Alps named after three famous alpinists
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The discovery of new, still unnamed animal species in a well-researched European region like the Alps is always a small sensation. All the more surprising is the description of a total of three new to science species previously misidentified as long-known alpine moths.
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During a genetic project of the Tyrolean State Museums in Innsbruck (Austria), Austrian entomologist and head of the Natural Science Collections Peter Huemer used an integrative research approach that relies on molecular methods to study four European moths. Despite having been known for decades, those species remained quite controversial, because of many unknowns around their biology.At the end, however, it turned out that the scientist was not dealing with four, but seven species. The three that were not adding up were indeed previously unknown species. Therefore, Huemer described the moths in a paper in the open-access, peer-reviewed journal "The idea to name the new species in honour of three world-renowned climbers was absolutely no coincidence," explains Huemer.One of the newly described species, "So what could have been a better fit for a name for the species that flutters on the doorstep of his residence, the Juval Castle in South Tyrol?" says Huemer.The second new species, The third alpinist, whose name is immortalised in a species name, is David Lama, specially recognised by Huemer for his commitment to conservation. Once, in order to protect endangered butterflies along the steep railway embankments in Innsbruck, Lama took care to secure volunteers in a remarkable action. Nevertheless, Lama earned his fame for his spectacular climbing achievements. His was the first free ascent of the Compressor route on the south-eastern flank of Cerro Torre."Unfortunately, David lost his life far too soon in a tragic avalanche accident on 16 April 2019 in Banff National Park, Canada. Now, The newly described moth species are closely related and belong to the genus Caryocolum of the so-called Curved-horn moths (family Gelechiidae).As caterpillars, the species of this genus live exclusively on carnation plants. Even though the biology of the new moths is still unknown, because of their collection localities, it could be deduced that plants such as the stone carnation are likely their hosts. All species are restricted to dry and sunny habitats and sometimes inhabit altitudes of up to 2,500 m. So far, they have only been observed with artificial light at night.While Messner's Curved-horn moth occurs from northern Italy to Greece, the area of ??Habeler´s Curved-horn Moth is limited to the regions between southern France, northern Switzerland and southeastern Germany. On the other hand, Research on alpine butterflies and moths has been an important scientific focus at the Tyrolean state museums for decades. In 30 years, Peter Huemer discovered and named over 100 previously unknown to science species of lepidopterans. All these new discoveries have repeatedly shown the gaps in the study of biodiversity, even in Central Europe."How could we possibly protect a species that we don't even have a name for is one of the key questions for science that derives from these studies," says Huemer in conclusion.
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New Species
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April 24, 2020
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https://www.sciencedaily.com/releases/2020/04/200424150740.htm
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Climate change may push some species to higher elevations -- and out of harm's way
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A new WCS-led study reveals that mountain-dwelling species fleeing warming temperatures by retreating to higher elevations may find refuge from reduced human pressure.
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A new study published in Without factoring in human pressure, the authors warn that conservation actions may be misguided. Factoring in human pressure reveals the true 'shape' of a mountain for species that are restricted to intact landscapes, which are often the species of greatest conservation concern. Here, the 'true shape' refers to how much land area is potentially available as habitat for a species as it moves up in elevation, not simply how much total land area is available. The true shape can reveal where species will tend to lose versus gain intact land area as they shift under climate change: the elevations where species are expected to lose area represent the priority zones for conservation.Mountains are home to over 85 percent of the world's amphibians, birds, and mammals, making them global conservation priorities. But mountain-dwelling species are at risk from human activities, such as agriculture, livestock grazing, and development that reduce their habitat, and climate change that threatens to push species upslope as they struggle to find tolerable temperatures."Species are adapted to certain temperature conditions. As temperatures warm in mountains, scientists have documented species moving to higher elevations to maintain the same temperatures," said Paul Elsen, a WCS Climate Adaptation Scientist and lead author of the study. "This was always seen as a problem, because species would have less land area and less habitat to occupy at high elevations. But what we found is that as species move upslope, they tend to move away from areas that are already under intense human pressure and into areas with reduced human pressure. As a result, they can occupy more intact land area, even if the total amount of land area declines."The authors combined several global databases to make their assessments: high-resolution digital elevation models gave a picture about how much surface area is available at different elevations. The Human Footprint Index provided information on pressure from human activities. Global climate models projected how temperatures are likely to change by the late 21st century.The authors then used computer simulations to place hundreds of thousands of hypothetical 'species' across all mountain ranges at different elevations and then predicted how they would shift their ranges based on climate projections. For each simulation, they compared the amount of area the species had to begin with to the amount they would have after the range shift under climate change.Said Elsen: "We were surprised to find that many species had more intact land area available after the range shift compared to when they started."The results suggest that many species in mountain ranges may have more intact land area available in the future if they track warming temperatures to higher slopes, though there were exceptions."Our results offer a glimmer of hope for montane species under climate change," Elsen said. "Montane species are still facing tremendous human pressure, especially at low elevations, but we have the opportunity now to protect intact habitats at higher elevations to give these species the best possible chance going forward."
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New Species
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April 21, 2020
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https://www.sciencedaily.com/releases/2020/04/200421094259.htm
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Welcome to the House of Slytherin: Salazar's pit viper, a new green pit viper from India
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A new green pit viper species of the genus Trimeresurus was discovered during the herpetological expedition to Arunachal Pradesh in India, part of the Himalayan biodiversity hotspot. The scientists named the newly-discovered snake Trimeresurus salazar after a Parselmouth (able to talk with serpents) wizard, co-founder of Hogwarts School of Witchcraft and Wizardry and the founder of the House of Slytherin -- Salazar Slytherin, the fictional character of J.K. Rowling's saga "Harry Potter." The discovery, authored by Zeeshan Mirza of the National Centre for Biological Sciences, Bengaluru, Mr. Harshal and Mr. Mandar of the Bombay Natural History Society, Mumbai, Mr. Gowande of Pune's Fergusson College and Mr. Phansalkar of the Wildlife Institute of India, Dehradun, is published in the open-access journal
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The pit vipers in the genus Trimeresurus are charismatic venomous serpents, distributed widely across east and southeast Asia. In total, the genus includes at least 48 species, with fifteen representatives occurring in India. The species belonging to the genus are morphologically cryptic, which makes it difficult to distinguish them in the field. As a result, their real diversity could be underestimated.Arunachal Pradesh, where the new species was found, belongs to the Himalayan biodiversity hotspot, which explains the diverse flora and fauna being continuously discovered there.The new green pit viper demonstrates a unique orange to reddish stripe, present on the head and body in males.Explaining the name of the new species, the scientists suggest that it is colloquially referred to as the Salazar's pit viper.This is already the second species discovered within the course of the expedition to Arunachal Pradesh, which reflects the poor nature of biodiversity documentation across north-eastern India."Future dedicated surveys conducted across northeastern India will help document biodiversity, which is under threat from numerous development activities that include road widening, agriculture, and hydro-electric projects," shares the lead researcher Dr. Zeeshan A. Mirza from National Centre for Biological Science of Bangalore, India.
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New Species
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April 21, 2020
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https://www.sciencedaily.com/releases/2020/04/200421090552.htm
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New ethane-munching microbes discovered at hot vents
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Researchers from the Max Planck Institute for Marine Microbiology and the MARUM -- Center for Marine Environmental Sciences, Bremen have discovered a microbe that feeds on ethane at deep-sea hot vents. They also succeeded in cultivating this microbe in the laboratory. What is particularly remarkable is that the mechanism by which it breaks down ethane is reversible. In the future, this could allow to use these microbes to produce ethane as an energy source. The study has now been published in the journal
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Unlike animals, which only digest proteins, carbohydrates and fats, microorganisms also feed on a variety of other organic compounds. Even natural gas does not stop them. Researchers from Bremen have now discovered a microbe in the deep sea that eats ethane, which, with a share of up to 15%, is the second most common component of natural gas.The research group led by Gunter Wegener from the Max Planck Institute for Marine Microbiology, in cooperation with researchers from other institutes, discovered the previously unknown microbe in the seafloor of the Guaymas Basin at a water depth of 2000 meters in the Gulf of California. "The Guaymas Basin is a natural laboratory teeming with new species," Wegener said. "Responsible for this extraordinary diversity are hot fluids gushing out of the seafloor, which attract many different species. Already today, we have discovered many organisms in this habitat."Some natural gas components such as propane or butane can be broken down by bacteria alone. However, in order to degrade the main components of natural gas -- methane and ethane -- two different organisms are necessary according to the present state of research, which form a so-called consortium: Archaea, which break down the natural gas, and bacteria, which couple the electrons released in the process to sulfate, an abundant compound in the ocean. Studying the biochemical processes in the consortia in the laboratory has been extremely challenging up to now: These organisms grow very slowly and only divide every few months. Thus, there was always little biomass available.This is different with the ethane producers that have now been discovered: "These consortia are growing much faster," reported Cedric Hahn, PhD student at the Max Planck Institute for Marine Microbiology and first author of the study. The cells double every week. "The laboratory cultures keep me pretty busy. But this way we now have enough biomass for extensive analyses. For example, we were able to identify key intercellular intermediates in ethane degradation. Also, we present the first complete genome of a natural gas-degrading archaea in this study."The newly discovered archaea was named The researchers also discovered something else: The ethane degradation of this microbe is reversible. Thus, relatives of This way, the microbes described here are significant for the global carbon cycle and the rising atmospheric carbon dioxide concentration in two ways: On the one hand, they use ethane in the deep sea and thus prevent this gas from reaching the atmosphere. On the other hand, they could offer a solution for the industry to reduce its carbon emissions. "This is still a long way off," Wegener said. "But we are pursuing our research. One thing we know for sure: We shouldn't underestimate the smallest inhabitants of the sea!"
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New Species
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April 7, 2020
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https://www.sciencedaily.com/releases/2020/04/200407215655.htm
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Coquí fossil from Puerto Rico takes title of oldest Caribbean frog
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The bright chirp of the coquí frog, the national symbol of Puerto Rico, has likely resounded through Caribbean forests for at least 29 million years.
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A new study published in "It's a national treasure," said David Blackburn, Florida Museum curator of herpetology and the study's lead author. "Not only is this the oldest evidence for a frog in the Caribbean, it also happens to be one of the frogs that are the pride of Puerto Rico and related to the large family Eleutherodactylidae, which includes Florida's invasive greenhouse frogs."Jorge Velez-Juarbe, associate curator of marine mammals at the Natural History Museum of Los Angeles County, found the fossil on a river outcrop in the municipality of San Sebastian in northwestern Puerto Rico. Velez-Juarbe and his collaborators' previous collecting efforts at the site uncovered fossil seeds, sea cows, side-necked turtles and the oldest remains of gharials and rodents in the Caribbean, dating to the early Oligocene Epoch, about 29 million years ago.Still, "there have been many visits from which I have come out empty-handed over the last 14 years," he said. "I've always kept my expectations not too high for this series of outcrops."On this trip in 2012, he combed the deposits for half a day without much luck when a small bone, partially exposed in the sediment, caught his eye. He examined it with his hand lens."At the moment, I couldn't wrap my mind as to what it was," Velez-Juarbe said. "Then once I got back home, cleaned around it with a needle to see it better and checked some references, I knew I had found the oldest frog in the Caribbean."The ancient coquí displaces an amber frog fossil discovered in the Dominican Republic in 1987 for the title of oldest Caribbean frog. While the amber fossil was originally estimated to be 40 million years old, scientists now date Dominican amber to about 20 million to 15 million years ago, Blackburn said.Based on genetic data and family trees, scientists had hypothesized rain frogs lived in the Caribbean during the Oligocene, but lacked any fossil evidence. The small, lightweight bones of frogs often do not preserve well, especially when combined with the hot, humid climate of the tropics.Matching a single bone fragment to a genus or species "is not always an easy process," Velez-Juarbe said. It can also depend on finding the right expert. His quest for help identifying the fossil turned up empty until a 2017 visit to the Florida Museum where he had once been a postdoctoral researcher."I got to talk with Dave about projects, and the rest is now history," he said.Possibly first arriving in the Caribbean by rafting from South America, frogs in the genus "This is the most diverse group by two orders of magnitude in the Caribbean," Blackburn said. "They've diversified into all these different specialists with various forms and body sizes. Several invasive species also happen to be from this genus. All this raises the question of how they got to be this way."One partial arm bone may not tell the whole story of coquí evolution -- but it's a start."I am thrilled that, little by little, we are learning about the wildlife that lived in Puerto Rico 29-27 million years ago," Velez-Juarbe said. "Finds like this help us unravel the origins of the animals we see in the Caribbean today."
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New Species
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April 7, 2020
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https://www.sciencedaily.com/releases/2020/04/200407131459.htm
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How wallflowers evolved a complementary pair of plant defenses
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A pair of chemicals used by wallflowers and their kin to ward off predators have evolved to complement each other, with one targeting generalist herbivores and the other targeting specialised herbivores that have become resistant to the generalist defence.
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Plants are engaged in an ongoing arms race with the creatures that eat them. They evolve defences to deter plant eaters, while their herbivores evolve counter-defences. The new study, published today in The first line of defence in all Brassicaceae plants are chemicals called glucosinolates, which are activated when predatory creatures nibble on the plants. More recently, wallflowers have developed a second line of defence by producing chemicals called cardenolides to deter plant-eating creatures that evolved defences to glucosinolates."Studying how these two defences evolved in this large genus can help scientists understand the trade-offs that the plants face as they try to defend themselves against multiple enemies," explains lead author Tobias Züst, PhD, Research Associate at the Institute of Plant Sciences, University of Bern, Switzerland.To do this, Züst and his team sequenced the genome of the wormseed wallflower, a short-lived wild mustard. They next created a detailed family tree for this plant and 47 other wallflower species and compared the diversity and abundance of glucosinolates and cardenolides across these species. They found that the two defences varied independently of each other, and that closely related, geographically co-occurring species shared similar cardenolide traits, but not glucosinolate traits. This is likely a result of separate selective pressures acting on each defence."Even though most species co-expressed two different types of potentially costly chemical defences, there was no evidence of a trade-off between glucosinolates and cardenolides," Züst says. "Instead, these two types of chemicals appear to complement each other and do not serve redundant functions."Züst adds that the emergence of cardenolides corresponds with an explosion in the number of wallflower species, which suggests this second complementary defence may have allowed these plants to succeed and diversify into new habitats."Further analysis of the wormseed wallflower genome will be needed to help scientists identify glucosinolate and cardenolide-producing genes in this species, as well as aid our understanding of the function of these chemicals in the evolution of Brassicaceae defences," concludes senior author Georg Jander, Professor at the Boyce Thompson Institute in Ithaca, New York, US.
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New Species
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April 2, 2020
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https://www.sciencedaily.com/releases/2020/04/200402100856.htm
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Fourth new pterosaur discovery in matter of weeks
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You wait ages for a pterosaur and then four come along at once.
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Hot on the heels of a recent paper discovering three new species of pterosaur, University of Portsmouth palaeobiologists have identified another new species -- the first of its kind to be found on African soil.Pterosaurs are the less well-known cousins of dinosaurs. They had adept flying ability -- some as large as a fighter jet and others as small as a model aeroplane.The new species belongs to a group of pterosaurs called tapejarids from the Cretaceous period. Tapejarids were small to medium-sized pterosaurs with wingspans perhaps as wide as four metres, most of which had large, broad crests sweeping up from the front of the skull.They are well known in Brazil and China, and specimens have also been discovered in Europe, but this is the first time the flying reptile has been found in Africa.It differs from the three recent species discovered as this one had no teeth -- it was 'edentulous'.Professor David Martill, from the University's School of the Environment, Geography and Geosciences, led the study. He said: "The study of Moroccan material shows that we are still far from having found all the paleontological treasures of North Africa. Even fragmentary fossils, like the jaw piece of the new pterosaur, can give us important information about the biodiversity of the past."PhD student Roy Smith, one of the co-authors, said: "I feel very privileged to be part of such an exciting discovery. Working in the Sahara was a life-changing experience, and discovering a new species of pterosaur is the icing on the cake."The new pterosaur has been named Afrotapejara zouhrii to honour the Moroccan palaeontologist Professor Samir Zouhri. Originally a mammal specialist, Zouhri also contributed to several discoveries of prehistoric reptiles in Morocco, including dinosaurs and pterosaurs.Professor Martill said: "The opportunity to illuminate the diversity of pterosaurs in Africa while honouring a colleague does not happen every day."The research team included Dr David Unwin from the University of Leicester and Dr Nizar Ibrahim from the University of Detroit Mercy.Palaeontologist Dr Ibrahim, said: "Samir Zouhri has played an important role in the development of Moroccan palaeontology, not only through his publications, but also because he organised scientific conferences in Morocco and edited an entire volume for the Geological Society of France on the subject of vertebrate palaeontology in Morocco."The fossil material is part of the collections of the Faculty of Sciences Aïn Chock, Casablanca Hassan II University and the paper was published in
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New Species
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March 26, 2020
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https://www.sciencedaily.com/releases/2020/03/200326124155.htm
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As the ocean warms, marine species relocate toward the poles
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Since pre-industrial times, the world's oceans have warmed by an average of one degree Celsius (1°C). Now researchers report in
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"The main surprise is how pervasive the effects were," says senior author Martin Genner, an evolutionary ecologist at the University of Bristol. "We found the same trend across all groups of marine life we looked at, from plankton to marine invertebrates, and from fish to seabirds."The new study builds on earlier evidence for a prevailing effect of climate change on the distributions, abundance, and seasonality of marine species. Based on those findings, Genner's team reasoned that marine species should be doing well at the leading (poleward) edge of their ranges but poorly at their trailing (equatorward) side. They also realized that existing databases of global species distributions could be used to test this hypothesis.Based on a thorough search of available data in the literature, the researchers now report on a global analysis of abundance trends for 304 widely distributed marine species over the last century. The results show that -- just as predicted -- abundance increases have been most prominent where sampling has taken place at the poleward side of species ranges, while abundance declines have been most prominent where sampling has taken place at the equatorward side of species ranges.The findings show that large-scale changes in the abundance of species are well underway. They also suggest that marine species haven't managed to adapt to warmer conditions. The researchers therefore suggest that projected sea temperature increases of up to 1.5°C over pre-industrial levels by 2050 will continue to drive the latitudinal abundance shifts in marine species, including those of importance for coastal livelihoods."This matters because it means that climate change is not only leading to abundance changes, but intrinsically affecting the performance of species locally," Genner says. "We see species such as Emperor penguin becoming less abundant as water becomes too warm at their equatorward edge, and we see some fish such as European seabass thriving at their poleward edge where historically they were uncommon."The findings show that climate change is affecting marine species in a highly consistent and non-trivial way. "While some marine life may benefit as the ocean warms, the findings point toward a future in which we will also see continued loss of marine life," Genner says.The long-term data included in the study primarily represent the most well-studied regions of the world. The researchers say that more work is needed to understand how climate change has affected marine life in all regions of the world in greater detail."We aim to get a better understanding of precisely how marine climate change drives abundance shifts," Genner says. "Is this mainly related to the physiological limits of the species, or instead due to changes in the species with which they interact?"The work was supported by the Natural Environment Research Council and the UK Government Office for Science.
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New Species
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March 25, 2020
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https://www.sciencedaily.com/releases/2020/03/200325131537.htm
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Here be dragons: Analysis reveals new species in 'Smaug' lizard group
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Smaug, the deadly dragon in J.R.R Tolkien's "The Hobbit," has a few living relatives. With dense, alligator-like armor, these small, real-life dragon lizards are rock-crevice recluses mostly confined to mountaintops in southern Africa.
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Now, herpetologists Michael Bates, a curator at South Africa's National Museum in Bloemfontein, and Edward Stanley of the Florida Museum of Natural History have discovered a ninth species of dragon lizard in the genus Smaug, previously mistaken for a similar-looking species, The new species, a heavily plated dark brown lizard with pale yellow bands, has been named Smaug swazicus, or the Swazi dragon lizard, in honor of the country of Eswatini, where most of the species' range is located. Up to 13 inches from snout to tail tip, "In terms of bulk and actual recorded total length, Smaug swazicus may be the largest southern African lizard species described since the western giant plated lizard, Matobosaurus maltzahni, 82 years ago," Bates said.While species in the Smaug genus, also known as girdled lizards, may have scaled-down versions of their fearsome namesake's shield-like scales and sword-like teeth, they have gentle dispositions, Stanley said."They're just little tanks," said Stanley, who is also the director of the Florida Museum's Digital Discovery and Dissemination Laboratory. "They hide in rock cracks and put a lot of their energy and effort into simply being spiky and inedible, so they don't have to put up a big fight."Stanley led a group of scientists that named the Smaug genus in 2011, and he has been instrumental in parsing out its species. "Smaug," he explained, comes from the German word "smugan," which means "to squeeze through a hole." These lizards are also found near South Africa's Drakensberg Mountains, Afrikaans for "dragon mountains."While Africa has an enormous diversity of lizards, girdled lizards are the only family exclusive to mainland Africa and, because of their crevice-dwelling lifestyle, are often restricted to specific habitats. As a result, Stanley said more stringent conservation strategies may be needed for certain Smaug species."Tethered to high-elevation boulder-filled habitats, dragon lizards could already be feeling the effects of a warming climate, Stanley said. Securing rock crevices in which to hide could become challenging as dragon lizards creep to higher elevations in search of lower temperatures."These creatures are brilliantly evolved for their environment. If things aren't done to protect them, we could lose 20 million years of evolution in 50 years," he said. "The important thing is that you need to characterize and identify animals before you can protect them. You need to know what you have before you can make a plan to protect it."But finding lizards in southern Africa can be daunting: Stanley and his fellow researchers had to dodge everything from mambas to undetonated explosives. When team members expanded their search to well-shaded boulders on a military base, they were accused of being gold prospectors, thieves and pet trade dealers."We had to spend all morning explaining, 'No, we're not here for any of that -- we're really here just to try and find some lizards on your army base,'" Stanley said. "And in fact, because the range was so unpopulated, the lizards we found there were quite friendly. It was a weird experience having spent such a long time looking for them and then going into this sort of garden where they'd run on your lap and jump into your arms."Stanley's next run-in with the new species wasn't deep in the South African escarpment. He said he recognized the species from his time at the American Museum of Natural History, where there was a jar of unidentified pet trade specimens from the early 1980s in the herpetology collection."That's the nice thing about museums, isn't it? It's not like these animals are sitting underground, never before seen. A lot of times they're just hiding in plain sight," he said.To differentiate similar-looking species, Stanley and Bates relied on traditional approaches based on physical features, CT scanning and DNA analysis, a process he compared to sorting candy."Say you have different kinds of candies that you need to sort by type," Stanley said. "You start by visually sorting all your M&M's into one pile and your Mike and Ike's in another."Then comes the DNA analysis -- in other words, the taste test."So, you sample your candies, and you find that there are a proportion of M&M's you've sorted that are actually Skittles, and then you notice that instead of an 'M,' they actually have a tiny 'S' on them," Stanley said. "You can now pull these out and say, 'Oh, I actually have three candies.'"The new species of dragon lizard can be compared to the Skittles, Stanley said -- similar in appearance to Stanley said he can't rule out the possibility that more species in the group await discovery."Even now, in this well-worked group in these very populated countries of South Africa and Eswatini, that have had a lot of herpetologists working for hundreds of years, there are still some cool discoveries to be made," he said. "That's the biggest part of the story for me, is that there are some awesome animals out there just undescribed."
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New Species
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March 24, 2020
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https://www.sciencedaily.com/releases/2020/03/200324131845.htm
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All microgastrinae wasps from around the world finally together in a 1,089-page monograph
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With 3,000 known species and thousands more left to describe, the wasps of the subfamily Microgastrinae are the single most important group of parasitoids attacking the larvae of butterflies and moths, many of which are economically important pests. Consequently, these wasps have a significant impact on both the world's economy and biodiversity.
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Due to their affinities, these wasps are widely used in biological control programs to manage agricultural and forestry pests around the globe. Further, they have also been prominently featured in many basic and applied scientific research (e.g. chemical ecology, biodiversity studies, conservation biology, genomics, behavioural ecology). However, the information about Microgastrinae species is scattered across hundreds of papers, some of which are difficult to find. To make matters worse, there has never been an authoritative checklist of the group at a planetary scale.All currently available information about the group is now brought together in a large monograph of 1,089 pages, published in the open-access, peer-reviewed journal Moreover, the researchers have included extensive colour illustrations of all genera and many species (thousands of images in 250 image plates); brief characterisation and diagnosis of all genera; detailed species distributions (within biogeographical regions and per individual country); synopsis of what is known on host-parasitoid associations; summary of available DNA barcodes; estimations of the group diversity at world and regional levels; as well as notes on individual species upon request."Compiling this annotated checklist was, more than anything, a labour of love," says Dr. Jose Fernandez-Triana of the Canadian National Collection of Insects, lead author of the paper."For the past six or seven years, we have spent thousands of hours pouring through hundreds of publications, reading original descriptions in old manuscripts, checking type specimens in many collections worldwide, exchanging information with colleagues from all continents. For the past year or so, I basically stopped all other ongoing research projects I was involved with, to focus solely (almost obsessively!) on finishing this manuscript. The work was often tedious and mind-numbing, and many times I had the temptation to delay the completion of the paper for a later time. However, I was lucky that the other co-authors were just as passionate as myself, and we all pushed each other to finish the task when energy ran low," comments Dr. Fernandez-Triana."For the past few years, the Microgastrinae wasps have been one of the most intensively studied groups of insects, at least from a taxonomic perspective," he adds. "Just to give you an idea: between 2014 and 2019 a total of 720 new species of Microgastrinae were described worldwide. That is an average of one new species every three days, sustained over a six-year period and showing no signs of slowing down."He also points out that many scientists from many different countries and biogeographical regions have been involved in the description of the new species. The paper recognises them all and their contributions in the Acknowledgements section."You could even say that we are witnessing a renaissance in the study of this group of wasps. However, even then, what has been done is only the tip of the iceberg, as we estimated that only 5 to 10% of all Microgastrinae species have been described. That means that we do not have a name, let alone detailed knowledge, for 90-95% of the remaining species out there. Perhaps, there could be up to 50,000 Microgastrinae wasp species worldwide. It is truly humbling when you consider the magnitude of the work that lies ahead."Yet, it is not only a matter of counting huge numbers of species. More importantly, many of those species either have already been put in use as biocontrol agents against a wide range of agricultural and forestry pests, or have the potential to be in the future.For applied scientists, working with hyperdiverse and poorly known groups such as Microgastrinae is even more perplexing. Navigating the maze of old names, synonyms (species described more than one time under different names), homonyms (same names applied to different species), or unavailable names (names that do not conform to the rules of the International Commission of Zoological Nomenclature) is a daunting task. Often, that results in the same species being referred to in several different ways by different authors and academic works. Consequently, many historical references are full of misleading or even plainly wrong information. Meanwhile, it is very difficult to seek out the useful and correct information.The present annotated checklist could work as a basic reference for anyone working with or interested in the parasitoid wasps of the subfamily Microgastrinae. In the future, the authors hope to produce revised editions, thus continuing to incorporate new information as it is generated, and to also correct possible mistakes."We welcome all kinds of criticisms and suggestions," concludes Dr. Fernandez-Triana. "And we hope that biocontrol practitioners will also help us, the taxonomists, to improve future versions of this work. However, for the time being, let me say that it is a tremendous relief to get this first version out!"
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March 24, 2020
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https://www.sciencedaily.com/releases/2020/03/200324090010.htm
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Is Niagara Falls a barrier against fish movement?
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New research shows that fishes on either side of Niagara Falls -- one of the most powerful waterfalls in the world -- are unlikely to breed with one another. Knowing how well the falls serves as a barrier to fish movement is essential to conservation efforts to stop the spread of invasive aquatic species causing ecological destruction in the Great Lakes. The study is published today in the journal
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"In the past 50 years or so, aquatic invasive species have expanded in the Great Lakes as a tremendous conservation concern, causing billions of dollars' worth of damage," said Nathan Lujan, lead author of the study and a Gerstner Scholar at the American Museum of Natural History. "Both Canadian and American authorities are concerned about the potential impact of these species on the Great Lakes and are very interested in installing barrier technologies in the Niagara River that would slow or stop their spread."For more than 11,000 years since glaciers retreated from North America, most water flowing through the Great Lakes has crossed the Niagara Falls, which has a flow rate of more than 750,000 gallons per second. There's one other way water can get through this constriction point: through the Welland navigation canal, which was built about 200 years ago and features a series of locks that bring vessels from one side of the falls to the other. The canal is relatively small compared to the Niagara River, but questions remain about how significant it and the falls are in allowing fishes to move upstream to downstream, and vice versa. The leading idea is to install a combination of barrier technologies in the Welland Canal, including electricity, sound, light, and possible physical barriers to inhibit fish movement."If you're going to spend potentially hundreds of millions of dollars on installing barrier technologies and fishes can go right over the falls, then that's obviously not a good use of resources," Lujan said. "If people can survive it in a barrel, you'd think a fish could."To investigate these questions, Lujan and colleagues examined the DNA of seven native fish species to determine whether populations above and below Niagara Falls interbreed or are reproductively isolated. By gathering data from throughout the fishes' genomes, they found that populations of all species are genetically distinct on opposite sides of the falls.Then they modeled how DNA from different populations mix, and determined that in four species there has been no significant migration past Niagara Falls since the falls were first formed 11,000 years ago. Two other species showed some indication of migration past the falls, yet the models indicated that no species had migrated past the falls via the Welland Canal."These results should reassure policymakers that infrastructure being considered to prevent the movement of invasive aquatic species will not impact native species, and that the falls themselves are an effective barrier to both upstream and downstream movement of aquatic species," Lujan said. "Additional measures to prevent fish movement can safely be restricted to the Welland Canal."
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March 23, 2020
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https://www.sciencedaily.com/releases/2020/03/200323132408.htm
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Which forests in Borneo are most in need of protection?
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An international team of researchers, including two from the University of Montana, are working to help identify priority forest areas for protection on Borneo.
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The government of the state of Sabah in Malaysian Borneo has set an ambitious target of securing 30% of Sabah's land area under protection by 2025. The study identified important forest areas across the state that are critical for protection. These areas are rich in threatened rainforest animals and plants. The forests also store large amounts of carbon, helping to slow global warming.In total, the priority forests identified are about the size of Glacier National Park, almost twice the size of the Yorkshire Dales National Park in the United Kingdom.Lead author, Dr. Sara Williams from UM said, "What makes our study different is that the research is being used to inform conservation planning decisions about to be taken by government agencies."The priority forest areas account for 5% of the land area of the state of Sabah. The approach that we came up with, selecting areas for protection strategically rather than randomly, protects around 12% of most of the statewide conservation features that we were interested in, which includes species ranges, forest carbon and landscape connectivity."Creating land corridors that link protected areas together will mean animals can move from the large parks across the Indonesian border into the flagship conservation areas in the center of Sabah."Allowing species to move from the hottest lowland areas to the cooler mountains will be especially important for conserving rainforest species in the long term, as they will need to keep up with a warming climate," said Dr. Sarah Scriven from the University of York.UM's Dr. Jedediah Brodie said, "Protected areas are generally situated based on scenic beauty or political expediency. But putting new protected areas in the best places for biodiversity, as we've done here, more than doubles their conservation benefits."
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March 23, 2020
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https://www.sciencedaily.com/releases/2020/03/200323085220.htm
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Vibes before it bites: 10 types of defensive behavior for the false coral snake
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In a recent paper in the open-access journal
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Evolution shaped anti-predator mechanisms in preys, which can be displayed either with avoidance or defensive behaviours. The current knowledge about such mechanisms are still scarce for many snake species, but it is constantly increasing over the last years. These data are helpful for better understanding of the species ecology, biology and evolution.The False Coral Snake (However, these behaviours were only a small part of what this species is capable of doing to defend itself! In November 2017, a juvenile male captured in the Atlantic Forest of southeastern Brazil was observed under laboratory settings, where the scientists would simulate a predation attempt with an increasing threat level."We released the snake on to the laboratory bench and let it notice our presence. The animal remained motionless at first, then performed a pronounced dorsoventral flattening of the anterior part of the body, raised its tail, adopted an S-shaped posture, raised the first third of the body and performed brief body vibrations. Then we approached the snake, which remained with the same posture and body vibrations. When we touched the animal (not handling), it remained with the S-shaped posture, keeping the first third of the body elevated and the dorsoventral flattening (however, less accentuated) and started to display erratic movements, false strikes and locomotor escape. When handled, the snake only struggled," shares the lead scientist Mr. Clodoaldo Lopes de Assis.Amongst ten recorded behaviour types only three were among those already registered for this species. Since defensive responses in snakes decrease as body size increases, juveniles exhibit a broader set of defensive behaviour than adults. Because of that, some types of behaviour described in this study might be explained either by physical constraints or stage of development of the individual.Some types of behaviour resemble the ones of true coral snakes of the genus Micrurus, a group of extremely venomous snakes. Thus, this similarity may be linked with the mimicry hypothesis between these two groups, where harmless false coral snakes take advantage of their similar appearance to the true coral snakes to defend themselves.Another type of anti-predation mechanism shown -- body vibrations -- is yet an unknown behaviour for Brazilian snakes and has been recorded for the first time. This type of behaviour is difficult to interpret, but could represent a defensive signal against non-visually orientated predators.Finally, defensive strategies of the specimen differed according to the threat level imposed: starting from discouraging behaviour up to false bites, erratic movements and locomotor escape.""Through such simple laboratory observations we can get a sense of how Brazilian snakes are yet poorly known regarding their natural history, where even common species like the false coral snake
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March 23, 2020
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https://www.sciencedaily.com/releases/2020/03/200323112053.htm
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Christmas Island discovery redraws map of life
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The world's animal distribution map will need to be redrawn and textbooks updated, after researchers discovered the existence of 'Australian' species on Christmas Island.
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The University of Queensland's Professor Jonathan Aitchison said the finding revises the long-held understanding of the location of one of biology and geography's most significant barriers -- the Wallace line."The Wallace line -- named after its discoverer Alfred Russel Wallace -- delineates major biological division separating the species with Asian origins from those with Australasian ones," Professor Aitchison said."It runs along the narrow seaways separating Bali from Lombok, and Borneo from Sulawesi."To the west are the tigers, elephants, rhinoceroses and orang-utans of Eurasia and to the east, the marsupials and monotremes that are synonymous with Australia."Working 1000 kilometres west of the conventional trace of Wallace line, on Christmas Island, Professor Aitchison and his colleagues, Dr Jason Ali from the University of Hong Kong and Professor Shai Meiri from the University of Tel Aviv, noted species with Australasian origins."Unexpectedly, half of Christmas Island's land mammal and land reptile species -- two rats, two skinks and one gecko -- have a genetic heritage to Australia's side of the divide," Dr Ali said."It was a highly surprising discovery."The ancestors of these species would have most likely have been washed over on uprooted trees of vegetation mats and transported in by a major oceanic current known as the Indonesian Throughflow."The Indonesian Throughflow is part of the global heat conveyor belt, and follows deeper waters that delineate the Wallace line."It's caused by the westernmost Pacific Ocean surface topography being slightly higher than its Indian Ocean counterpart."That's right -- it's a little mind-bending -- but the 'sea-level' varies slightly in different parts of the world."Professor Aitchison said the species' journey must have occurred within the last five million years, as this is when Christmas Island emerged to form a new landmass."Christmas Island existed as a coral atoll from about 40 to 17 million years ago," Professor Aitchison said."But in response to a tectonics phenomenon originally described by Darwin, it subsided beneath the ocean surface and disappeared."It re-surfaced only five million years ago thanks to some flexing tectonic plates -- 300 to 350 kilometres to the south of where it is now located -- from then on land plants and animals could begin to establish new populations."Christmas Island is a strange and unique place, not just because of its geological history, but also its biological history."We're excited to see what other weird and wonderful discoveries are ahead."
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March 18, 2020
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https://www.sciencedaily.com/releases/2020/03/200318143725.htm
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Heatwaves risky for fish
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Scientists using sophisticated genetic analysis techniques have found that some fish are better than others at coping with heatwaves.
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A world-first study tracked how wild fish populations responded to a severe marine heatwave, focussing on the 2016 event that killed a third of the Great Barrier Reef corals."Our study shows that reef fishes are directly affected by heatwaves, but their responses vary greatly between species," said co-author Dr Jodie Rummer, Associate Professor from the ARC Centre of Excellence for Coral Reef Studies at James Cook University (Coral CoE at JCU).Dr Rummer was part of an international team that tracked changes in the expression of thousands of different genes in five species of coral reef fishes collected at different time points before, during, and after the 2016 heatwave."Changes in gene expression can tell us how an animal responds physiologically to an environmental shock, such as a heatwave," said one of the co-lead authors, Dr Celia Schunter from the University of Hong Kong.Regulating gene expression is critical to an organism's performance and survival.It is analysed by tracking RNA, which is responsible for converting the genetic information in DNA into a format used to build proteins.Essentially, RNA controls when proteins are made and in what amount, dictating how cells will function. This can give us clues of how an organism is responding.The scientists identified species-specific responses to the heightened temperatures, with some fish struggling more than others."Spiny damselfish responded to the warmer conditions with changes in the expression of thousands of genes, suggesting it is particularly sensitive to heatwaves," said co-lead author Dr Moisés Bernal, Assistant Professor at Auburn University. "Other species appear to be more tolerant, with fewer changes in gene expression."The results also suggest that fish populations are influenced by both the intensity of a heatwave and how long it lasts."Marine heatwaves are becoming more frequent, more severe, and are further exacerbated by climate change," Dr Rummer said."We found the physiological mechanisms the fish used to cope with the warmer waters changed as the heatwave progressed," she said.The study provides a possible approach for predicting which fish species are most at risk under repeated heatwave conditions, said co-author Professor Timothy Ravasi, from the Marine Climate Change Unit at the Okinawa Institute of Science and Technology Graduate University (OIST)."Our results are important because they show that when scientists do experiments, or target commercial species, they cannot generalise based on geography or from one or two species that have been studied in the laboratory," he said."This has ramifications for policy makers and for the fishing industry, because not all species will be equally affected. We need to screen a large number of species to predict which will be sensitive and which will be more tolerant to warming waters and heatwaves.""Over time, the fish may adapt to rising temperatures, or even migrate to cooler waters," Dr Rummer said."But these heatwaves are happening now, and it's necessary to understand and consider the immediate consequences."
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March 18, 2020
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https://www.sciencedaily.com/releases/2020/03/200318143719.htm
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New species of sawsharks found in West Indian Ocean
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Not one, but TWO new species of the rarely seen six-gilled sawsharks have been found in the West Indian Ocean by an international team of marine scientists.
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The newly discovered Publishing their findings today in the journal Lead author Dr Simon Weigmann, based at the Elasmobranch Research Laboratory in Hamburg, explained:"The six-gill sawsharks are really quite extraordinary as most sawsharks have five gill slits per side."So it was really exciting to find a new six-gill sawshark species and to find two new species -- well that was simply astonishing!"Knowledge of sawsharks in the western Indian Ocean is generelly still scarce. But considering their known depth distributions, both new species are likely affected by fishing operations."This assumption, combined with the limited range and apparent rarity of both new species, raises concerns that they are vulnerable to overfishing and might be in continuing decline."This could be particularly alarming for Anna's six-gill sawshark due to its very small known range, rarity and occurrence in shallow waters as the species is only known from depths of 20 to 35 m."Two rostra of Dr Temple, a co-author on the paper, said:"Last year our team highlighted the massive underreporting of sharks and rays caught in the South West Indian Ocean and the urgent need to expand efforts globally to assess the impact of these fisheries on vulnerable species."The discovery re-enforces both how important the western Indian Ocean is in terms of shark and ray biodiversity, but also how much we still don't know."Dr Berggren, a co-author on the paper and leader of Newcastle's Marine MEGAfauna lab, adds:"This project is also testament to the value of scientists working with local communities. Without the fishers help we would not have discovered these animals. Their knowledge of their environment is unparalleled and it is our mission to help them preserve the marine animals and ecosystems they rely on to survive."As its name suggests, the sawshark is a type of shark best known for its saw-like snout. Found mainly in the temperate waters of all three major oceans (with the centre of distribution in the western Pacific Ocean), the number of sawsharks has declined in the past couple of decades due to commercial fishing.Sawsharks can reach up to about 1.5 metres in length and have a long snout edged with sharp teeth which alternate in size (smaller teeth are inserted between larger teeth).They also has a distinctive pair of barbels in the middle of the snout -- whisker-like sensory organs around the shark's mouth which help the shark detect its prey.Even though the sawshark and sawfish share similarities in appearance, they differ in several aspects. Sawfish are larger, they don't have barbels, and their gills are located on the bottom side of the body (like typical for rays).Sawsharks are carnivores, living on a diet of fish, crustaceans and squid, and use their serrated snout to kill their prey. Fast movement of the snout from side to side cuts the prey into fine pieces that can be swallowed easily.Both new species differ from the only previously known six-gill species, A special feature of
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March 17, 2020
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https://www.sciencedaily.com/releases/2020/03/200317105529.htm
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Mysterious ancient sea-worm pegged as new genus after half-century in 'wastebasket'
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When a partial fossil specimen of a primordial marine worm was unearthed in Utah in 1969, scientists had a tough go identifying it. Usually, such worms are recognized and categorized by the arrangement of little knobs on their plates. But in this case, the worm's plates were oddly smooth, and important bits of the worm were missing altogether.
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Discouraged, researchers placed the mystery worm in a "wastebasket" genus called That all changed recently when Paul Jamison, a teacher from Logan, Utah, and private collector, and his student Riley Smith were hunting fossils in the Spence Shale in Utah, a 506-million-year-old geologic unit housing a plethora of exceptionally preserved soft-bodied and biomineralized fossils. (Paleontologists call such a mother lode of fossils a "Lagerstätte.") There, Smith discovered a second, more thoroughly preserved example of the worm.Eventually, thanks to Jamison's donation, the new fossil specimen arrived at the University of Kansas Biodiversity Institute, where Anna Whitaker, a graduate student in museum studies, researched and analyzed the worm with scanning electron microscopes, energy-dispersive X-ray spectrometry and optical microscopy.At last, Whitaker determined the worm represented a new genus of Cambrian sea worm heretofore unknown to science. She's the lead author of a description of the worm just published in the peer-reviewed paleontological journal "Before the new species that we acquired there was only one specimen known from the Spence Shale," she said. "But with our new specimen we discovered it had characteristics that the original specimen didn't have. So, we were able to update that description, and based on these new characteristics -- we decided it didn't fit in its old genus. So, we moved it to a new one."Whitaker and her colleagues -- Jamison, James Schiffbauer of the University of Missouri and Julien Kimmig of KU's Biodiversity Institute -- named the new genus Utahscolex."We think they're closely related to priapulid worms that exist today -- you can find them in the oceans, and they are very similar to priapulids based on their mouth parts," Whitaker said. "What's characteristic about these guys is that they have a proboscis that can evert, so it can turn itself inside out and it's covered with spines -- that's how it grabs food and sucks it in. So, it behaved very similarly to modern priapulid worms."While today, Utah is not a place you'd look for marine life, the case was different 506 million years ago, when creatures preserved in the Spence Shale were fossilized."The Spence Shale was a shelf system, and it's really interesting because it preserves a lot of environments -- nearshore to even deeper offshore, which is kind of unusual for a Lagerstätte, and especially during the Cambrian. These animals were living in kind of a muddy substrate. This worm was a carnivore, so it was preying on other critters. But there would have been whole diversity of animals -- sponges, and trilobites scuttling along. We have very large, for the time, bivalve arthropods that would be predators. The Spence has a very large diversity of arthropods. It would have looked completely alien to us today."Whitaker hopes to complete her master's degree this spring, then to attend the University of Toronto to earn her doctorate. The description of Utahscolex is Whitaker's first academic publication, but she hopes it won't be her last. She said the opportunity to perform such research is a chief reason for attending KU."I came for the museum studies program," she said. "It's one of the best in the country, and the program's flexibility has allowed me to focus on natural history collections, which is what I hopefully will have a career in, and also gain work experience in the collections and do research -- so it's kind of everything I was looking for in the program."While ancient sea worms could strike many as a meaninglessly obscure subject for such intense interest and research, Whitaker said filling in gaps in the fossil record leads to a broader understanding of evolutionary processes and offers more granular details about the tree of life."I know some people might say, 'Why should we care about these?'" she said. "But the taxonomy of naming all these species is really an old practice that started in the 1700s. It underpins all the science that we do today. Looking at biodiversity through time, we have to know the species diversity; we have to know as correctly as we can how many species there were and how they were related to each other. This supports our understanding of -- as we move into bigger and bigger, broader picture -- how we can interpret this fossil record correctly, or as best we can."
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March 17, 2020
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https://www.sciencedaily.com/releases/2020/03/200317103828.htm
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Botany: Major advances in our understanding of New World Morning Glories
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A major advance in revealing the unknown plant diversity on planet Earth is made with a new monograph, published in the open-access, peer-reviewed journal
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The family of morning glories, also known as bindweeds, whose scientific name is Convolvulaceae, includes prominent members like the sweet potato and ornamental plants such as the moonflower and the blue dawn flower. In fact, one of the key conclusions, made in the present work, is that within this plant group there are many other species, besides the sweet potato, that evolved storage roots long before modern humans appeared on Earth. Furthermore, most of those are yet to be evaluated for economic purposes.To make their findings, the research team of John Wood, Dr Pablo Muñoz Rodríguez, Bethany R.M. Williams and Prof Robert Scotland applied the "foundation monograph" concept that they had developed for similarly diverse and globally distributed, yet largely understudied groups. Usually, such groups with hundreds of species have never been surveyed across their entire geographical range, which in turn results in the existence of many overlooked new species or species wrongly named.As a result, the monograph adds six new to science species and establishes nine new subspecies, previously recognised as either distinct species or varieties. The publication also cites all countries where any of those 425 morning glories occurs. In order to provide detailed knowledge about their identities and ecologies, the authors also produced over 200 illustrative figures: both line drawings and photos.In their study, the scientists also investigate poorly known phenomena concerning the genus. For instance, the majority of the plants appear to originate from two very large centres, from where they must have consequently radiated: the Parana region of South America and the Caribbean Islands. Today, however, a considerable amount of those species can be found all around the globe. Interestingly, the team also notes a strong trend for individual species or clades (separate species with a common ancestor) to inhabit disjunct localities at comparable latitudes on either side of the tropics in North America and South America, but not the Equator.The monograph exemplifies the immense value of natural history collections. Even though the researchers have conducted fieldwork, most of their research is based on herbarium specimens. They have even managed to apply DNA sequencing to specimens over 100 years old. The publication also provides detailed information about the characteristics, distribution and ecology of all the species. It is illustrated with over 200 figures, both line drawings and photos."A major challenge in monographing these groups is the size of the task given the number of species, their global distribution and extensive synonymy, the large and increasing number of specimens, the numerous and dispersed herbaria where specimens are housed and an extensive, scattered and often obscure literature," comment the scientists."Unlike traditional taxonomic approaches, the 'foundation monograph' relies on a combination of standard techniques with the use of online digital images and molecular sequence data. Thereby, the scientists are able to focus on species-level taxonomic problems across the entire distribution range of individual species," they explained.
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March 12, 2020
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https://www.sciencedaily.com/releases/2020/03/200312163834.htm
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A new use for museum fish specimens
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The discoloured fish that rest in glass jars in museums across the world are normally used by specialists as references to study the traits that identify certain species. But a new study proposes an additional use for such 'samples.'
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Published in the "The length-weight relationship of fish, which allow computing the weight from their length, is something marine biologists need for a wide variety of studies. For example, they need them when they are estimating the biomass of certain species by performing visual census either by scuba diving or by using remote observation vehicles or underwater video stations," said Amanda Hay, lead author of the study and a researcher at the Australian Museum Research Institute.But some fish like those that live in deep waters are so difficult to reach and observe that a museum specimen may be the only known representative of the species. "This is why it is so important to 'extract' as much information as possible from that individual," Hay said.When live fish are hard to catch for the researchers who study them, the most common practice is to assume that their biological traits equate to those of similar species. Using preserved fish specimens, however, is a more precise way to learn more about elusive species.The proof of concept prepared by Hay and her colleagues at Canada's Beaty Biodiversity Museum and China's Institute of Oceanology involved measuring 56 preserved adult specimens of 31 species and uploading their results to FishBase, the largest online database on fish."FishBase has information for over 30,000 fish species but, of those, only 5,500 have length-weight parameters," said Daniel Pauly, co-author of the study and principal investigator of the The paper "The why and how of determining the length-weight relationships of fish from preserved museum specimens" was published today in the
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March 11, 2020
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https://www.sciencedaily.com/releases/2020/03/200311131025.htm
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The naming of the shrew
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Researchers at Louisiana State University have discovered a new species of shrew, which they have named the hairy-tailed shrew, or
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"There was no doubt that this was a new species," said LSU Museum of Natural Science Mammal Curator Jake Esselstyn whose work on Sulawesi Island in Indonesia led to the discovery published in the The newly discovered shrew is slender with gray-brown fur on its back and silver-gray fur on its belly. Its tail is slightly longer than the combined length of its head and body and is covered with long bristles and hair, which make the distinctive tail very hirsute. In fact, no other shrew species in Indonesia, Malaysia or the Philippines is known to have such thick, long hair on its tail; however, some shrew species in Africa have very hairy tails. The scientists were also surprised to discover that this shrew climbs trees whereas most shrews live primarily on the ground, as far as anyone knows.The Sulawesi hairy-tailed shrew was found on nine mountains across Sulawesi at various elevations from 1,500 feet to 4,800 feet."Tropical diversity is still not well documented even for mammals with a wide distribution on this island. This discovery shows how little we still know about mammal diversity," Esselstyn said.The real challenge was figuring out which shrew is its closest relative and how this new species fits into the shrew family tree. Shrews' features do not change very much over time, which means closely related species tend to look very similar and are hard to distinguish from each other. This has posed a challenge for mammalogists in the past to discover new shrew species."Genetic data have revolutionized what we can distinguish between shrews. A lot of species are first recognized as being genetically distinct, then we look at its morphology, or physical features," Esselstyn said.Deforestation and degradation of natural habitats have also posed a challenge for discovering new species. For example, a few shrew specimens were collected in the early 20th century, but when scientists return to the same location where the early specimens were collected, the habitat is no longer a forest. It is a farm.Despite these challenges, Esselstyn and his colleagues and students have also discovered several new mammals in Indonesia including the hog-nosed rat, the Sulawesi water rat and the slender root rat as well as the sky island moss shrew in the Philippines.Meanwhile at the LSU Museum of Natural Science, they continue to search and analyze specimens for more new species and to help put the pieces of the large tree of life puzzle together.
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March 11, 2020
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https://www.sciencedaily.com/releases/2020/03/200311100859.htm
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Single biological factor predicts distinct cortical organizations across mammalian species
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Researchers have explained how visual cortexes develop uniquely across the brains of different mammalian species. A KAIST research team led by Professor Se-Bum Paik from the Department of Bio and Brain Engineering has identified a single biological factor, the retino-cortical mapping ratio, that predicts distinct cortical organizations across mammalian species.
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This new finding has resolved a long-standing puzzle in understanding visual neuroscience regarding the origin of functional architectures in the visual cortex. The study published in In the primary visual cortex (V1) of mammals, neural tuning to visual stimulus orientation is organized into one of two distinct topographic patterns across species. While primates have columnar orientation maps, a salt-and-pepper type organization is observed in rodents.For decades, this sharp contrast between cortical organizations has spawned fundamental questions about the origin of functional architectures in the V1. However, it remained unknown whether these patterns reflect disparate developmental mechanisms across mammalian taxa, or simply originate from variations in biological parameters under a universal development process.To identify a determinant predicting distinct cortical organizations, Professor Paik and his researchers Jaeson Jang and Min Song examined the exact condition that generates columnar and salt-and-pepper organizations, respectively. Next, they applied a mathematical model to investigate how the topographic information of the underlying retinal mosaics pattern could be differently mapped onto a cortical space, depending on the mapping condition.The research team proved that the retino-cortical feedforwarding mapping ratio appeared to be correlated to the cortical organization of each species. In the model simulations, the team found that distinct cortical circuitries can arise from different V1 areas and retinal ganglion cell (RGC) mosaic sizes. The team's mathematical sampling model shows that retino-cortical mapping is a prime determinant in the topography of cortical organization, and this prediction was confirmed by neural parameter analysis of the data from eight phylogenetically distinct mammalian species.Furthermore, the researchers proved that the Nyquist sampling theorem explains this parametric division of cortical organization with high accuracy. They showed that a mathematical model predicts that the organization of cortical orientation tuning makes a sharp transition around the Nyquist sampling frequency, explaining why cortical organizations can be observed in either columnar or salt-and-pepper organizations, but not in intermediates between these two stages.Professor Paik said, "Our findings make a significant impact for understanding the origin of functional architectures in the visual cortex of the brain, and will provide a broad conceptual advancement as well as advanced insights into the mechanism underlying neural development in evolutionarily divergent species."He continued, "We believe that our findings will be of great interest to scientists working in a wide range of fields such as neuroscience, vision science, and developmental biology."
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February 27, 2020
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https://www.sciencedaily.com/releases/2020/02/200227114553.htm
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Baldness plant gene discovery reveals origin of hairy alpine plants
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Scientists have solved a puzzle that has long baffled botanists -- why some plants on high mountainsides are hairy while their low-lying cousins are bald.
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Alpine species of snapdragon have evolved to disable a gene that prevents those living at low altitudes from growing hairs on their stalks and leaves, researchers say.The small hairs may act like UV sunscreen to protect alpine plants growing in full sun on lofty, exposed cliffs, the team says. Low-lying plants might not need to make the hairs because of the relative abundance of shade in valleys.These insights could aid the production of useful chemicals secreted by the hairs of some plants, scientists say, including the antimalarial drug artemisinin, and the chemicals that give herbs and hops their flavours.Researchers from the University of Edinburgh identified the gene that controls hair production -- which they named the Hairy gene -- in snapdragons by breeding alpine and lowland species with each other.They found that the gene is switched off in alpine plants. It is switched on in low-lying species, which causes baldness by blocking the activation of sections of DNA involved in hair production, the team says.Their findings show that the first snapdragons -- which grew around 12 million years ago -- were bald, and that newer, alpine species evolved as a result of mutations that deactivated the gene.
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New Species
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February 25, 2020
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https://www.sciencedaily.com/releases/2020/02/200225122959.htm
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Adaptation: Competition and predation may not be the driving force scientists thought
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Species adapt to their local climates, but how often they adapt to their local communities remains a mystery. To find answers, researchers at McGill University and the University of British Columbia examined over 125 studies testing local adaptation in over 100 species of plants and animals in an article published in
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"Local adaptation occurs when a population evolves to better suit its local surroundings. We already know that environmental pressures like temperature and drought can drive adaptation, but the impact of living pressures like competition or predator-prey relationships is less clear," according to Anna Hargreaves, an assistant professor of biology at McGill University.By comparing transplant experiments that used relatively natural environments to ones that reduced stressors like weeds and predation, the researchers examined how often such interactions among species drive local adaptation.Surprisingly, they found that although the interactions strongly affected how well species grew, survived, or reproduced, interactions did not necessarily spur adaptation. "We expected experiments to show us stronger local adaptation when stressful interactions were left intact. But we found that it wasn't stronger or common in these cases -- except perhaps in the tropics," says Hargreaves.According to the researchers, this is intriguing evidence that interactions might be more evolutionarily important in the tropics. Evolutionary biologists have long speculated that species might drive each other's evolution more often in the tropics, given the amazing diversity of tropical species, but evidence supporting this theory has been sparse until now. The authors say more direct tests of what drives local adaptation, especially studies of tropical species, are needed before we truly understand how interactions between species influence local adaptation.
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February 21, 2020
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https://www.sciencedaily.com/releases/2020/02/200221135528.htm
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Fossilized wing gives clues about Labrador's biodiversity during the Cretaceous
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A fossilised insect wing discovered in an abandoned mine in Labrador has led palaeontologists from McGill University and the University of Gdańsk to identify a new hairy cicada species that lived around 100 million years ago.
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Maculaferrum blaisi, described in a study published in Alexandre Demers-Potvin, a Master's student under the supervision of Professor Hans Larsson, Director of the Redpath Museum at McGill, said that a single wing was sufficient to identify the family to which the insect belonged."We were easily able to demonstrate that the insect belonged to the Tettigarctidae family thanks to the pattern of the veins we observed on its wing," said Demers-Potvin, who is also a 2018 National Geographic Explorer.The genus name (Maculaferrum) is derived from the Latin words macula -- spot -- because of the spotted pattern found on parts of the wing and ferrum -- iron -- due to the high iron content of the red rocks found at the Redmond site. The species name -- blaisi -- is in honour of Roger A. Blais, who conducted the first survey of the Redmond Formation and of its fossils in 1957 while working for the Iron Ore Company of Canada."This gives us a better understanding of the site's insect biodiversity during the Cretaceous, a time before the dinosaurs were wiped out," Demers-Potvin added. "The finding also illustrates that rare species can be found at the Redmond mine and that it deserves the attention from the palaeontological community.""The find is exciting because it represents the oldest, diverse insect locality in Canada. It's also from an exciting time during an evolutionary explosion of flowering plants and pollinating insects, that evolved into the terrestrial ecosystems of today," said Larsson.
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New Species
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February 20, 2020
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https://www.sciencedaily.com/releases/2020/02/200220101113.htm
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Citizen scientists discover a new snail, name it after Greta Thunberg
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A new to science species of land snail was discovered by a group of citizen scientists working together with scientists from Taxon Expeditions, a company that organises scientific field trips for teams consisting of both scientists and laypeople. Having conducted a vote on how to name the species, the expedition participants and the local staff of the National Park together decided to name the mollusc Craspedotropis gretathunbergae. The species name honours the young Swedish activist Greta Thunberg for her efforts to raise awareness about climate change. The study is published in the open access journal
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"The newly described snail belongs to the so-called caenogastropods, a group of land snails known to be sensitive to drought, temperature extremes and forest degradation," says snail expert and co-founder of Taxon Expeditions, Dr. Menno Schilthuizen. All individuals were found very close to the research field station (Kuala Belalong Field Studies Centre) at the foot of a steep hill-slope, next to a river bank, while foraging at night on the green leaves of understorey plants.Citizen scientist J.P. Lim, who found the first individual of Greta Thunberg's snail says: "Naming this snail after Greta Thunberg is our way of acknowledging that her generation will be responsible for fixing problems that they did not create. And it's a promise that people from all generations will join her to help."The expedition team approached Ms. Thunberg who said that she would be "delighted" to have this species named after her.However, this is not the first time that Taxon Expeditions team names a species in honour of an environmental advocate. In 2018, they named a new species of beetle after famous actor and climate activist Leonardo DiCaprio. Mr. DiCaprio temporarily changed his profile photo on Facebook to the photo of "his" beetle to acknowledge this honour.
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New Species
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February 19, 2020
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https://www.sciencedaily.com/releases/2020/02/200219154432.htm
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Bacteria on the International Space Station no more dangerous than earthbound strains
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Two particularly tenacious species of bacteria have colonized the potable water dispenser aboard the International Space Station (ISS), but a new study suggests that they are no more dangerous than closely related strains on Earth. Aubrie O'Rourke of the J. Craig Venter Institute and colleagues report these findings in a new paper published February 19, 2020 in the open-access journal
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Shortly after the National Aeronautics and Space Administration (NASA) installed the water dispenser aboard the ISS in 2009, periodic sampling showed that two bacteria, To learn more about these bacteria, researchers sequenced the genomes of 24 strains collected from 2010 to 2014. All of the The researchers conclude that the two bacterial species living within the dispenser are no more dangerous than similar strains that might be encountered on Earth. In the event of an infection, the bacteria can still be treated with common antibiotics.The authors add: "Within each species, the 19
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New Species
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February 19, 2020
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https://www.sciencedaily.com/releases/2020/02/200219092528.htm
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Sweet beaks: What Galapagos finches and marine bacteria have in common
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The variety of finch species on the remote Galapagos Islands is the most prominent example for Charles Darwin's and Alfred R. Wallace's theory of evolution through natural selection. Galapagos finch species have developed distinct beak sizes and shapes and thereby have adapted to different food sources. This exemplifies how even closely related species can effectively make use of available resources, avoid competition and thus co-occur in the same habitat.
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This principle is not limited to macrofauna. It also applies in the realm of marine microbes, the scientists from Bremen now show. Satellite photos taken from coastal areas during warm seasons often show that the ocean is green rather than blue. This color originates from immense numbers of microscopic marine algae -- so-called algal blooms. Such blooms are transient: At some point, all nutrients are depleted and predators like protists and viruses have taken their share. The ensuing mass mortality of the algae leads to the release of large quantities of organic matter into the seawater, including algal polysaccharides. These algal sugars are one of the main food sources for heterotrophic marine bacteria.Scientists at the Max Planck Institute for Marine Microbiology in Bremen, Germany, have investigated the bacterial response to spring algal blooms off the island of Heligoland in the German Bight (southern North Sea) for more than a decade. A close-knit microbial community is recurrently abundant during spring blooms in most years. One of the most prominent community members is This is also reflected in the timing of the clade's occurrence. Different clades tended to show up at different bloom stages. "One clade of presumed first responders is characterized by small genomes with a pronounced protein but limited sugar degradation capacity. In contrast, another clade of presumed late responders has larger genomes and the capacity to utilize more complex polysaccharides," Avci continues. Another clade seems to be tied to presence of a specific algae (genus Chattonella). It is characterized by large genomes and has the most diverse sugar menu of all investigated Like Galapagos finches, these results exemplify how also closely-related clades of marine bacteria (here
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