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February 10, 2020
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https://www.sciencedaily.com/releases/2020/02/200210133213.htm
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Reimagining the link between space and species could boost wildlife conservation
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In the latest issue of
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"There's a problem in ecology that's been around since the 1920s called the 'species-area relationship,'" said Soberón, a University Distinguished Professor at the KU Biodiversity Institute and Department of Ecology & Evolutionary Biology. "Ecologists noticed that the more space you assemble, the more species you will discover. And that's a mathematical relationship."The "problem" is that there's not a clear understanding of why the increase in geographic space is always accompanied by an increase in the numbers of species in that space."This observed relationship is pretty universal," Soberón said. "You can do it for islands or continental masses, in the tropics or in temperate regions -- wherever you do a plot of area versus number of species you get an increasing line. But why? Most explanations are based on the idea that the more individuals you sample, the more likely it is that they belong to a different species."But Soberón's new approach to species-area relationship is different. Rather than performing a headcount of animals (or plants) within a given geographic area, the KU researcher proposes calculating the number of "Grinnellian niches," or conditions that support the existence of species in that area.He said the method, expressed by mathematical formulae, could offer a more accurate roll call of species."What I did was to apply a theory we have been developing here at KU for the last 10 years, which is called 'Grinnellian-niche theory,'" Soberón said. "Instead of concentrating on counting individuals, I explained this pattern in terms of the requirements of species for different climatic combinations. Different species have different climatic requirements, and if you can model that you can place the different requirements -- which are called 'niches' -- in environmental niche space. And when you increase the area you're looking at you are also increasing niche space. That's the bottom line."According to Soberón, examples of niches could include water availability or the right temperature range."Some species tolerate very hot weather -- some species require less hot weather," he said. "Some species can tolerate very dry environments; other species require water in different amounts. So, this combination of, say, from what lowest temperature to what highest temperature. From what driest environment to what wettest environment, from what acidity in the soil, and so on -- you derive these combinations of requirements, they're called niches."The new approach refines the understanding of the species-area relationship because it accounts for factors beyond simply the size of an area. For instance, Soberón said the Grinnellian-niche approach could account for variations in environment, such as temperature, that occur more powerfully north-to-south than east-to-west."Latitudinal effects are just one of the many things that conventional theories ignore," Soberón said. "But they play a very prominent role in the theory I've published, because it matters a lot whether you are moving, say, from Alaska to Central America, or vice versa. You encounter different species, different sets of tolerances and different niches. But in traditional theories, that doesn't matter because you just care about how much area -- the distinction is not made whether that's tropical area or temperate area or polar area. But for me that's a very major thing."To hone his theoretical approach, Soberón performed the Grinnellian analysis for North American mammals, then compared results with massive databases of known populations of species for the same region, subdivided into grids."There's an organization called the International Union for Conservation of Nature that has been convening meetings of experts from all over the world to draw the various distributions of terrestrial vertebrates -- mammals, birds, reptiles and amphibians," the KU researcher said. "We have databases which are publicly available with distributions, already established by these experts. This is the work of decades. In fact, anyone can download them. They are public. I chose to look at the mammals because, well, I am slightly familiar with mammals and I have friends that are very familiar with mammals and I could ask questions of them. So, I downloaded IUCN database, which I used to test -- and I also downloaded a GBIF (Global Biodiversity Information Facility) database, which is a huge database of observations of species. Those I used to do the calculations."Soberón said his new approach to biogeography could aid species conservation and species management across a spectrum of commercial and ecological efforts."It's a matter of universal concern, what species live in a particular place," he said. "Those species may be species of conservation interest -- maybe you don't want tigers to go extinct, or gorillas. But there are also species of economic interest for people. For instance, there are plagues and diseases of crops, and you don't want to have those in your fields. There are species that transmit diseases for people, for instance, mosquitoes. So, the general problem of 'why did you find this species in a particular place?' is important for people. We care about certain species, and we don't want to have other species near us. And this combination of the ones that we'd like to keep, and the ones that we don't want to be close to us, is an instance of this general problem that I am dealing with in the paper."
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February 10, 2020
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https://www.sciencedaily.com/releases/2020/02/200210104110.htm
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New world map of fish genetic diversity
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In a population of animals or plants, genetic diversity can decline much more quickly than species diversity in response to various stress factors: disease, changes to habitat or climate, and so on. Yet not much is known about fish genetic diversity around the world.
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Help on that front is now on the way from an international team of scientists from French universities and ETH Zurich. They have produced the first global distribution map for genetic diversity among freshwater and marine fish. Furthermore, they identified the environmental factors that are instrumental in determining the distribution of genetic diversity. Their study was recently published in the journal To begin their study, the researchers analysed a database that contained the data of over 50,000 DNA sequences representing 3,815 species of marine fish and 1,611 species of freshwater fish. From this sequence data, the scientists estimated the average genetic diversity in sections of bodies of water, each section measuring 200 square kilometres.Their analysis revealed that genetic diversity is unevenly distributed throughout marine and freshwater fish. The greatest genetic diversity was found among marine fish in the western Pacific Ocean, the northern Indian Ocean and the Caribbean. Among freshwater fish, genetic diversity was greatest in South America, but comparatively low in Europe.In addition, the researchers determined that temperature is a key factor influencing genetic diversity among marine fish: as the temperature rises, so does diversity. By contrast, the key determinants of genetic diversity in freshwater fish were the complexity of their habitat structure and how their habitats have changed over time.The researchers see their study as a tool in efforts to improve conservation of genetic diversity and in turn biodiversity. Their map makes it easier to detect hotspots of species and genetic diversity and to plan appropriate protective action. Maintaining the genetic diversity is crucial, say the researchers. "The more diverse a population's gene pool is, the higher the potential for adaptation to environmental changes," explains Loïc Pellissier, co-?lead author of the study and Professor at ETH's Institute of Terrestrial Ecosystems.Based on the findings, Pellissier predicts that fish populations will have potentially differing levels of adaptability in various areas of their range. "When setting up conservation areas, this characteristic has to be taken into account with respect to location, size and ecological connectivity," he says.Protective measures thus far have concentrated primarily on maintaining species diversity. For example, several years ago Switzerland launched a programme for monitoring species diversity within its borders, but Pellissier believes this is not enough. "If we want to protect our biodiversity, we also have to monitor the genetic diversity of populations. This is the only way to ensure that the pool of varied genetic material is large enough to enable the survival of species under changing environmental conditions," he explains.The current study was made possible by a large number of local researchers who sequenced DNA samples from fish and shared the data in a publicly accessible database (http://www.barcodinglife.org). "This is a clear demonstration of how important open data is for the global study of natural processes," Pellissier says.
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February 5, 2020
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https://www.sciencedaily.com/releases/2020/02/200205132303.htm
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Asian hornet invasion spreads to Northern Germany
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In early September 2019, an Asian hornet (
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Known to prey on many insects, including honey bees and other beneficiary species, the Asian hornet, which had already invaded parts of Southern and Central Europe, is a potential threat to apiculture and even to ecosystems.The first specimen was captured in south-western France in 2005 and started to spread quickly. Over the next years, it invaded large parts of France and regions of Spain, Portugal, Belgium, Italy, the Netherlands, Great Britain and south-western parts of Germany. The estimated invasion speed for France has been estimated at around 78 km/year, but in reality, the species spread might be occurring much faster due to anthropogenic factors.It's not yet clear if the collected Asian hornet belonged to an already settled population or it's rather the first record of a new invasion. Nevertheless, considering the fast invasion speed of the species and its relatively high climatic tolerance, it's quite possible that it had reached Hamburg on natural routes and now reproduces there.Even though other models suggest that the Hamburg area is not suitable for the species today, the new find might be a sign that the Asian hornet has begun spreading at a speed above that previously known and even in climatically less favourable regions."Therefore, the current find needs to be taken seriously, no matter if it is only a single specimen or a member of an established population," shares the lead researcher Martin Husemann from Centrum für Naturkunde, University of Hamburg.Invasive species are one of the great challenges in the modern world. Their occurrence can be considered as one of the key important ecological and evolutionary drivers.
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New Species
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January 31, 2020
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https://www.sciencedaily.com/releases/2020/01/200131114741.htm
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DNA extracted in museum samples can reveal genetic secrets
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DNA in preserved museum specimens can allow scientists to explore the history of species and humanities impact on the ecosystem, but samples are typically preserved in formaldehyde which can damage DNA and make very difficult to recover.
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Researchers have used a vortex fluidic device (VFD) to speed up DNA extraction from an American lobster preserved in formaldehyde -- with the results providing a roadmap for exploring DNA from millions of valuable and even extinct species in museums worldwide.Flinders PHD candidate Jessica Phillips says processing the preserved tissue from museum specimens in the VFD breaks apart proteins, releasing DNA which offers important historical genetic information."DNA extraction is achieved by processing the preserved tissue in an enzyme solution in the VFD. This enzyme breaks apart the proteins, releasing the DNA which can be analysed. By using the VFD we are able to accelerate this process from days to hours," says Ms Phillips."For 150 years these samples have been preserved in formaldehyde which can damage the DNA and also make DNA difficult to recover. We used mechanical energy in a vortex fluidic device (VFD) to accelerate the extraction by processing the preserved tissue in an enzyme solution in the VFD."This work is a collaboration between University of California, Irvine (UCI), The Department of Organismic and Evolutionary Biology at Harvard University, and Flinders University.Researchers say the results provide a roadmap for exploring DNA from millions of historical and even extinct species in museums worldwide.Research Chair of Clean Technology Research Professor Colin Raston says the work builds on the body of about 80 papers that his research group has published about the vortex fluidic device."Applications of the VFD are rapidly expanding, but this has only been possibly by internal collaboration. The DNA extraction application involved collaboration with two other research laboratories headed by Professor Greg Weiss at UCI and Professor Peter Girguis at Harvard.""We have only scratched the surface about what is possible for this device," says Professor Raston."
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New Species
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January 28, 2020
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https://www.sciencedaily.com/releases/2020/01/200128114644.htm
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Second of its kind 'sharpshooter' leafhopper from Brazil 'strikes' with its coloration
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When, in 2014, Brazilian researchers stumbled across a never-before-seen red-eyed leafhopper feeding inside the rosettes of bromeliads, growing in the restingas of southeastern Brazil, they were certain it was a one-of-a-kind discovery. Described as new-to-science species, as well as genus (
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Several years later, however, a team of entomologists from Universidade Federal do Rio de Janeiro carried out fieldwork in a mountainous area of southeastern Brazil and, as a result, another bromelicolous leafhopper species of the genus was discovered: Cavichiana alpina. Only, the new one appeared even more spectacular.The new species, described and illustrated in the open-access journal Slightly larger than the previously known In conclusion, the researchers explain that the peculiarity of the two known Cavichiana species is best attributed to a putative common ancestor that had likely once been widely distributed in southeastern and southern Brazil. Later, they speculate, a vicariant event, such as the uplift of the southeastern Brazilian mountain ranges during the latest Eocene and Oligocene, might have caused its diversification into two separate species.
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New Species
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January 21, 2020
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https://www.sciencedaily.com/releases/2020/01/200121133321.htm
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New species of antibiotic-resistant bacteria found in infected wound
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A hitherto unknown antibiotic-resistant bacteria species, in the same family as
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Knowing which bacteria cause infections, and which antibiotics are effective and ineffective against them, is crucial for treatment choices. Ignorance can have grave consequences, even from what are normally uncomplicated infections.How the new bacteria group was detected, with its novel genetic variant of antibiotic resistance, is described in a study published in the journal, Using a sample from this patient, the Clinical Microbiology laboratories at Sahlgrenska University Hospital in Gothenburg isolated the bacteria, which proved to belong to the family Enterobacteriaceae. Species identification, however, required further, more comprehensive investigations and analyses.Using Next Generation Sequencing (NGS) of the genome DNA, the researchers were then able to characterize and classify the new species. Moreover, it proved to belong to a completely new genus of bacteria.The bacteria concerned are most likely to have caused infections before and after they were detected in Kungälv Hospital, where the patient samples were taken in 2014. However, it is only now that the species has been identified and its more specific traits have become known.Francisco Salvà Serra, one of two first authors of the study, does research at the Culture Collection University of Gothenburg (CCUG) and the Centre for Antibiotic Resistance Research (CARe), at the University of Gothenburg."This is a clear example of how important it is to be able to identify the direct causes of an infection. If the bacteria are identified accurately, doctors can prescribe specific antibiotics rather than needing to rely on broad-spectrum antibiotics," Salvà Serra said."Broad-spectrum antibiotics favor the development of antibiotic resistance in bacteria, including those causing disease. By extension, this results in reduced potential for treating infectious diseases."Hedvig Engström Jakobsson, the senior researcher in charge of the study, works at the Department of Infectious Diseases at Sahlgrenska Academy, University of Gothenburg, and heads the Molecular Microbiology Unit at Sahlgrenska University Hospital.She emphasizes that next-generation sequencing has revolutionized DNA-based strategies for bacterial diagnosis and surveillance."This study called for many different analyses, in which the technology gave us both more extensive and more in-depth knowledge about the new bacterium and its classification than had been possible before," says Engström Jakobsson.The name proposed by the scientists for the bacteria species,
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New Species
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January 21, 2020
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https://www.sciencedaily.com/releases/2020/01/200121133315.htm
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Walking sharks discovered in the tropics
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Four new species of tropical sharks that use their fins to walk are causing a stir in waters off northern Australia and New Guinea.
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While that might strike fear into the hearts of some people, University of Queensland researchers say the only creatures with cause to worry are small fish and invertebrates.The walking sharks were discovered during a 12-year study with Conservation International, the CSIRO, Florida Museum of Natural History, the Indonesian Institute of Sciences and Indonesian Ministry of Marine Affairs and Fisheries.UQ's Dr Christine Dudgeon said the ornately patterned sharks were the top predator on reefs during low tides when they used their fins to walk in very shallow water."At less than a metre long on average, walking sharks present no threat to people but their ability to withstand low oxygen environments and walk on their fins gives them a remarkable edge over their prey of small crustaceans and molluscs," Dr Dudgeon said."These unique features are not shared with their closest relatives the bamboo sharks or more distant relatives in the carpet shark order including wobbegongs and whale sharks.The four new species almost doubled the total number of known walking sharks to nine.Dr Dudgeon said they live in coastal waters around northern Australia and the island of New Guinea, and occupy their own separate region."We estimated the connection between the species based on comparisons between their mitochondrial DNA which is passed down through the maternal lineage. This DNA codes for the mitochondria which are the parts of cells that transform oxygen and nutrients from food into energy for cells," Dr Dudgeon said."Data suggests the new species evolved after the sharks moved away from their original population, became genetically isolated in new areas and developed into new species," she said."They may have moved by swimming or walking on their fins, but it's also possible they 'hitched' a ride on reefs moving westward across the top of New Guinea, about two million years ago."We believe there are more walking shark species still waiting to be discovered."Dr Dudgeon said future research would help researchers to better understand why the region was home to some of the greatest marine biodiversity on the planet.Video:
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New Species
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January 15, 2020
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https://www.sciencedaily.com/releases/2020/01/200115191520.htm
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Male songbirds can't survive on good looks alone
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Brightly coloured male songbirds not only have to attract the female's eye, but also make sure their sperm can last the distance, according to new research.
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In the study, published today in the Royal Society journal Previous studies have focussed on a bird's appearance alone, but this is the first study that has looked at this together with the shape of the sperm, to understand if intense competition shapes both plumage (to compete before mating) and the sperm (to compete after mating).The team looked at 278 species of song bird from around the world and a combination of data on their plumage and the shape of their sperm, to see how they have evolved to ensure successful mating.The eye-catching plumage of some male songbirds has long been explained as a result of sexual selection: brighter males compete more successfully for mates, and leave more offspring, so evolution favours them. Female birds, by contrast, remain drab, because for them it is more important to be camouflaged on the nest.How much competition for mates a male song bird faces varies between species, and depends on factors such as the number of available females, how dense the population is, and other things such as the structure of the vegetation they are in.Dr Durrant said: "The intensity of sexual selection varies between species. If mate competition is really strong, not only are males really colourful and attractive, but they also need to have the best sperm too if they are going to compete."The 'midpiece' in the bird's sperm produces energy-containing molecules, called ATP, to power movement. Previously, experts thought that if the sperm had a large midpiece, it produced a lot of ATP, and the sperm 'swam' really quickly and got to the egg first. Whilst this is true in some species, it is not always the case and it is more likely that a large midpiece allows the sperm to last longer, rather than swim faster.Data on plumage from previous studies were used, together with data on the shape of sperm, for 278 species of song birds. The team found that males from species with more elaborate and colourful plumage, had longer sperm midpieces, which allows the sperm to last for a long time after the male mates with the female, who then stores it for when she is ready to release an egg."In a really competitive environment, lots of males are competing with each other for the female's attention, and there can be a high number that mate with the same female, and this is where sperm and how long it lasts is really important," said Dr Durrant."If a female bird mates with a number of males, she will keep the sperm until she is ready to release an egg. At this point, long-lived sperm can reactivate and fertilise the egg. So it is not enough to be colourful, you have to have the total package and produce sperm that can last."What we are seeing is what evolution has done to these species to solve the problem of competing for mates," adds Dr Durrant.
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New Species
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January 13, 2020
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https://www.sciencedaily.com/releases/2020/01/200113175644.htm
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The advantage of changing sex in fish population recovery
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Humans eat a lot of fish, in some areas of the world making up an essential part of our diet. Fishing can sometimes deplete fish populations to the point where the fish have difficulty reproducing and growing their numbers again. Establishing Marine Protected Areas (MPAs) that limit or eliminate fishing within their borders can help fish to replenish their populations. They can then be harvested when they venture outside the MPA, spilling out into surrounding waters where fishers benefit from the recovered abundance.
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Some fish species, however, recover their populations at different rates when fishing is eliminated inside MPAs. A new study in the Ecological Society of America's journal Most studies on population recovery within MPAs from overfishing have focused on fixed-sex species, where a female fish stays female its whole life and a male stays male: "I think this is because many MPA studies and many scientists assume that most fish species are single-sex," says Scott Hamilton, Associate Professor at Moss Landing Marine Laboratories and San Jose State University and co-author on the study. But many important fishery species are not fixed-sex, and instead have female fish change to male at some point in their life.Often, fisheries will only harvest fish over a certain size. Size-selective harvests will end up targeting and catching males because they are usually bigger, which then skews the population towards female. In species that can alter the sex ratio on their own by changing sex, how is their reproduction and long term population recovery affected by male harvesting?Researchers used computer simulations to investigate how different sex-changing fish populations respond under MPA no-fishing implementation and also under unprotected conditions. They additionally looked at the "when" and "why" different species change sex to see if that has an effect on recovery as well.Different sex-changing species can follow several rules or signals that prompt them to change sex. For instance, gag grouper change sex at a fixed size or age; once individual female reach a certain size, they transition. The California sheephead, however, follows different rules: large territorial males guard a mating territory of females and limit when those females change sex. In this scenario, only when a large male dies can a female fish transition to male and take over the territory.In the researchers' simulations involving these different kinds of sex-changing species, it appears the length of time for population recovery heavily depends on the degree to which abundant males are needed for reproduction, or the "mating function."For species like the gag grouper, a species that mates in large, group spawning events and changes sex only at a certain size or age, male harvesting is problematic. Not enough males are available to fertilize all the eggs produced by the females, and the females are not able to transition and replace the males until they grow big enough to do so. "In this case," Hamilton explains, "our findings indicate that a sex-changing species will likely respond more slowly and unpredictably to MPA implementation than fixed-sex species."For species like the California sheephead, however, the female-skewed ratio created by harvesting actually works to their favor. When males are taken, a female transitions and takes his place in a territory. Because this species reproduces in a harem-like style in which one male mates with many females each day, these fish are not dependent on having abundant males to regrow their population.It appears that as long as females readily replace males, and the reproduction rate remains high even with few males, a sex-changing species has an advantage in population recovery over a generic fixed-sex species. Conversely, a species in which many males are needed in their mating function, especially when females do not become male until they grow to a certain size, is at a disadvantage.The good news is that the researchers expect most sex-changing species are of the first, harem-style type. "Unfortunately," says Hamilton, "the mating functions are unknown for virtually all fishes, so much more empirical research is needed to better understand the shape of the mating function for more species, especially those that are targeted by fishing activities."
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December 31, 2019
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https://www.sciencedaily.com/releases/2019/12/191231125139.htm
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eDNA expands species surveys to capture a more complete picture
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Tiny bits of DNA collected from waters off the West Coast allowed scientists to identify more species of marine vertebrates than traditional surveys with trawl nets. They also reflect environmental shifts such as unusual ocean temperatures that affect the organisms present, new research shows.
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The findings published in "eDNA is adding details that we might not get any other way, and giving us a more complete picture," said Collin J. Closek, an Early Career Science fellow at the Center for Ocean Solutions at Stanford University. Closek is lead author of the paper with other scientists from Stanford University, University of California Santa Cruz, and NOAA's Southwest Fisheries Science Center.Marine life constantly sheds bits of genetic material into surrounding water. eDNA techniques capture that DNA from water samples and identify the species it comes from. New laboratory sequencing methods help scientists examine many samples at once. They have made eDNA an increasingly powerful tool for detecting the range of species that have passed through the water.In fact, Closek said that collecting water samples and archiving them can provide a lasting record of the DNA record at a particular place and time. This allows scientists to tap that data years later."This helps us most in identifying species distribution," said Elliott Hazen, a research ecologist at the Southwest Fisheries Science Center and coauthor of the study. "With rapid sampling at unprecedented scales, once we understand what it is telling us, we can get a lot of information about marine life across a large area relatively quickly."The method does not provide all the answers, though. For example, current eDNA sequencing results do not yet allow researchers to count the number or abundance of each species. They do not identify the age or size of the species represented. This means that eDNA will not replace traditional monitoring such as trawl or acoustic surveys any time soon.Closek and his colleagues worked aboard the NOAA Ship Reuben Lasker in 2016 and 2017. They joined NOAA Fisheries' Rockfish Recruitment and Ecosystem Assessment Survey, which has evaluated the California current forage community since 1983. The eDNA team collected 131 one-liter samples of water in roughly the same places where the ship deployed trawl nets. They collected samples of juvenile rockfish and other forage species. Observers aboard the ship also simultaneously counted the number of marine mammals and seabirds seen during daytime hours. The scientists then compared the results.It was the first survey of eDNA across such a wide geographic scale on the West Coast.The trawl surveys identified 28 types of fish over the two years, 11 of which were identified only in the trawl surveys and not by eDNA. By itself, eDNA identified 65 different marine vertebrates, both fish and marine mammals. Together eDNA and trawl surveys identified 80 different fish and marine mammals. They included baleen whales, porpoises, dolphins, seals and sea lions, said John Field, a research fisheries biologist at the Southwest Fisheries Science Center."The eDNA analysis detected both the fish and marine mammals in the habitats that we would expect to find them, which gives us greater confidence in the technology to provide accurate details of the species present across the ecosystem," he said. "It may sound basic, but this is an important step in validating this powerful new method of surveying marine life."Comparing 2016 to 2017, there were differences between the organisms present and their distribution. In 2016 the remnant warmth from a marine heat wave known as "the Blob" was dissipating. Unusual warm-water species were widely spread through West Coast waters.In 2017, more normal conditions returned. Many of those unusual organisms diminished and eDNA found greater differences between the marine vertebrates present in different areas. These results indicate that eDNA results can help track changes in the environment."We don't have the resources to survey everywhere for everything, and eDNA expands our reach," said Alexandria Boehm, a professor in the Department of Civil and Environmental Engineering at Stanford and senior author of the new study. "Now that we know that the methods are in some agreement, it validates the methods so that people feel more confident using eDNA."
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New Species
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January 8, 2020
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https://www.sciencedaily.com/releases/2020/01/200108074753.htm
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First sighting of Larsonella pumilus fish in Japan
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During a 2017 survey of deep-sea fauna off the coast of Seragaki in Onna Village, Okinawa, researchers found something unexpected: a small fish with a vibrant yellow body. Using a remotely operated vehicle, the animal was retrieved 214 meters beneath the surface of the East China Sea. It was later identified as Larsonella pumilus.
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This species of goby hadn't yet been documented in Japan, nor had it been found at such great depths. The species was given a new Japanese name, "Yuuna-haze," due to its distinctive color. Yuuna (Hibiscus tiliaceus) is an abundant flower in Okinawa, and a symbol of Onna Village.The finding and subsequent morphological and phylogenetic analysis of Larsonella pumilus represents a collaborative effort between the Okinawa Churashima Foundation Research Center, the Okinawa Churaumi Aquarium, and researchers in the Marine Genomics Unit at the Okinawa Institute of Science and Technology Graduate University (OIST). The results of their findings are published in "The goby is a diverse taxon, containing more than 2000 known species, most of which inhabit shallow seas, streams, rivers, and lakes -- not the deep sea," said Dr. Ken Maeda, a staff scientist at OIST and a co-author of the new study. "In fact, deep-sea gobies are difficult to find, and not much information is known about them."The Okinawan Larsonella specimen perished three months after it was collected. Maeda and his collaborators preserved a piece of muscle in ethanol for genetic analysis, then sequenced the species' mitochondrial genome.Upon studying the phylogenetic placement of the Larsonella genus, the scientists found that it was closely related to the Priolepis group -- another genus in the goby taxon. The phylogenetic study also suggested that Priolepis is a more complex group than scientists previously thought.Before it was found in Okinawa, reports of Larsonella pumilus emerged in Somalia, the Seychelles, in the Indian Ocean near Western Australia, in the western Central Pacific, and in Tonga and New Caledonia in the South Pacific. These fish were collected at depths ranging from 30-69 meters. The Larsonella pumilis found in Okinawa at 214 meters was the seventh reported finding of the species, and the deepest yet."Larsonella has been thought to be very rare, but now we think it's possible that the main habitat of this goby is deeper than we thought," said Maeda. "Prior morphological information about Larsonella was based solely on a single specimen collected off the coast of Somalia. This new Okinawan specimen will be valuable for future taxonomic research on this group."
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New Species
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December 11, 2019
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https://www.sciencedaily.com/releases/2019/12/191211145628.htm
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A new early whale, Aegicetus gehennae, and the evolution of modern whale locomotion
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A newly discovered fossil whale represents a new species and an important step in the evolution of whale locomotion, according to a study published December 11, 2019 in the open-access journal
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The fossil record of whale evolution tracks the transition from land-dwelling ancestors to ocean-dwelling cetaceans. Protocetids are a group of early whales known from the Eocene Epoch of Africa, Asia, and the Americas. While modern whales are fully aquatic and use their tails to propel themselves through the water, most protocetids are thought to have been semi-aquatic and swam mainly with their limbs. In this study, Gingerich and colleagues describe a new genus and species of protocetid, The new whale was discovered in 2007 in the Wadi Al Hitan World Heritage Site in the Western Desert of Egypt. It is the youngest-known protocetid, dating to around 35 million years ago, and is known from one exceptionally complete skeleton and a partial second specimen, making it among the best-preserved ancient whales. Compared with earlier whales, it has a more elongated body and tail, smaller back legs, and lacks a firm connection between the hind legs and the spinal column. These adaptations indicate an animal that was more fully aquatic and less of a foot-powered swimmer than its ancestors.The body shape of The authors add: "Early protocetid whales living 47 to 41 million years ago were foot-powered swimmers, and later basilosaurid and modern whales -- starting about 37 million years ago -- were tail-powered swimmers. The late protocetid
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New Species
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December 9, 2019
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https://www.sciencedaily.com/releases/2019/12/191209161314.htm
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Scientists accidentally discover a new water mold threatening evergreen trees
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Grown as Christmas trees, Fraser firs are highly prized for their rich color and pleasant scent as well as their ability to hold their needles. Unfortunately, they are also highly susceptible to devastating root rot diseases caused by water molds in the genus Phytophthora.
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Scientists in Connecticut were conducting experiments testing various methods to grow healthier Fraser trees when they accidentally discovered a new species of Phytophthora. They collected the diseased plants, isolated and grew the pathogen on artificial media, then inoculated it into healthy plants before re-isolating it to prove its pathogenicity."Once the organism was isolated, the presence of unusually thick spore walls alerted us that this may not be a commonly encountered species," said Rich Cowles, a scientist at the Connecticut Agricultural Experiment Station involved with this study, "and so comparison of several genes' sequences with known Phytophthora species was used to discover how our unknown was related to other, previously described species." In fact, they had discovered a new species altogether.The fact that these scientists so readily discovered a new species of Phytophthora infecting Christmas trees suggests that there could be many more species waiting to be discovered. Recognizing the greater biodiversity among this genus infecting Christmas trees is important. Transportation of infected nursery stock and chance encounters of different Phytophthora species in the field can lead to new hybrids arising, which can have different pathogenic characteristics than their parent species."Knowing how many and which species are present is important, not only for Christmas tree growers, but also for protecting our natural environment," Cowles adds.Also of note, this research was conducted using apples to do the initial isolation of Phytophthora, a method that dates back to 1931, demonstrating that old methods in plant pathology are still valid and useful. "Combining this robust old technique worked well with modern molecular biology methods to isolate, and then identify our unknown plant disease," according to Cowles.
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New Species
| 2,019 |
December 4, 2019
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https://www.sciencedaily.com/releases/2019/12/191204124552.htm
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Record-size sex chromosome found in two bird species
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Researchers in Sweden and the UK have discovered the largest known avian sex chromosome. The giant chromosome was created when four chromosomes fused together into one, and has been found in two species of lark.
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"This was an unexpected discovery, as birds are generally considered to have very stable genetic material with well-preserved chromosomes," explains Bengt Hansson, professor at Lund University in Sweden.In a new study, the researchers charted the genome of several species of lark, a songbird family in which all members have unusually large sex chromosomes. The record-size chromosome is found in both the Eurasian skylark, a species that is common in Europe, Asia and North Africa, and the Raso lark, a species only found on the small island of Raso in Cape Verde.According to the Lund biologists Bengt Hansson and Hanna Sigeman, who led the study, the four chromosomes have fused together in stages. The oldest fusion happened 25 million years ago and the most recent six million years ago. The four chromosomes that have formed the larks' sex chromosome have also all developed at some time into sex chromosomes in other vertebrates."The genetic material in the larks' sex chromosome has also been used to form sex chromosomes in mammals, fish, frogs, lizards and turtles. This indicates that certain parts of the genome have a greater tendency to develop into sex chromosomes than others," says Bengt Hansson.Why the two species have the largest sex chromosome of all birds is unclear, but the result could be disastrous lead to problems for female larks in the future. Studies of different sex chromosome systems have shown that the sex-limited chromosome, for example the Y chromosome in humans, usually breaks down over time and loses functional genes."Among birds, the females have a corresponding W chromosome in which we see the same breakdown pattern. As three times more genetic material is linked to the sex chromosomes of these larks compared to other birds, this could cause problems for many genes," says Hanna Sigeman, doctoral student at the Department of Biology, Lund University.
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New Species
| 2,019 |
December 3, 2019
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https://www.sciencedaily.com/releases/2019/12/191203082904.htm
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Female fish can breed a new species if they aren't choosy about who is Mr. Right
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Fish will mate with a species outside their own if the male's colouring is attractive enough or if the female can't see him properly, according to new research.
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Such 'mistakes' in mate choice can lead to the evolution of new species, an international team of scientists found. The group studied 2000 fish and analysed the DNA of more than 400 cichlid fish from two freshwater lakes in East Africa. They discovered more than 40 new species in Lake Mweru, which formed around one million years ago.Dr Joana Meier, an evolutionary biologist at St John's College, University of Cambridge, and lead author of the research published today (December 3 2019) in "The new species of cichlids adapted to use all the available food resources in the lake. Some feed on insect larvae, others zooplankton or algae. Some newly discovered fish are predators with large teeth, which we named 'large-tooth serranchromines'."Many people assume fish are all the same species because they all live in water. But there are 30,000 different species of fish and many of them are markedly different from each other. Expecting them to mate outside of their own species is like expecting a horse to mate with a cat because they both have four legs and a tail.Fossil records show fish have existed for more than 500 million years which makes them very old on the evolutionary scale. There are more than 1300 species of cichlids and many are popular aquarium fish. They are primarily freshwater fish and the majority of species are African, appearing in great diversity in the major African lakes where this 10-year study took place.Female cichlid fish choose their partner and in mating ritual tests in the lab, the team of international scientists discovered that under certain circumstances the females would choose a male from different species that had similar colouring to males from their own species. They also found that when the light conditions are poor, the females could not distinguish between males of their own species or from other species because they could not see their colours properly.This is what they determined happened a million years ago when the different species of fish mixed together when Lake Mweru was formed, sparking the evolution of 40 new species of fish.Dr Meier explained: "To diversify into different species, the cichlid fish needed the ecological opportunity provided by the new habitats of Lake Mweru, formed one million years ago, which is still considered to be recent in evolutionary terms! That more than 40 species utilising different food resources and habitats could evolve so rapidly is highly unusual."When Lake Mweru was formed it combined cichlid lineages from the Congo and the Zambezi. The cichlids from these different drainage systems then mated with each other. This could have been because when the lake formed, the water was very cloudy and they couldn't see colours properly so the females were not being as choosy about selecting a mate in their new environment. Mating between cichlids from different drainage systems produced very diverse offspring combining the genetic traits of both parental species."The so-called 'hybrid offspring' can feed on different things to their parents and invade new habitats -- like swimming into deeper areas of the lake. It is unclear whether all of the species will survive as they may compete with each other and die out.Dr Meier said: "Our research shows that hybridisation can fuel the evolution of new species which is a very novel finding. Hybridisation has traditionally been viewed as something bad because if species hybridise they can, over time, merge into a single species and you lose biodiversity or lose the local species. The melting pot of Lake Mweru gave us a rare opportunity to study interactions between evolving new species and showed that in a new environment with lots of ecological opportunity hybridisation can be a good thing that actually increases biodiversity."
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New Species
| 2,019 |
December 2, 2019
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https://www.sciencedaily.com/releases/2019/12/191202105552.htm
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New evolutionary insights into the early development of songbirds
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An international team led by Alexander Suh at Uppsala University has sequenced a chromosome in zebra finches called the germline-restricted chromosome (GRC). This chromosome is only found in germline cells, the cells that hold genetic information which is passed on to the next generation. The researchers found that the GRC is tens of millions of years old and plays a key role in songbird biology, having collected genes used for embryonic development.
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The ability to reproduce is a fundamental trait of all life. How reproduction has evolved and how it functions on a genetic level is therefore of great interest to evolutionary biologists. During the early development of an animal embryo, cells are divided into two major types, germline and somatic cells. Germline cells are present in the reproductive organs and hold genetic information which is passed on to the next generation, whereas somatic cells are the cells which make up the rest of the organism. Biologists have discovered that in some organisms, certain genes and repetitive DNA-sequences are eliminated when cells become either somatic or germline, which means that not all cells in an organism contain the same genome.In certain species, entire chromosomes are specific to the germline. One such chromosome in zebra finches is called the germline restricted chromosome (GRC). For the first time, an international team led by Alexander Suh at the Department of Ecology and Genetics at Uppsala University has performed a comprehensive genomic, transcriptomic, and proteomic analysis of the GRC in zebra finches. The GRC is the largest chromosome in the zebra finch genome and constitutes more than 10 percent of the genome."The GRC is a very strange chromosome. We found that some of its genes are repeated tens or even hundreds of times, whereas the somatic cells have only one gene copy." says Cormac Kinsella, one of the first authors of the study.By identifying specific genes and comparing them with genomic data from other species, the scientists could unravel the evolutionary history of the GRC. The results showed that the GRC is tens of millions of years old and likely present across all songbird species, which represent half of all bird species. The scientists also think that the GRC became an important factor in bird development because many genes associated with early embryonic development are found there. Because the GRC is not present in somatic cells, expression of its genes only affects germline cells thereby protecting somatic cells from possible negative effects."Because we found GRC expression on the RNA and protein level, we expect our evidence for selection acting on the GRC to become the starting point of further exciting discoveries." says Francisco Ruiz-Ruano, the other first author of the study.
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New Species
| 2,019 |
November 25, 2019
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https://www.sciencedaily.com/releases/2019/11/191125173447.htm
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Dinosaur skull turns paleontology assumptions on their head
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A team of researchers at the University of Alberta has unearthed a well-preserved Styracosaurus skull -- and its facial imperfections have implications for how paleontologists identify new species of dinosaurs.
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The skull was discovered by Scott Persons in 2015, then a graduate student in the Department of Biological Sciences, during an expedition in the badlands northwest of Dinosaur Provincial Park.Nicknamed Hannah, the dinosaur was a Styracosaurus -- a horned dinosaur over five metres in length with a fan of long horns. UAlberta paleontologists led by Robert Holmes, professor in the Department of Biological Sciences, have learned much from those horns -- because they aren't symmetrical."When parts of one side of the skull were missing, paleontologists have assumed that the missing side was symmetrical to the one that was preserved," explained Persons. "Turns out, it isn't necessarily. Today, deer often have left and right antlers that are different in terms of their branching patterns. Hannah shows dramatically that dinosaurs could be the same way."The differences in the skull's left and right halves are so extreme that had the paleontologists found only isolated halves, they might have concluded that they belong to two different species"The skull shows how much morphological variability there was in the genus," said Holmes. Like the antlers of modern deer and moose, Hannah shows that the pattern of dinosaur horns could vary significantly -- meaning some fossils that were once assumed to be unique species will have to be reevaluated.Tradition dictates that the person who finds an important dinosaur specimen gets to give it a nickname. "Hannah the dinosaur is named after my dog," explained Persons, now a professor and museum curator at the College of Charleston. "She's a good dog, and I knew she was home missing me while I was away on the expedition."Despite the nickname, paleontologists have no way of knowing if the dinosaur was female. But they have learned other details from the skull -- from a partnership with researchers in the Faculty of Engineering."Ahmed Qureshi and graduate student Baltej Rupal in the Faculty of Engineering assisted us in performing a 3D laser scan of the skull," said Persons. "That let our publication to include a digital reconstruction, allowing scientists all over the world to download the 3D model and inspect it in detail.""This is the future of paleontological collections: digital dinosaurs."
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New Species
| 2,019 |
November 25, 2019
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https://www.sciencedaily.com/releases/2019/11/191125121002.htm
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Climate change is reshaping communities of ocean organisms
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Climate change is reshaping communities of fish and other sea life, according to a pioneering study on how ocean warming is affecting the mix of species.
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The study, published in the journal "The changes we're observing ripple throughout local and global economies all the way to our dinner plates," said co-author Malin Pinsky, an associate professor in the Department of Ecology, Evolution, and Natural Resources in the School of Environmental and Biological Sciences at Rutgers University-New Brunswick."We found dramatic evidence that changing temperatures are already reshaping communities of ocean organisms," Pinsky said. "We found that warm-water species are rapidly increasing and cold-water marine species are decreasing as the global temperature rises. Changes like this are often disrupting our fisheries and ocean food chains."An international team of scientists also found evidence that species in some places can avoid declines by seeking refuge in cooler, deeper water -- like plants on land that move to higher elevations to avoid heat, Pinsky said.The scientists compiled the most comprehensive assessment of how ocean warming is affecting the mix of species in our oceans. They looked at fishes, invertebrates such as crabs and other crustaceans and plankton in the North Atlantic and North Pacific, across two continents and two oceans. They analyzed three million records of thousands of species from 200 ecological communities across the globe from 1985 to 2014.Regions with stable temperatures (the Northeast Pacific and Gulf of Mexico, for example) show little change in species dominance, while warming areas (the North Atlantic, for example) are experiencing strong shifts toward the dominance of warm-water species, the study says.Temperature is a fundamental driver for change in marine systems, with restructuring of communities in the most rapidly warming areas. Still, the data "suggest a strong prognosis of resilience to climate change for these communities," the study says."We're now trying to understand how the changes we see in the ocean compare with those on land and in freshwater ecosystems," said Pinsky, who is also a sabbatical professor at the German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig.Scientists at many institutions, led by the Scottish Association for Marine Science, contributed to the study.
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New Species
| 2,019 |
November 25, 2019
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https://www.sciencedaily.com/releases/2019/11/191125120943.htm
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Study tracks genomic changes that reinforce darter speciation
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When they share habitat, orangethroat and rainbow darters tend to avoid one another, even though they are closely related and can produce "hybrid" offspring. The males compete with males of their own species and will almost always ignore females of the other species. A new study offers an analysis of the genomic changes that occur when these fish hybridize, offering insight into the gradual accumulation of incompatible traits that likely drives them to diverge.
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The researchers report their findings in the journal Scientists have spent decades trying to understand the factors that allow closely related organisms to evolve into separate species, said Becky Fuller, a University of Illinois professor of evolution, ecology and behavior who led the research with study lead author Rachel Moran. Now a postdoctoral researcher at the University of Minnesota, Moran conducted the research as a graduate student in Fuller's lab.The most obvious driver of speciation is geographic isolation, but other factors also contribute, Fuller said."For example, two populations may randomly develop anatomical or physiological differences that prevent them from successfully mating with one another," she said.Other behavioral and genomic changes that contribute to species divergence are subtler and more difficult to track, Moran said."We were particularly interested in comparing the orangethroat darter with the rainbow darter because the two species co-occur and can form hybrids," she said. "Interspecies mating is costly for these fish, as it does not result in healthy offspring."If the offspring die, they fail to pass their genetic heritage to the next generation. Those lineages with a proclivity for interspecies mating gradually die out."Consequently, when the two species co-occur in the same habitat, they evolve strong preferences to mate with their own species and ignore the other species," Moran said.To understand how genomic factors influence this process, the researchers mated orangethroat and rainbow darters in the lab and analyzed the genomes of the few hybrid offspring that survived past hatching. They sequenced the genome of the orangethroat darter and conducted a series of analyses to determine which regions of the two species were misaligned."We found that areas of the genome that had a lot of genetic divergence between the two species likely contributed to their reproductive incompatibility," Moran said. These differences are widespread and include problematic variations in the sequence and order of genes on the chromosomes.The differences would likely disrupt cell division and could alter gene expression in hybrid offspring, Fuller said."This study opens a window on the post-reproductive mechanisms that contribute to the evolution of differing traits in closely related species," Fuller said."How species that exchange genetic material through hybridization are able to coexist and remain distinct from one another has puzzled evolutionary biologists for decades," Moran said. "The insights we've gained from this study have hopefully gotten us a little closer to answering that big question."
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New Species
| 2,019 |
November 21, 2019
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https://www.sciencedaily.com/releases/2019/11/191121121742.htm
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Mathematician develops model to control spread of aquatic invasive species
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Adjusting the water flow rate in a river can prevent invasive species from moving upstream and expanding their range. An applied mathematician at UT has developed a partial differential equation model to find the desired flow rate to reduce invasive populations.
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The model is detailed in a new paper by Suzanne Lenhart, Chancellor's Professor and James R. Cox Professor of Mathematics, published in "Invasives pose a serious threat to native habitats and species, especially in aquatic environments," said Lenhart. "Using optimal control techniques in a model with realistic hydrology features, we illustrated how to adjust the flow rate in a river to keep an invasive species from moving upstream."Mathematical models like the PDE model in this study, which represents an invasive population in a river, can give insight into new management strategies. Current strategies to prevent upstream expansion of invasive species include electric fences or nets in the river, but these are not the only management actions that can be taken.River flow affects species survival success in habitats. Lower flow rates increase the chance of a species persisting, and higher flow rates inhibit success by limiting the species's range and chance of survival. This study investigates how water discharge rates, controlled by water release mechanisms like dams, can force the invasive populations downstream while minimizing the cost of management."With our model, we show how far the invasive population moves upstream with no control, constant control, and optimal control of water discharge," said Lenhart. "As expected, the populations with no control are able to move further upstream, and we can manipulate the control levels to find the desired flow rate.""In the future, we hope to apply these results with new data to a particular invasive species like Asian carp," said Lenhart.
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New Species
| 2,019 |
November 20, 2019
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https://www.sciencedaily.com/releases/2019/11/191120121130.htm
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A decade after the predators have gone, Galapagos Island finches are still being spooked
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On some of the Galapagos Islands where human-introduced predators of Darwin's finches were eradicated over a decade ago, the finches are still acting as though they are in danger, according to research published today in the
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The study found that the finches' fearful responses -- known as antipredator behaviour -- were sustained through multiple generations after the threat was gone, which could have detrimental consequences for their survival.The work by Dr Kiyoko Gotanda, a zoologist at the University of Cambridge, is one of the first studies to look at behavioural adaptations in a species following the eradication of invasive predators. The research focused on one species of Darwin's iconic finches -- the small ground finch, "These surprising results suggest that whatever influences this fearful behaviour is more complicated than just the presence or absence of invasive predators," said Gotanda, sole author of the paper.The Galapagos Islands provide a natural stage to compare different predator situations. Some islands have never had invasive predators, others currently have predators like domestic cats and rats that arrived with humans, while others have had these predators in the past and they have now been eradicated.Gotanda found that finches on islands with predators were wary, and flew away from an approaching researcher -- imitating an approaching predator -- at a much greater distance than the finches on pristine islands without predators. This increased antipredator behaviour has been maintained on islands where invasive predators have been successfully eradicated, even though eradication happened eight and thirteen years earlier."While the mechanism for the transmission of the fearful behaviour through the generations requires further study, this sustained response has consequences for evaluating conservation efforts," said Gotanda. "The time and energy finches spend spooking themselves by fleeing when they are not in danger could be better spent looking for food, mating, laying eggs, and rearing their young."Conservation management of species of concern on islands often involves getting rid of invasive predators. Understanding how species adapt their behaviour once predators have been eradicated -- and how quickly this occurs -- could better inform efforts to support the recovery of a target species. Understanding the effects of human influence such as the introduction of invasive predators could help predict how species respond to rapidly changing environments.Gotanda also looked at the effect of urbanisation on finch behaviour and found -- as is generally seen in towns and cities -- the birds were less fearful as they became used to the presence of humans. On some islands the urban finches were even bolder than those on islands that had never seen invasive predators at all. This could make them vulnerable to threats like invasive predators, which are present in urban areas on the Galapagos. This suggests that the effects of urbanisation on species are strong enough to counteract adaptations to other human influences such as invasive predators.When Charles Darwin visited the Galapagos Islands during his Voyage of the Beagle in 1835, he could famously get close enough to throw his hat over the birds. The animals were so unused to humans that they did not see Darwin -- a potential predator -- as a threat. Since then, the arrival of both humans and invasive predators such as cats and rats on many of the islands drove the birds to develop fear, and fly away at the sight of danger. Subsequent eradication efforts have been necessary to protect the iconic finches.
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New Species
| 2,019 |
November 19, 2019
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https://www.sciencedaily.com/releases/2019/11/191119105539.htm
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New species of seaweed uncovered by genetic analyses
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Genetic analyses have revealed remarkably higher species diversity in common red seaweed than previously assumed. It was thought that there were only five related species of the
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These discoveries were made by an international research collaboration group consisting of the following members from Kobe University; Assistant Professor Takeaki Hanyuda, Professor Hiroshi Kawai (both of the Research Center for Inland Seas) and Kensho Yamamura (2nd year Masters in Biology at the Graduate School of Science).The results of this research were published in the following journals; 'Until recently, there were five identified species worldwide, three of which were found in Japan- 'fukuro-funori' (Genetic analysis also suggested that some populations of The research group also genetically analyzed the type specimen of To discover more about the The results confirmed that there is a separate species that was previously thought to be the same as This research also revealed that a species previously found in Korea --
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New Species
| 2,019 |
November 19, 2019
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https://www.sciencedaily.com/releases/2019/11/191119105442.htm
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Striking variation in mechanisms that drive sex selection in frogs
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Researchers from McMaster University have discovered striking variation in the underlying genetic machinery that orchestrates sexual differentiation in frogs, demonstrating that evolution of this crucial biological system has moved at a dramatic pace.
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A team of biologists examined more than two dozen species of Pipidae, a family of frog found in tropical South America and sub-Saharan Africa, which includes African clawed frogs, a smooth-skinned frog with webbed feet and claws on the hind legs.They used modern techniques to study a gene known to trigger female development, dm-w, in over 20 species, each of which have both males and females, and requires sexual reproduction to breed.Researchers discovered that the genes governing sexual selection differed radically across species."Sexual differentiation is fundamentally important in an evolutionary context," says Ben Evans, lead author of the study and a professor of biology at McMaster University."Once you have a system that works so well, one might expect that natural selection would guard against changes to that system. This is why it's so surprising that the genetic basis for sexual differentiation in fact evolved extremely rapidly in pipid frogs," he says.The team found at least seven different systems in place for regulating sex determination across closely related species. Evans explains that three underlying mechanisms within the developmental systems are at work.In some species, female frogs lost dm-w and use another, unknown gene to determine sex, suggesting dm-w stopped functioning over time. In other frog families, scientists were surprised to find the gene was present in both sexes, suggesting the function of gene became sidelined. In yet other species, dm-w became empowered into a potent female-specific sex determining gene."The results of this study," says Evans. "reminds us that evolution happens no matter how important a certain mechanism or trait might be."The study was published in the journal
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New Species
| 2,019 |
November 18, 2019
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https://www.sciencedaily.com/releases/2019/11/191118110922.htm
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Unlikely wasp enemy of a serious alien pest in North America named Idris elba
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A parasitic wasp was recently discovered in Guanajuato, Mexico, where it was found to parasitize the eggs of an invasive stink bug, known as the bagrada bug, which is a major pest of cruciferous vegetables. A research team from Colegio de Postgraduados (Mexico), Agriculture and Agri-Food Canada (AAFC) and the Florida State Collection of Arthropods (FSCA) collaborated to publish a study on the biology this species,
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The genus The discovery of this wasp marks an important step toward the development of efficient and natural control of the stink bug species Bagrada hilaris in North America. Commonly known as the bagrada bug, it is native to Africa, but is already an established and important pest of over 74 plant species in India, southern Europe, southern Asia and the Middle East. Across the Atlantic, it has been known since 2008, when it was reported from Los Angeles, California (USA), followed by records from Coahuila state, Mexico, in 2014. Three years later, it was also found in the state of Guanajuato, which is responsible for over 70% of the country's broccoli production, as well as the major import of broccoli and cauliflower in the USA and Canada. So far, measures to halt the bug's invasion have proven largely ineffective, and its distribution is expected to reach new ecosystems of economical importance.While not unheard of, it is uncommon for native parasitoids to attack an introduced host. It is no coincidence that this wasp has the species name "elba." Dr. Talamas explained that explicitly naming the species after Idris Elba (the actor), also known as a patronym, would have to follow Latin grammar and become Four-time Golden Globe nominee for Best Actor, Idris Elba is a famous British actor, producer, writer, singer, DJ and producer, best known for a long list of blockbusters, including a good number of superhero movies, such as the Marvel series inspired by the myths of the Norse god Thor. There, Elba stars as Heimdall, whose almost namesake: Heimdallr, is a Norse deity believed to be the sole protector of the bridge linking the human world and the realm of the gods.
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New Species
| 2,019 |
November 13, 2019
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https://www.sciencedaily.com/releases/2019/11/191113075101.htm
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Ant expert discovers newly emergent species in his backyard
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Jack Longino is a global ant expert and has traveled the world documenting and discovering ant species. But for his latest discovery, he didn't need to go any farther than his own backyard. In August 2018, just after dark, Longino caught a glimpse of four ants in his garden that really looked out of place. The next day he dug deeper and found more specimens. They reminded him of species he knew from the tropics or from the deciduous forests of the eastern U.S.
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But the surprises didn't stop there. Longino originally thought the ants had been introduced to the area, possibly through the commercial potting soil, and would be some known species from elsewhere. But a close look in the lab revealed that it was a distinct new species, almost certainly native to the region, with similarities to related species in Arizona. Longino surmised that the ant, which likes warm, moist habitats, has been living underground in Utah's typically dry climate. More than 150 years of irrigation and introduced forest, however, may have given the ant courage to once again come to the surface. For that reason, he named the new ant New and important discoveries could be waiting close to home, Longino writes with colleague Douglas Booher in a paper published in
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New Species
| 2,019 |
November 12, 2019
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https://www.sciencedaily.com/releases/2019/11/191112140902.htm
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Songbirds sing species-specific songs
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The generation of species-specific singing in songbirds is associated with species-specific patterns of gene activity in brain regions called song nuclei, according to a study published November 12 in the open-access journal
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Learning of most complex motor skills, such as birdsong and human speech, is constrained in a manner that is characteristic of each species, but the mechanisms underlying species-specific learned behaviors remain poorly understood. Songbirds acquire species-specific songs through learning, which is also thought to depend on species-specific patterns of gene activity in song nuclei -- brain regions known to be specialized for vocal learning and production.In the new study, Wada and colleagues made use of two closely related songbird species -- the zebra finch (The researchers compared the songs of birds that had been taught the same species' song versus those that had only heard the other species' song; this showed that the song learning was mostly regulated by species-specific genetic differences. They then identified genes whose activity in song nuclei is regulated in a species-specific fashion, either by changes in the genes' own regulatory regions ("cis-regulation") or by changes in other proteins that affect a gene's activity ("trans-regulation").They found that trans-regulatory changes were more prevalent than cis-regulatory changes and tended to primarily affect the activity of genes involved in the formation of nerve connections and transmission of information between neurons in one particular song nucleus, "RA" -- considered as birds' counterpart to the mammalian laryngeal motor cortex.They identified a signaling molecule called BDNF as a mediator of changes in trans-regulated of genes in RA, with a significant correlation between individual variation in the amount of BDNF and species-specific song properties. This was supported by the fact that the use of a drug to over-activate BDNF receptors altered the activity of trans-regulated genes in the RA and disrupted the structures of learned songs in the adult zebra finch.These results demonstrate functional neurogenetic associations between inter-species differences in gene regulation and species-specific learned behaviors. According to the authors, future research building on these findings could reveal the specific gene regulatory changes that underlie the evolution of species-specific learned behaviors."We believe that this isn't just about bird songs," the lead author, Kazuhiro Wada said. "Our study is a promising step to understand how the changes in gene regulation could eventually lead to the evolution of species-specific animal behaviors."
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New Species
| 2,019 |
November 12, 2019
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https://www.sciencedaily.com/releases/2019/11/191112130405.htm
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Bats don't rely on gut bacteria the way humans do
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Just about all mammals, including humans, rely on a community of helpful bacteria living in our guts to help us digest food and fight off diseases. We've evolved along with these bacteria, to the point that closely related species have similar microbiomes in their guts. Scientists just discovered that bats break that rule. That tells us that bats probably don't rely on their microbiomes the way other mammals do -- we think it's because they fly.
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Right now, there are trillions of bacteria living in your gut, making up about one percent of your body weight. They're supposed to be there -- we need them to help us digest food and fight off diseases. The same is true for most mammals; in general, just about every mammal from dogs to dolphins relies on a community of helpful bacteria, called a microbiome, living inside them for health and survival. Many animals have even evolved along with their gut bacteria to better work together, to the point that closely related host species typically share more similar microbiomes. But a new study has identified one group of mammals that seems to buck that trend: bats. A new paper in "It shifts the paradigm we've been operating under, that animals require microbes for digestion and nutrient acquisition. That's true for us, but it may not be true for all species," says lead author Holly Lutz, a research associate at Chicago's Field Museum and post-doctoral researcher at the University of California, San Diego. "The trends we're seeing suggest that bats may not depend on bacteria the same way many other mammals do, and that they can survive just fine without a strict suite of bacteria in their guts to help them digest their food."To learn about the relationships between bats and their microbes, Lutz and her colleagues took samples of bacteria from the skin, tongues, and guts of 497 bats from 31 different species in Kenya and Uganda. The team then compared the genetic codes present in the bacteria.The researchers discovered that bats have fewer bacterial species living in their guts than in their mouths and on their skin. What's more, the kinds of bacteria living in the bats' guts varied from species to species without following any apparent evolutionary pattern. This struck the scientists as strange, since for most other mammals that have been studied, closely-related hosts share more similar microbiomes, a pattern called "phylosymbiosis." Bats seem to play by a different set of rules."There's essentially no relationship between the bat microbiome and bat evolutionary history," says Lutz. "You'd expect to see similar microbiomes in closely-related bat species if these animals depended strongly on their bacteria for survival. This is largely what we've seen in other mammals that have been studied, but it's just not there in bats." While host identity-what species a bat is- is still an important factor in predicting the microbiome, this may simply be tied to where those bats live and what they eat. In other words, the bat microbiome may be the result of bacteria that the bats pick up from their environment rather than from an evolutionary predisposition to hosting specific bacteria. "The same species of bat in five locations might host five very different microbial communities," says Lutz. The fact that bats' gut bacteria are more closely tied to where bats live than where those bats fall on the bat family tree indicates that evolving a special relationship with just-right gut bacteria may not have been as important for bats as it has been for other mammals.Lutz suspects that bats' unique relationships with gut bacteria are related to another trait that sets them apart from their fellow mammals: their ability to fly."Bats have extremely shortened guts," she explains. Food takes just fifteen to thirty minutes to pass through a bat's digestive system, a third as long as it would take for a similarly-sized rodent. That's likely because a long, winding digestive tract would weigh the bats down. "For bats, you can't be carrying around non-essentials. You need to reduce weight for flying -- you don't want a heavy gut." Since bats evolved short digestive tracts, presumably to make them lighter for flight, they may not have evolved the same intimate relationships with their gut bacteria that us land-dwelling mammals have.The discovery that bats' microbiomes are closely linked to the world around them means that changes to that world could put the bats in danger. In addition to helping digest food, stable gut bacteria help maintain healthy immune systems to fight off disease, and scientists are still learning about the relationship between microbes and skin, gut, and oral health in wildlife. "Bats may be very susceptible to environmental change -- if they have a transient microbiome, they might not have the most stable defense mechanisms," says Lutz. "Human-caused disturbances to the environment are a very important issue. Bats may be extra-fragile and more at risk."In addition to lead author Holly Lutz of the Field Museum, University of Chicago, and UC San Diego, the study was contributed to by senior author Jack Gilbert at UC San Diego, Field Museum co-authors Julian Kerbis Peterhans, Terry Demos, and Bruce Patterson, Elliott Jackson of Cornell University, Paul Webala of Maasai Mara University in Kenya, and Waswa Babyesiza of the Sokoine University of Agriculture in Tanzania.
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New Species
| 2,019 |
November 12, 2019
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https://www.sciencedaily.com/releases/2019/11/191112081613.htm
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Larger than life: Augmented ants
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An ant the size of a lion isn't as far-fetched as you would think. From as small as a sesame seed to the size of a big cat, ants come in all sizes -- in augmented reality, at least.
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Augmented reality provides an interactive experience of the 'real world' with the help of computer-generated images viewed through a screen. It's a technology often used in videogames to meld computer-generated images with reality. Now researchers in the Biodiversity and Biocomplexity Unit at the Okinawa Institute of Science and Technology Graduate University (OIST) have used this high tech approach to create the first ever augmented reality experience that pairs with a taxonomic research paper. The research, published in Insect Systematics and Diversity, presents six new species of Strumigenys ants, also known as miniature trap-jaw ants, from Fiji."In our lab we have been working on tools to interact with biodiversity data in different ways," said Prof. Evan Economo, senior author of the study. "The specimens we study are locked away in natural history museums, and not easily accessible to both researchers and the general public."The ant specimens are now accessible anywhere and everywhere with the interactive taxonomic app, Insects3D. The scientists used 3D x-ray scans to create digital models of the ants. Insects3D allows a user to view 3D models of ant specimens in augmented reality and lets them place ants in the real world using the app. Users can even magnify the species to the size of a lion if they please."When we made the app I gave it to my five-year old son," Economo said. "He spent an hour running around the house putting ants everywhere."It's not just Economo's son -- augmented reality allows new scientific experiences for a broad range of people. This app allows those from all corners of the world to engage with the same data. All you need is an iPhone. Economo believes this technology will ignite a new way of experiencing research."With this app, we hope to get more people interested and help everyone see what the potential could be in the future," Economo said. "We have six [ant] models and geographic maps of where they are found. It's just the beginning and we are excited by what's to come."The new biodiversity data on the ants are a detailed description of the anatomy of each species, including their unusual trap-like mandibles. The ant is in a global group that appears to have undergone adaptive radiation in Fiji. This radiation occurs when one evolutionary lineage splits into multiple species, thus diversifying. Economo and first author on the paper, Eli Sarnat, started their fieldwork in 2004. 23 species from their collecting are presented in the paper and six represent new species discovered for the first time. Economo and Sarnat didn't expect one-third of the species they collected to be new to science since Fiji is a small remote archipelago."The main research of the lab is understanding the evolution of insect diversity around the world, and new species discovery is a part of that," Economo said. "Rather than just describing new species in papers very few will read, we are interested to push the boundaries of technology and how we share results with our colleagues and the public."Pushing boundaries is nothing new in science. This technology extends beyond taxonomic research use -- researchers in other disciplines can use this approach to explore new ways to display their scientific discoveries.
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New Species
| 2,019 |
November 11, 2019
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https://www.sciencedaily.com/releases/2019/11/191111154150.htm
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New fossil pushes back physical evidence of insect pollination to 99 million years ago
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A new study co-led by researchers in the U.S. and China has pushed back the first-known physical evidence of insect flower pollination to 99 million years ago, during the mid-Cretaceous period.
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The revelation is based upon a tumbling flower beetle with pollen on its legs discovered preserved in amber deep inside a mine in northern Myanmar. The fossil comes from the same amber deposit as the first ammonite discovered in amber, which was reported by the same research group earlier this year.The report of the new fossil will publish Nov. 11 in the journal of the The study's U.S. co-author is David Dilcher, an emeritus professor in the IU Bloomington College of Arts and Sciences' Department of Earth and Atmospheric Science and a research affiliate of the Indiana Geological and Water Survey. As a paleobotanist studying the earliest flowering plants on Earth, Dilcher has conducted research on the process of amber fossilization.The co-lead author on the study is Bo Wang, an amber fossil expert at the Nanjing Institute of Geology and Palaeontology, where the specimen was procured and analyzed.According to Dilcher, who provided a morphological review of the 62 grains of pollen in the amber, the shape and structure of the pollen shows it evolved to spread through contact with insects. These features include the pollen's size, "ornamentation" and clumping ability.The grains also likely originated from a flower species in the group eudicots, one of the most common types of flowering plant species, he said.The pollen was not easy to find. The powdery substance was revealed hidden in the insect's body hairs under a confocal laser microscopy. The analysis took advantage of the fact that pollen grains glow under fluorescence light, contrasting strongly with the darkness of the insect's shell.The insect in the amber is a newly discovered species of beetle, which the study's authors named Angimordella burmitina. It's role as a pollinator was determined based upon several specialized physical structures, including body shape and pollen-feeding mouthparts. These structures were revealed through an imaging method called X-ray microcomputed tomography, or micro-CT."It's exceedingly rare to find a specimen where both the insect and the pollen are preserved in a single fossil," said Dilcher. "Aside from the significance as earliest known direct evidence of insect pollination of flowering plants, this specimen perfectly illustrates the cooperative evolution of plants and animals during this time period, during which a true exposition of flowering plants occurred."Prior to this study, the earliest physical evidence of insect pollination of flowering plants came from Middle Eocene. The age of the new fossil was determined based upon the age of other known fossils in the same location as the fossilized beetle's discovery.
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New Species
| 2,019 |
November 11, 2019
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https://www.sciencedaily.com/releases/2019/11/191111124755.htm
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Evolutionary diversity is associated with Amazon forest productivity
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An international team of researchers led by the University of Leeds have revealed for the first time that Amazon forests with the greatest evolutionary diversity are the most productive.
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The team used long term-records from 90 plots as part of the Amazon Forest Inventory Network (RAINFOR) and ForestPlots.net to track the lives and productivity of individual trees across the Amazon region. By combining these records with DNA sequence data -- which identified the evolutionary relationships among all the species -- the team was able to investigate the links between how fast different forests grow and their diversity.Their study demonstrated that the plots with the greatest evolutionary diversity were a third more productive compared to areas with the least evolutionary diversity.The finding suggest that evolutionary diversity should be an important consideration when identifying priority areas for conservation.Study lead author Fernanda Coelho from the School of Geography at Leeds said: "Understanding how biodiversity affects productivity in tropical forests is important because it allows us to understand how conservation strategies can best be designed to maximise protection of species and the services that these ecosystems provide."Our results indicate that we should include evolutionary history in conservation priorities -- because ecosystem function may be higher in areas where species come from right across the tree of life'.
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New Species
| 2,019 |
November 8, 2019
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https://www.sciencedaily.com/releases/2019/11/191108171641.htm
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Fossil suggests apes, old world monkeys moved in opposite directions from shared ancestor
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In terms of their body plan, Old World monkeys -- a group that includes primates like baboons and macaques -- are generally considered more similar to ancestral species than apes are. But a new study that analyzes the first well-preserved femur of
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"Our study shows that The fossil analyzed in the study was discovered in 2009 and is the most complete femur of For the analysis, the authors compared the fossil bone to other extinct and modern species, including humans, chimpanzees, and Victoriapithecus and Homunculus (extinct Old World and New World monkeys, respectively). The evolutionary modeling analysis used in the study included a method that was developed to identify convergent evolution in anole lizards in the Caribbean, which have independently developed comparable niche-specific adaptations across various islands.The results indicate that the ancestral hip joint is, from an evolutionary perspective, as far from the hip joint of modern Old World monkeys as from those of the great apes -- suggesting that each group evolved a distinct way of moving as they specialized for success in different environmental niches.In addition, evolutionary modeling suggests that living great apes -- including orangutans, chimpanzees, and gorillas -- may have independently developed similar hip joint anatomy that allows wide-ranging, flexible movement through their arboreal habitats."What I find really exciting about the modeling approach is that we can develop better hypotheses about what drove the divergence of apes and monkeys, and the emerging picture is that navigating the environment is one of the key factors," said Ashley Hammond, assistant curator in the Division of Anthropology and an author on the study.
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New Species
| 2,019 |
November 5, 2019
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https://www.sciencedaily.com/releases/2019/11/191105104439.htm
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Infectious cancer in mussels spread across the Atlantic
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An infectious cancer that originated in one species of mussel growing in the Northern Hemisphere has spread to related mussels in South America and Europe, says a new study published today in
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The findings also suggest that humans may unwittingly be contributing to the worldwide spread of infectious cancers that can affect mussels and other bivalves such as clams and cockles.Most cancers arise when DNA mutations occur in an organism's cells that cause uncontrolled cell growth. While these cancerous cells do not normally spread to others, there are a few exceptions."Tasmanian devils, dogs and bivalves have all developed cancers that can spread to others, acting more like a pathogen or parasite," explains lead author Marisa Yonemitsu, Research Technician at the Pacific Northwest Research Institute in Seattle, Washington, US. One such cancer, called a bivalve transmissible neoplasia, was previously found in a species of mussel called In the current study, Yonemitsu and her colleagues sequenced DNA from cancer cells in the related species M. edulis, from France and the Netherlands, and M. chilensis, which lives on the coasts of Chile and Argentina. They wanted to determine whether the cancers are transmissible neoplasias and, if so, whether they were from the same lineage as the one in Unexpectedly, the team discovered that cancer cells collected in mussels from Europe and South America were nearly identical genetically, suggesting they came from a common origin -- likely a single "Since Mytilus mussels do not live in the equatorial zone, it would have been nearly impossible for them to have spread this cancer between South America and the Northern Hemisphere on their own," notes senior author Michael Metzger, Assistant Investigator at the Pacific Northwest Research Institute. Instead, he says it is likely they were transported accidentally on international shipping vessels."Our study shows that infectious cancers in bivalves are widespread pathogens and that human intervention may be responsible for introducing them into new susceptible populations and species," Metzger concludes. "Further studies will allow us to learn more about how these cancers evolve when introduced into new host species and how the hosts themselves can evolve in response."
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New Species
| 2,019 |
November 1, 2019
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https://www.sciencedaily.com/releases/2019/11/191101111603.htm
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Gene flow among distantly-related butterfly species
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An international team of researchers analyzed the genomes of 20 butterfly species and discovered a surprisingly high amount of gene flow among them -- even between species that are distantly related. The findings, published in the journal
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Different species of passion vine butterflies (To understand how butterflies pass genes to other species by hybridizing, a process known as introgression, the researchers analyzed new genome assemblies of 20 "DNA sharing had been shown in closely related species, but we wanted to probe deeper into the phylogenetic tree," said senior author James Mallet, Professor of Organismic and Evolutionary Biology in Residence and Associate of Population Genetics in the Museum of Comparative Zoology. "What we found is really astonishing: introgression even among species that are distantly related. "Species" are simply not what we thought they were, and now we have the data to show it. The evolutionary tree of butterflies is a complete morass of inter-connectedness -- every bit of the butterfly genome seems to have a different tree."Lead author Nate Edelman, a graduate student in the Mallet group, explained that the new genome assemblies function as detailed genomic maps. They are constructed by sequencing short fragments of DNA, then assembling them in the proper order. Genome assemblies are an important resource for researchers, as they make it possible to map genes back to the genome."The cool thing about making genome assemblies instead of simple genome "resequencing" is that it's not just the DNA bases that change -- the entire structures of genomes can change through evolutionary time," Edelman said. "And using the assemblies, we can detect those changes."When they began analyzing the assemblies, the team found evidence that some genes were capable of moving between species, and others were far more resistant to the process. One of the key factors that determining whether a gene could or could not move is a basic biological process called "recombination.""In humans and most animals, every individual inherits two copies of their genome, one from her mother, and one from her father," explained Mallet. "The reason you differ genetically from your sibling is due to recombination. Your father contributed to you a newly scrambled, recombined copy of his own parents' genomes, as did your mother with her parents' genomes. So the combination of components from each parent is different in every individual."Recombination is thought to be advantageous if the goal is to generate diverse genotypes for future generations. The system of recombination described in this study suggests that it also occurs during gene flow between species. According to the authors, this could provide a possible route for adaptive genes to be passed occasionally between species, as well within species."It might seem that useful genes are more likely to be transferred between species," said co-author Michael Miyagi of Harvard University. "That's true, but there are also more mundane structural issues with the genome that mean some regions are more likely to have genes go back and forth."According to Edelman, whether those genes flow back and forth often depends on how much those different regions recombine."In low recombination regions, we tend to see more resistance to gene flow than in high recombination regions," he said. "What we think happens is that in very high recombination regions, the genes that are resistant or incompatible become dissociated from the genes that can flow across the species boundary."The team was able to identify a key gene that acts to switch color patterns as one that moved between species."The new genome assemblies also led to the discovery of a new, larger inversion on a different chromosome.Using the new analysis method developed by Miyagi, the researchers showed that one of those inverted sequences was transferred among species."If we look at any specific chunk of DNA, each one has a specific history," Miyagi explained. "So the method we developed looks at these bits of DNA and can tell us which ones are more or less likely to be introgressed."The study concludes that hybridization is one way for species to derive their genomes, and may be a key process in the creation of the diversity of life we see today."In nature, it's very unlikely that any individual will mate with a member of another species," Mallet said. "But over evolutionary time, it does happen. It probably only happens in the 'youngest' groups of species -- species that are rapidly evolving. Most of the diversity of life is probably created in these rapid radiations. They are involved in events such as the origin of mammals. During these radiations, the hybridization and introgression we document here could be an important means of shuffling variation and recombining adaptations from different lineages."The study has its roots in the "Open data and sharing between laboratories is so important for understanding evolution, and how bursts of diversity happen," said Mallet. "In this international consortium we've each brought very different strengths and helped each other do much better science overall, and the result has been a resource that our collaborators, as well as anyone else, can use well into the future."
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New Species
| 2,019 |
October 30, 2019
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https://www.sciencedaily.com/releases/2019/10/191030151418.htm
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Alongside Ötzi the Iceman: A bounty of ancient mosses and liverworts
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Buried alongside the famous Ötzi the Iceman are at least 75 species of bryophytes -- mosses and liverworts -- which hold clues to Ötzi's surroundings, according to a study released October 30, 2019 in the open-access journal
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Ötzi the Iceman is a remarkable 5,300-year-old human specimen found frozen in ice approximately 3,200 meters above sea level in the Italian Alps. He was frozen alongside his clothing and gear as well as an abundant assemblage of plants and fungi. In this study, Dickson and colleagues aimed to identify the mosses and liverworts preserved alongside the Iceman.Today, 23 bryophyte species live the area near where Ötzi was found, but inside the ice the researchers identified thousands of preserved bryophyte fragments representing at least 75 species. It is the only site of such high altitude with bryophytes preserved over thousands of years. Notably, the assemblage includes a variety of mosses ranging from low-elevation to high-elevation species, as well as 10 species of liverworts, which are very rarely preserved in archaeological sites. Only 30% of the identified bryophytes appear to have been local species, with the rest having been transported to the spot in Ötzi's gut or clothing or by large mammalian herbivores whose droppings ended up frozen alongside the Iceman.From these remains, the researchers infer that the bryophyte community in the Alps around 5,000 years ago was generally similar to that of today. Furthermore, the non-local species help to confirm the path Ötzi took to his final resting place. Several of the identified moss species thrive today in the lower Schnalstal valley, suggesting that Ötzi traveled along the valley during his ascent. This conclusion is corroborated by previous pollen research, which also pinpointed Schnalstal as the Iceman's likely route of ascent.Dickson adds, "Most members of the public are unlikely to be knowledgeable about bryophytes (mosses and liverworts). However, no fewer than 75 species of these important investigative clues were found when the Iceman (aka Ötzi) was removed from the ice. They were recovered as mostly small scraps from the ice around him, from his clothes and gear, and even from his alimentary tract. Those findings prompted the questions: Where did the fragments come from? How precisely did they get there? How do they help our understanding of the Iceman?"
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New Species
| 2,019 |
October 23, 2019
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https://www.sciencedaily.com/releases/2019/10/191023172116.htm
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By cutting out one gene, researchers remove a tadpole's ability to regenerate
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Tadpoles of frogs that can typically regrow amputated tails or limbs lost their ability to regenerate after researchers blocked the expression of a newly identified gene that is one of the drivers for this regrowth. Furthermore, scientists hypothesize that the loss of appendage regeneration in warm-blooded animals might have been caused by the gain or loss of this gene, dubbed c-Answer, in an ancestor's genome during evolution. The work appears October 22 in the journal
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"We suppose that genes can only disappear if removing them has advantages for the animal," says first author Daria Korotkova of the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry in Moscow. "So, we suggest that when this gene disappeared from warm-blooded species it was by a mutation, acting as a trade-off for the loss of appendage regeneration."Using a computer algorithm, the researchers identified several genes that disappeared in the genomes of warm-blooded vertebrates, including humans, but are present in cold-blooded ones. They did this by searching the DNA of African clawed frogs, The research team, including Korotkova, Andrey Zaraisky, Vassily Lyubetsky, Anastasiya Ivanova, Lev Rubanov, Alexander Seliverstov, Oleg Zverkov, Natalia Martynova, Alexey Nesterenko, Maria Tereshina, and Leonid Peshkin, then overexpressed or blocked c-Answer in tadpole embryos. They discovered that enhancing c-Answer allowed tadpoles to regenerate lost tails earlier in their life than those that hatched naturally, whereas tadpoles with c-Answer blocked could transition into frogs but could not regenerate amputated appendages."C-Answer modulates at least two important molecular pathways that are common to all vertebrates," says senior author Zaraisky, head of the laboratory of molecular bases of embryogenesis at the Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry. "Its loss in evolution might alter the functioning of these pathways and, accordingly, lead to major physiological transformations.""We also found that over expression of c-Answer causes advanced brain growth and larger eyes, which surprised us, since it means c-Answer modulates for regeneration and brain development," says Korotkova. "However, it was observed that when c-Answer is blocked, This work was supported by This work was supported by the Russian Foundation for Basic Research and the National Institutes of Health.
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New Species
| 2,019 |
October 22, 2019
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https://www.sciencedaily.com/releases/2019/10/191022152740.htm
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Ways to reduce errors in wildlife surveys
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Research led by a University of Montana undergraduate student to identify less error-prone methods for performing wildlife surveys was published Oct. 20 in
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Biologists around the world use a variety of boots-on-the-ground field methods to survey animal populations. When extrapolated, these data provide population counts and other scientific information used to study and manage species. But counting wildlife is rarely straightforward. Birds, for instance, are small or sometimes hard to see, and many species look and sound similar."Many biologists assume that false positives -- either misidentifications or double-counts of animals -- don't happen in their surveys. But research has shown that false positives happen quite a lot, and those false positives can have huge impacts on the reliability of population estimates that we calculate from those data," said first author Kaitlyn Strickfaden, a researcher with UM's Avian Science Center. "So we made bird call simulations in which we knew the true identity of every calling bird to test differences in false positive rates in a few survey scenarios."Strickfaden and her co-authors tested different experience levels (expert and naive) and two survey methods. The first survey method used a single observer while the second used two collaborating observers.Strickfaden and her team created call simulations featuring mashups of songs from 10 different bird species. The researchers knew when particular species were calling throughout each of the simulations. Their volunteer observers -- six experts and six beginners -- did not. These observers listened to the call simulations, either alone or with another observer, and recorded the birds they thought they heard.The double-observer method reported significantly lower false-positive rates regardless of the observers' experience level.Observer experience was also an important factor, reaffirming that proper training is crucial to minimizing misidentifications during data collection.The researchers found that error rates varied widely by species. Species with more unique songs were not misidentified as often as other species in the study. There also was an uneven trade-off in misidentifications within similar-sounding pairs. For example, McCown's longspurs were often misidentified as horned larks, so horned larks were greatly overcounted in the study compared to how many truly occurred, while McCown's longspurs were greatly undercounted."We don't make any claims about what survey method researchers should use, since every researcher's situation is different, but our data do show that the double-observer method was less prone to errors than the single-observer method," Strickfaden said. "Collecting more accurate data gives us the ability to more accurately estimate population sizes. When we ignore false-positive errors, we may not know when populations are doing poorly and need conservation actions. Our research is a step forward in addressing this problem."Strickfaden, who graduated from UM in 2018 with a wildlife biology degree, has worked in the Avian Science Center since 2017. She conducted this research as her undergraduate senior thesis project."Kaitlyn's persistence and tenacity is admirable. Publishing her undergraduate senior research in
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New Species
| 2,019 |
October 17, 2019
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https://www.sciencedaily.com/releases/2019/10/191017141049.htm
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First scientific description of elusive bird illuminates plight of Borneo's forests
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Scientists with the Smithsonian's National Museum of Natural History and collaborators surveying the birdlife of Borneo have discovered a startling surprise: an undescribed species of bird, which has been named the Spectacled Flowerpecker. While scientists and birdwatchers have previously glimpsed the small, gray bird in lowland forests around the island, the Smithsonian team is the first to capture and study it, resulting in its formal scientific description as a new species.
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The team's study, reported Oct. 17 in the journal "This bird is totally unique," said Christopher Milensky, collections manager for the museum's Division of Birds and the leader of the Smithsonian survey that led to the new discovery. "It's unlike anything else, and it is the latest example of the rich biodiversity that can be found in this region."The tropical island of Borneo in Southeast Asia is home to hundreds of species of birds, including dozens that can be seen nowhere else in the world. But the Spectacled Flowerpecker has drawn special attention since it was first photographed and reported on by a group of birders in 2009. The bird's stout, pot-bellied body and stubby bill immediately suggested it was a flowerpecker, but its distinctive facial markings -- the prominent white arcs above and below the eyes that give the bird its spectacled appearance -- were unfamiliar. That group, which included University of Leeds ornithologist David Edwards, dubbed the bird with a common name -- Spectacled Flowerpecker -- and proposed that it might be a species new to science.For the next 10 years, birds matching the description of the Spectacled Flowerpecker were spotted periodically in lowland forests around the island. But it was not until earlier this year, when Milensky and Jacob Saucier, museum specialist and the team lead on the study formally describing the new species, found the elusive creature in a remote wildlife preserve in Southwestern Borneo, that scientists had an opportunity to study the Spectacled Flowerpecker directly.Milensky and Saucier were collaborating with Malaysia's Sarawak Forestry Corporation to document the diversity of bird species living in the Lanjak Entimau Wildlife Sanctuary. Their research site was miles from any reported Spectacled Flowerpecker sightings, so discovering one was unexpected. Still, Milensky said, he recognized it immediately. "I was fairly certain that's what it was, and I knew it had not been formally described and documented," he said. "As soon as I saw it, I knew we had a new species of bird to describe."Milensky and Saucier returned to the museum to examine the bird closely, analyzing its external features and comparing its DNA to that of other flowerpeckers. Their genetic analysis turned up another surprise when the team realized how distinct the new bird was from its family members. "It isn't related to any of the other flowerpeckers all that closely," Saucier said. "It's a whole new species that distinctly stands out."The Smithsonian team also analyzed the bird's diet. Like other flowerpeckers, the new species has been spotted eating mistletoe, a parasitic plant that grows high in the forest canopy. Through DNA analysis and close inspection of seeds from the bird's gut, the team was able to identify the type of mistletoe that the bird eats. This information gives researchers a new perspective on this bird's ecological needs and habitat preferences.With more detailed information about the bird's diet and ecology now available, people hoping to spot the new species will have a better idea of when and where to look, Saucier said. Despite being small, gray and keeping mostly to the treetops, the Spectacled Flowerpecker has already been seen in many locations across the island, suggesting it may be widespread. "We think that wherever primary forest and mistletoe occur, there's a good chance this bird could be there," Saucier said.The researchers hope their discovery will bring attention to the unexplored diversity that remains in the forests of Borneo -- and the importance of conserving these threatened ecosystems. Protecting the region's natural resources from logging, palm plantations and other sources of deforestation is critical to preserve endemic species, as well as the homes and livelihoods of the island's indigenous people.Saucier added that the knowledge and skills of the local people were essential in enabling the research team to access the wildlife preserve and animals for their study. The scientific name that the team chose for the Spectacled Flowerpecker, Support for this research was provided by Holt Thrasher, Kevin Kimberlin and David B. Ford.
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New Species
| 2,019 |
October 17, 2019
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https://www.sciencedaily.com/releases/2019/10/191017125235.htm
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Scientists discover new species of wasp-mimicking praying mantis
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Cleveland Museum of Natural History Director of Research & Collections and Curator of Invertebrate Zoology Dr. Gavin Svenson and former Case Western Reserve University graduate student, Henrique Rodrigues, have discovered a new species of praying mantis, described as the first known mantis species to conspicuously mimic a wasp. In addition, the new species joins one previously described species within a newly erected genus Vespamantoida. The results of the team's findings were published today in the online journal
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The new species, named "Typically, the majority of species differentiation is discovered and confirmed within a lab or collection setting," explains Dr. Svenson. "To have that rare eureka moment where you know you have found something new in the field is incredibly exciting."The mantis exhibited a bright red-orange coloration, as well as the body structure, erratic locomotion patterns, and even antennae behavior typically associated with most wasp species. This apparent style of mimicry, known as Batesian mimicry, is a strategy in which a mostly harmless organism adopts the appearance, and occasionally the behaviors, of an organism known to pose a greater threat to would-be predators."In nature, when you are intentionally conspicuous, you are advertising something," says Dr. Svenson. "When you are a species that can be easily taken as prey, you advertise because you want predators to think that you are poisonous, or could injure them, or any combination of unpleasant factors that tell the predator to think twice before pursuing you."In the mantis world, mimicry of vegetation is a fundamental strategy, but wasp mimicry in adults is unique, and limited to just one family, of which Vespamantoida is now a part. Until the discovery of V. wherleyi, however, mantis mimicry strategies were theorized to aid the mantis primarily in hiding from predators, and occasionally in luring prey. The conspicuous appearance and behavior of V. wherleyi represent a novel form of defensive mimicry whereby the mantis imitates a harmful organism's natural defense signals to warn predators away. It is a strategy that is unique among known mantises."There are about 2,500 species of mantises described," says Dr. Svenson. "I'd put a bet on there being about 5,000. So, I think we're just halfway there. I think the most interesting thing about this family of mantises is the fact that most of the adults do mimic wasps, and that is quite unique for praying mantises. I think the next natural thing is to study the evolutionary biology of the lineage. If wasp mimicry is successful in this lineage, why has it not evolved in the other lineages as well? Why have no other species within the family evolved brightly colored wasp mimicry? We're just not sure."
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New Species
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October 17, 2019
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https://www.sciencedaily.com/releases/2019/10/191017101249.htm
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Sexual selection alone could spark formation of new species
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A new study by University of Pittsburgh researchers indicates animals that seek mates and fight rivals that resemble their parents could be behaving in ways that lead to the formation of new species.
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The study by Yusan Yang, a graduate student in the Richards-Zawacki Lab in the Department of Biological Sciences and associate professor Corinne Richards-Zawacki, examines behavioral imprinting -- the phenomenon of offspring learning a parent's appearance to choose future mates or distinguish rivals -- in the strawberry poison frog (This central American frog has a wide variety of color types. The mother frog raises their tadpoles by feeding them unfertilized eggs. This mother-offspring interaction, the team discovered, influences the behaviors of the offspring: females grow up to prefer mates that have the same color as their mother and males grow up to be more aggressive when their rival has the same color as their mother.The team developed a mathematical model to demonstrate how these imprinted behaviors can contribute to the formation of new species. Because of the imprinted preferences, females mate more with similar colored males, and less with differently colored males, which, over time, could lead to two color types becoming separate species."Sexual selection is traditionally thought of as a strong driving force for the formation of new species. But several theoretical models have suggested it was not incredibly likely to do so without natural selection or geographic separation," explained Yang."One of the reasons is because it is hard to maintain multiple mating types in the population. Usually, natural selection can serve the role, but our model suggests that imprinted male aggression can also do it. This means that with imprinting in both sexes, sexual selection on its own could potentially kick start speciation."The study was focused on amphibians, but the results could shed light on the evolution of many other animal species with imprinting, and in general where new species come from."Speciation is a key process in biology that has led to the amazing diversity of species we see today. How that happens is a fundamental question in evolution and one we've been trying to answer since the time of Charles Darwin," said Richards-Zawacki.
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New Species
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October 15, 2019
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https://www.sciencedaily.com/releases/2019/10/191015164702.htm
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Two new porcelain crab species discovered
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Two new porcelain crab species have been described in the
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Porcelain crabs belong to a highly diverse family of marine crustaceans, distributed in the shallow waters of oceans worldwide. They also are known as "false crabs," because they evolved a crab-like form independently of true crabs. A relatively large number of porcelain crab species are symbiotic with other organisms, allowing scientists to tell a story of a long-time relationship between species from distantly related taxa."Most porcelain crabs live on the hard substrates of shallow waters like the surface of corals or rocks overgrown by algae, microbes and decaying material," said STRI research associate Alexandra Hiller, co-author of the papers. "Others live as symbionts of invertebrates like sponges, anemones, sea urchins, polychaete worms and other crustaceans."The two recently described species are examples of these symbiotic porcelain crabs. Although initially mistaken for Despite the relatively high number of known symbiotic porcelain crab species, such as "Symbiotic species are thought to be more vulnerable to environmental challenges than free-living organisms," said Prof. Dr. Bernd Werding, from the Institut fur Tierokologie und Spezielle Zoologie der Justus-Liebig-Universitat Giessen, and co-author of the studies. "Their fate depends on the fate of their host, which may also be affected by local and global conditions and abrupt changes."
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New Species
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October 15, 2019
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https://www.sciencedaily.com/releases/2019/10/191015075314.htm
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Rare 'itinerant breeding' behavior revealed in California bird
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Reproduction and migration are the two most demanding tasks in a bird's life, and the vast majority of species separate them into different times of the year. Only two bird species have been shown to undertake what scientists call "itinerant breeding": nesting in one area, migrating to another region, and nesting again there within the same year, to take advantage of shifting food resources. New research just published in
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Scientists had known for years that some Phainopeplas breed in the desert in spring, where they feed on desert mistletoe berries, and others breed in woodlands in the summer, where a wider range of foods are available -- but could these actually be the same birds? To find out, Princeton University's Daniel Baldassarre, now an Assistant Professor at SUNY Oswego, and his colleagues captured 24 adult Phainopeplas breeding in the Mojave Desert in March and April 2017 and fitted them with tiny GPS tags. To download the GPS data and see where they went, they had to recapture the same birds. Fortunately, five of the 24 birds returned to the same site that fall, and all five tagged birds had migrated to coastal woodland habitats and back in the intervening months -- exactly where and when the itinerant breeding hypothesis predicted."Seeing the GPS tracks for the first time was amazing, but the biggest thrill for me was re-sighting the first tagged bird that returned to the capture site," says Baldassarre. "We were a bit unsure how likely they were to come back to the same spot, so to see that a tagged bird had returned was an exhilarating moment. When he hit the net it was like, okay, we're in business here."Circumstantial evidence has long raised suspicions that Phainopeplas might be itinerant breeders. Phainopeplas are vocal mimics, and birdwatchers had observed individual birds in desert habitats mimicking species found in woodland habitats and vice versa. The GPS data from this study still doesn't completely prove that Phainopeplas are itinerant breeders because the researchers were not able to directly observe any tagged birds nesting in coastal woodlands. However, Baldassarre and his colleagues were able to further support their conclusions with DNA analysis showing that desert breeders and woodland breeders are not genetically different."I approached this just thinking about it being a cool species and a rare behavior, but as I started to consider the bigger picture, I realized that the sort of flexibility that itinerant breeding species like this seem to be capable of is also interesting from a climate change perspective," says Baldassarre. "It suggests that they might be able to deal with climate change better than other birds. They're highly mobile, they can modulate their physiology to go between migratory and breeding periods quickly, and they can deal with different physical and social environments. It makes this interesting beyond just being a weird bird behavior."
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New Species
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October 10, 2019
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https://www.sciencedaily.com/releases/2019/10/191010142057.htm
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Key uncertainties identified for models of mosquito distribution in the US
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A computational analysis has identified key regions in the United States where model-based predictions of mosquito species distribution could be improved. Andrew Monaghan of the University of Colorado Boulder and colleagues present these findings in
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To address this issue, Monaghan and colleagues assessed and combined previously developed computational models to generate new predictions of the chances of finding Ae. aegypti and Ae. albopictus in each county in the contiguous United States. Then, they compared their estimates with real-world mosquito collection data from each county.The researchers found that existing models have gaps that had not previously been identified, despite the relatively high availability of mosquito data in the U.S. compared to other countries. They found high uncertainty of the models in predicting the presence of Ae. aegypti and Ae. albopictus across broad regions likely to be borderline habitats for these species. They also discovered key pockets where the models appear to be biased, such as the Florida panhandle and much of the Southwest for Ae. aegypti."By comparing analytical models and data, we identified key gaps in mosquito surveillance data and models," says senior author, Michael Johansson. "Understanding those limitations helps us to be better prepared for infectious disease threats today and to focus on key needs to be even better prepared tomorrow."The findings point to the need for additional data and improved models to advance understanding of the range of mosquito species and risk of disease transmission around the world. Johansson and colleagues are now organizing an ongoing collaborative project to systematically collect more mosquito data in the United States and analyse new models, shedding new light on species distribution.
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New Species
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October 9, 2019
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https://www.sciencedaily.com/releases/2019/10/191009142855.htm
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Meet Siamraptor suwati, a new species of giant predatory dinosaur from Thailand
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Fossils discovered in Thailand represent a new genus and species of predatory dinosaur, according to a study released October 9, 2019 in the open-access journal
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Carcharodontosaurs were a widespread and successful group of large predatory dinosaurs during the Jurassic and Cretaceous Periods and were important members of ecosystems on multiple continents. However, the fossil record of these animals is notably lacking from the Early Cretaceous of Asia, with no definite carcharodontosaurs known from Southeast Asia.In this study, Chokchaloemwong and colleagues describe fossil material from the Khok Kruat geologic formation in Khorat, Thailand, dating to the Early Cretaceous. These fossils include remains of the skull, backbone, limbs, and hips of at least four individual dinosaurs, and morphological comparison with known species led the authors to identify these remains as belonging to a previously unknown genus and species of carcharodontosaur which they named Phylogenetic analysis indicates that
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New Species
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October 9, 2019
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https://www.sciencedaily.com/releases/2019/10/191009132424.htm
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Reef fish caring for their young are taken advantage of by other fish
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Scroungers and parasites seem to show up in nature wherever life produces something useful, and that includes parental care. Among birds, for example, the practice of laying eggs in other birds' nests is surprisingly common.
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This phenomenon, known as brood parasitism, was unknown in coral reef fish because most marine fish don't provide any parental care at all. Now, however, biologists studying an unusual kind of coral reef fish that does care for its young have found that, sure enough, other fish are taking advantage of this to get free parental care for their offspring.Giacomo Bernardi, professor of ecology and evolutionary biology at UC Santa Cruz, went to the Philippines with his graduate students to study damselfish in the genus Altrichthys. Two species of Altrichthys were known to protect their young, and Bernardi's team discovered a third species that also provides parental care."It is extremely rare in coral reef fish," Bernardi said. "In most species, the larvae disperse and drift with the currents before they settle onto the reef, and 99 percent of them get eaten."As he was observing adult Altrichthys guarding their broods, Bernardi noticed that some of the young fish looked different from the others. Genetic tests revealed that the oddball fish belonged to a different species that does not provide parental care. More surpisingly, genetic testing of entire broods revealed that many Altrichthys parents were caring for mixed broods of young that were the same species but not offspring of the same parents."That was a complete surprise to me, and we only found it by doing the genetics," Bernardi said.To help him make sense of these findings, Bernardi turned to his UCSC colleague Bruce Lyon, a professor of ecology and evolutionary biology who studies brood parasitism in birds. They reported their findings in a paper published in the journal Molecular Ecology."It's kind of a mine field in terms of how to interpret this," Lyon said. "In birds or fish, there are two main ways you can end up with mixed broods -- either adoption, where young from outside the family get accepted into the brood, or brood parasitism, where an adult lays eggs in somebody else's nest."Bernardi's team found evidence of both. When the young of other species show up in Altrichthys broods, it appears to be the result of baby fish gaining protection by integrating themselves into a brood. In mixed broods of the same species, however, the researchers often found broods composed of two genetically different families of similar sizes, making brood parasitism (laying eggs in another pair's nest) a much more likely explanation."If it's not brood parasitism, then a whole clutch of baby fish would have to swim over and get adopted. That seems unlikely because the nests are far apart, and the mortality is enormous for unprotected babies," Bernardi said.The few times Bernardi collected parents for genetic sampling, the baby fish they had been guarding were eaten by predators almost immediately. "It doesn't look like the parents are aggressively defending their brood, but as soon as you remove them, predators move in within a matter of seconds. So the idea that a group of young fish would swim around and find another brood to integrate with seems very unlikely," he said.Genetic testing of the eggs in Altrichthys nests could provide definitive evidence of brood parasitism, but Bernardi said the nests are deep in the coral, and sampling them would be too destructive. "This place is pristine and gorgeous, and we would have to break a lot of live coral to get to the nests. But it's a crucial test, so I'd like to do some experiments with Altrichthys in tanks," he said.Fish of other species do get adopted into broods of Altrichthys, and Bernardi's observations suggest this may be an important survival strategy. One morning his team witnessed a large "recruitment event," when damselfish larvae that had been drifting in the currents all settled onto the reef in massive numbers."There were clouds of this one species, tens of thousands of baby fish, and over the next few days we saw the clouds get thinner and thinner as they got eaten, until eventually the only survivors were the ones that had integrated into groups of Altrichthys," Bernardi said. "I'm sure there were also some survivors hidden in the corals, but it suggests that adoption may play a significant role."According to Lyon, parental care and brood parasitism are closely connected in the tree of life. "In most taxonomic groups that have evolved parental care, some forms of reproductive parasitism also evolve," he said. "Given the extreme rarity of parental care in reef fish, it is very interesting that these species also show forms of reproductive parasitism like adoption and brood parasitism. When organisms evolve to produce some resource, if it's cheatable, evolution will produce a cheat."
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New Species
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October 8, 2019
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https://www.sciencedaily.com/releases/2019/10/191008125604.htm
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Meet the 'mold pigs,' a new group of invertebrates from 30 million years ago
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Fossils preserved in Dominican amber reveal a new family, genus and species of microinvertebrate from the mid-Tertiary period, a discovery that shows unique lineages of the tiny creatures were living 30 million years ago.
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The findings by George Poinar Jr. of the Oregon State University College of Science give a rare look at a heretofore unknown clade of invertebrates, along with their fungal food source and other animals that lived in their habitat.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, informally calls the new animals "mold pigs" for their resemblance to swine, and their diet. Scientifically, they are Sialomorpha dominicana, from the Greek words for fat hog (sialos) and shape (morphe).Invertebrate means not having a backbone, and invertebrates account for roughly 95 percent of animal species."Every now and then we'll find small, fragile, previously unknown fossil invertebrates in specialized habitats," Poinar said. "And occasionally, as in the present case, a fragment of the original habitat from millions of years ago is preserved too. The mold pigs can't be placed in any group of currently existing invertebrates -- they share characteristics with both tardigrades, sometimes referred to as water bears or moss pigs, and mites but clearly belong to neither group."The several hundred individual fossils preserved in the amber shared warm, moist surroundings with pseudoscorpions, nematodes, fungi and protozoa, Poinar said."The large number of fossils provided additional evidence of their biology, including reproductive behavior, developmental stages and food," he said. "There is no extant group that these fossils fit into, and we have no knowledge of any of their descendants living today. This discovery shows that unique lineages were surviving in the mid-Tertiary."The Tertiary period began 65 million years ago and lasted for more than 63 million years.About 100 micrometers long, the mold pigs had flexible heads and four pairs of legs. They grew by molting their exoskeleton and fed mainly on fungi, supplementing that food source with small invertebrates."No claws are present at the end of their legs as they are with tardigrades and mites," Poinar said. "Based on what we know about extant and extinct microinvertebrates, S. dominicana appears to represent a new phylum. The structure and developmental patterns of these fossils illustrate a time period when certain traits appeared among these types of animals. But we don't know when the Sialomorpha lineage originated, how long it lasted, or whether there are descendants living today."
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New Species
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October 1, 2019
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https://www.sciencedaily.com/releases/2019/10/191001132654.htm
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Glowing bacteria in anglerfish 'lamp' come from the water
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New research shows that female deep-sea anglerfish's bioluminescent bacteria -- which illuminate their "headlamp" -- most likely come from the water.
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Scientists who study these fish are still mostly in the dark about the bacteria, which share a symbiotic relationship with the fish. Researchers knew from an earlier study that, based on their genomes, these bacteria did not appear to be fully equipped to live on their own outside of a host."In previous work that I had done, we found for the symbionts of deep-sea anglerfish that the bacteria have undergone genomic reductions; they've lost a lot of genes, suggesting that they are probably obligately dependent on their host," said Tory Hendry, assistant professor of microbiology at Cornell University and the paper's senior author.A reduced genome is a hallmark of bacteria that live their whole lives inside a host and receive services and nutrients that they no longer need instructions to acquire. Such species then lack the genetic "software" to survive on their own.In the study, the researchers obtained previously collected specimens of seven species of anglerfish across six families. They also studied the only two species of bioluminescent bacteria known to live within the bulbs of anglerfish. While one species of bacteria was specifically only found in one species of fish, the other bacteria species was found in all six of the remaining species studied.The fish were each caught in different locations, from the Gulf of Mexico to the Cape Verde islands. While some were caught almost 20 years apart, the bacteria in the bulbs were 99% identical.Another study by collaborators in the DEEPEND Consortium revealed that anglerfish only acquire bacteria later in life once their light organ has developed. The bulb has a little pore in it, and the researchers wonder if the fish may spew bacteria into the environment once microbe populations grow, possibly to ensure that future generations of young fish have access to the luminous microbes in the water.
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New Species
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September 26, 2019
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https://www.sciencedaily.com/releases/2019/09/190926141715.htm
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Otherworldly worms with three sexes discovered in Mono Lake
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Caltech scientists have discovered a new species of worm thriving in the extreme environment of Mono Lake. This new species, temporarily dubbed
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Mono Lake, located in the Eastern Sierras of California, is three times as salty as the ocean and has an alkaline pH of 10. Before this study, only two other species (other than bacteria and algae) were known to live in the lake -- brine shrimp and diving flies. In this new work, the team discovered eight more species, all belonging to a class of microscopic worms called nematodes, thriving in and around Mono Lake.The work was done primarily in the laboratory of Paul Sternberg, Bren Professor of Biology. A paper describing the research appears online on September 26 in the journal The Sternberg laboratory has had a long interest in nematodes, particularly As nematodes are considered the most abundant type of animal on the planet, former Sternberg lab graduate students Pei-Yin Shih (PhD '19) and James Siho Lee (PhD '19) thought they might find them in the harsh environment of Mono Lake. The eight species they found are diverse, ranging from benign microbe-grazers to parasites and predators. Importantly, all are resilient to the arsenic-laden conditions in the lake and are thus considered extremophiles -- organisms that thrive in conditions unsuitable for most life forms.When comparing the new This suggests that nematodes may have a genetic predisposition for resiliency and flexibility in adapting to harsh and benign environments alike."Extremophiles can teach us so much about innovative strategies for dealing with stress," says Shih. "Our study shows we still have much to learn about how these 1000-celled animals have mastered survival in extreme environments."The researchers plan to determine if there are particular biochemical and genetic factors that enable nematodes' success and to sequence the genome of But beyond human health, studying extreme species like the nematodes of Mono Lake contributes to a bigger, global picture of the planet, says Lee."It's tremendously important that we appreciate and develop a curiosity for biodiversity," he adds, noting that the team had to receive special permits for their field work at the lake. "The next innovation for biotechnology could be out there in the wild. A new biodegradable sunscreen, for example, was discovered from extremophilic bacteria and algae. We have to protect and responsibly utilize wildlife."The paper is titled, "Newly Identified Nematodes from Mono Lake Exhibit Extreme Arsenic Resistance." Shih and Lee are co-first authors on the study; Shih is now a postdoctoral fellow at Columbia University and Lee is now a postdoctoral fellow at The Rockefeller University. In addition to Shih, Lee, and Sternberg, other co-authors are Ryoji Shinya of Meiji University in Japan, Natsumi Kanzaki of the Kansai Research Center in Japan, Andre Pires da Silva of the University of Warwick in the UK, former Caltech Summer Undergraduate Research Fellow student Jean Marie Badroos now of UC Berkeley, and Elizabeth Goetz and Amir Sapir of the University of Haifa in Israel. Funding was provided by the Amgen Scholars Program, the Leverhulme Trust, and the Howard Hughes Medical Institute.
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New Species
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September 25, 2019
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https://www.sciencedaily.com/releases/2019/09/190925123420.htm
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The almond and peach trees genomes shed light on the differences between these close species
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The almond tree and the peach tree are two well-known species, since human beings have been eating their fruit (peach) or seed (almond) for thousands of years. Although at first sight the products of these trees may seem to be very different, both species are part of the
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The knowledge of the almond tree's genome will be a very important tool in the improvement of the species. "For example, this information will enable us to look for more productive and more disease-resistant varieties and also rule out those that bear bitter almonds more easily," explains Pere Arús, an IRTA researcher at CRAG. Arús led the study that is now published in The comparison of the genome of the 'Texas' almond tree variety ? the sequencing of which involved the team of Tyler Alioto of the Centro Nacional de Análisis Genòmico (CNAG-CRG), part of the Centre for Genomic Regulation (CRG) ? and the peach tree genome places the divergence of both species six million years in the past. The results are consistent with the existing hypothesis that places the existence of a common ancestor of these The authors of the paper found, as was to be expected, that the genomes of the almond tree and the peach tree have a high degree of conservation, and they investigated the extent of the differences between them and whether they could be accounted for by the action of the transposons.Transposons are pieces of DNA with the capacity to change position within a genome and proliferate, jumping from one chromosome to another, and taking up a major part of the genome. In this transposition process, these mobile genetic elements may create mutations or change the genome's local properties, thus affecting gene regulation. There has been a great deal of discussion regarding the utility of these mobile genetic elements since Barbara McClinktock predicted their existence almost 70 years ago and for which she received the Nobel Prize in Medicine and Physiology in 1983.The results of the analysis of the almond tree and peach tree genomes show that approximately 37% of their genome is comprised of mobile elements and that some of the genes that play a key role in the differentiation of both species are affected by the presence of these elements. "In this study, we discovered that the recent history of the transposons of the almond tree and the peach tree could lie at the basis of many of the important differences between both species," explains Josep M. Casacuberta, a CSIC investigator at CRAG expert in mobile genetic elements and study co-leader. "Although increasingly more studies have demonstrated the key role of the mobile elements in evolution, the comparison of the almond tree and the peach tree, both species with distinct characteristics but with very closely-related genomes, provides unique insights into the impact of the transposons on the initial steps in the separation of the species," continuous Casacuberta.Most of the
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New Species
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September 25, 2019
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https://www.sciencedaily.com/releases/2019/09/190925075728.htm
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Private boats in the Mediterranean have extremely high potential to spread alien species
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This is the first study in the Mediterranean to combine boat and marina sampling data with crew surveys to better understand the role these boats play in spreading alien species. The researchers from the University of Pavia, Italy found that boats traveling to new marinas were likely to be transporting alien species in the biofouling: living growth on submerged areas of the vessel.
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The Mediterranean is a marine biodiversity hotspot, having the highest number of species for its size on the planet as well as the highest number of alien species. Invertebrate spawning occurs in the summer months, coinciding with the annual peak in recreational boating, making boats ideal carriers."Boats which have visited Eastern Mediterranean marinas had an especially high risk of spreading alien species due to the closer proximity to the Suez Canal, where most alien species enter the Mediterranean" said Aylin Ulman, lead author of the study.The biggest predictors of high species richness on boats were visible biofouling in niche areas such as ladders and propellers combined with longer elapsed time since a professional clean. Many boats only had small clumps of visible biofouling, but these could be hosting as many eleven alien species.Biofouling is not currently regulated in the Mediterranean, which Aylin Ulman said needs to change, "Biofouling is a major vector for the spread of marine alien species in the Mediterranean and needs regulation. To inhibit further spreading, marine pontoons should be cleaned regularly, and incoming vessels to marinas should be screened to determine if they require professional cleaning."Even after boats have been professionally cleaned, the researchers found that colonisation of alien species occurs rapidly. This is likely due to niche areas getting missed during cleans. The authors advise that these areas should be given special attention.Global management of biofouling is currently under consideration by the International Maritime Organization (IMO). The project supervisor, Agnese Marchini is presenting the findings of this study to the 1st GEF-UNDP-IMO GloFouling R&D Forum and Exhibition on Biofouling Management in October in Melbourne, Australia, to inform stakeholders around this.In the study the researchers sampled 601 boats and surveyed the crews to gather information on travel histories and time since the last clean. This took place at 25 marinas across six countries in Western, Central and Eastern Mediterranean.Samples from the boats were collected by scuba diving, snorkelling or when the boat was on land. They collected and identified macroinvertebrates including species of annelids, molluscs, tunicates, crustaceans and bryozoans.Aylin Ulman warned that "the actual number of alien species could be much more than were found in this study since macroalgae were not identified here due to time limitations." She also added that due to funding limitations "data was not collected from the Southern Mediterranean countries."On further research into alien species and recreational boating in the Mediterranean Aylin Ulman said "Longtime colleague Jasmine Ferrario at the University of Pavia is using this extensive dataset on alien species to build a model to identify high-risk marinas using environmental factors and marina characteristics. Some new marinas are now being sampled to validate the model."
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September 17, 2019
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https://www.sciencedaily.com/releases/2019/09/190917193635.htm
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One of world's oldest bird species found in Waipara, New Zealand
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The ancestor of some of the largest flying birds ever has been found in Waipara, North Canterbury.
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Bony-toothed birds (Pelagornithids), an ancient family of huge seafaring birds, were thought to have evolved in the Northern Hemisphere -- but that theory has been upended by the discovery of the family's oldest, but smallest member in New Zealand.At 62 million-years-old, the newly-discovered 'While its descendants were some of the biggest flying birds ever, with wingspans of more than 5 metres, 'The seabird fossil was identified by the same team that recently announced the discovery of a 1.6 metre-high giant penguin from the same site.Amateur palaeontologist Leigh Love found the partial 'Fellow amateur Alan Mannering prepared the bones, and a team comprising Love, Mannering, Canterbury Museum Curators Dr Paul Scofield and Dr Vanesa De Pietri and Dr Gerald Mayr of Senckenberg Research Institute and Natural History Museum in Frankfurt, Germany, described 'Dr Scofield says the age of the fossilised bones suggests pelagornithids evolved in the Southern Hemisphere. "While this bird was relatively small, the impact of its discovery is hugely significant in our understanding of this family. Until we found this skeleton, all the really old pelagornithids had been found in the Northern Hemisphere, so everyone thought they'd evolved up there.""New Zealand was a very different place when 'Protodontoperyx' were in the skies. It had a tropical climate -- the sea temperature was about 25 degrees so we had corals and giant turtles," he adds.Dr Mayr says the discovery of 'Later pelagornithid species evolved to soar over oceans with some species measuring up to 6.4 metres across the wings. 'Dr De Pietri says "because 'The last pelagornithid species died out around 2.5 million years ago, just before modern humans evolved.The Waipara Greensand site where the 'Some of these discoveries, including the 'This research was funded by the Royal Society of New Zealand's Marsden Fund.
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New Species
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September 17, 2019
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https://www.sciencedaily.com/releases/2019/09/190917193621.htm
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March of the multiple penguin genomes
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Published today in the open-access journal
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Penguins are a diverse order of species that span the Southern hemisphere, ranging from the Galápagos Islands on the equator, to the oceanic temperate forests of New Zealand, to the rocky coastlines of the sub-Antarctic islands, finally reaching the sea-ice around Antarctica. This iconic bird group have transitioned from flying seabirds to powerful, flightless marine divers. With their specialized skin and feathers and an enhanced thermoregulation system they are able to inhabit environments from the extreme cold Antarctic sea ice to the tropical Galápagos Islands.These birds also serve as the figurative "canary in a coal mine"; warning of environmental and climate change. Many penguin populations have experienced rapid declines in recent decades, some having extreme population drops, such as the crash of the King penguin population, which has declined by 88% in just 3 decades. And more penguin species are predicted to decline in the near future. The dwindling populations have been linked to climate warming, environmental degradation, exploitation of the marine environment, fisheries bycatch, pollution, and the introduction of exotic predators. Penguins have thus become the focus of many ecosystem monitoring studies. Having high-quality genomes sequences of all extant penguin species serves as an outstanding new resource for understanding the specific reasons for species population loss.Author Theresa Cole from the University of Otago in New Zealand says of this work: "The population history of different penguin species can be seen in their genome. We will provide new insights into the population history of all penguins over dramatic climate events, to predict population trends under future climate change scenarios. This research will help us understand how future climate change may affect other species, to help us develop conservation strategies."As with the work done on Darwin's finches, studying the radiation of the 20 penguin species provides similar enlightening case study for researching unique penguin morphological and physiological adaptations. The consortium are also sequencing the genomes of recently extinct penguin taxa, as well as undertaking population genomic studies using multiple genomes per species.Senior author Guojie Zhang from the University of Copenhagen, BGI, and Kunming Institute of Zoology says of this: "The penguin ancestor experienced rapid radiation leading to the current approximate 20 extant species, accompanied by many ancient lineages that are now extinct. The radiation of penguin thus provides an excellent example for the study of speciation."There were logistical challenges to get hold of high-quality specimens for all of these species as many come from some of the most inhospitable and far-flung corners of the globe. However, an additional challenge was cultural rather than technical. The process by which this consortium handled these sensitive issues serves as a model for building trust and collaboration with cultures that have equally important links to other native species.Co-author Bruce McKinlay from the New Zealand Department of Conservation highlights this, saying: "Genome research in New Zealand is currently moving into novel cultural contexts, especially for penguins, which are Taonga or treasured possessions in M?ori culture. As such, our consortium have undertaken rigorous indigenous consultation to sequence the genomes from six New Zealand Taonga species. We believe these genomes will be important for a cultural context."The goal of the first stage of the Penguin Genome Consortium project was purely to sequence high-quality genomes, but initial validation studies have demonstrated these genomes are already producing valuable insight into evolutionary history of the penguin tree of life and the evolutionary patterns of their adaptation to Antarctica. For example, an initial phylogenetic tree presented in this study demonstrates that penguins have adapted to Antarctica on multiple occasions.This and further comparative and evolutionary genomic analyses are currently being carried out, and the penguin genome consortium welcomes new members interested in joining the open consortium and contributing to this work. While this work is still underway early access to the 19 penguin genomes data has been provided, while the researchers ask groups intending to use this data for similar cross-species comparisons to follow the long running Fort Lauderdale and Toronto rules.
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New Species
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September 11, 2019
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https://www.sciencedaily.com/releases/2019/09/190911091350.htm
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Nature versus nurture in microorganisms
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A West Virginia University researcher used science and data to solve the timeless argument of nature versus nurture -- at least when it comes to microorganisms.
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Ember Morrissey, assistant professor of environmental microbiology in the Davis College of Agriculture, Natural Resources and Design, uncovered that nature significantly affects how the tiny organisms under our feet respond to their current surroundings."We found that evolutionary history (nature) shapes the traits of microbes in the soil more than their local environment (nurture)," she said. "I'm hopeful that we can use that information to make predictions about undiscovered species and organisms."Microorganisms cycle nutrients and play a vital role in the carbon cycle. According to Morrissey, understanding them better will help inform decisions related to fighting climate change."Soils contains more carbon than what is found in the atmosphere and plants," she explained. "Microorganisms break down and consume this carbon as they live and grow, converting it into the greenhouse gas carbon dioxide. Consequently, the activity of microorganisms in soil has the potential to alleviate or worsen climate change, so we need to form predictions regarding their activities."Her research focused on four different ecosystems in Arizona that varied in temperature and moisture. Measuring growth rate and carbon assimilation rate, Morrissey and her team discovered patterns in the biodiversity of soil microorganisms in each ecosystem.They were able to identify hundreds of species present at all four sites and assess their evolutionary history. In some families -- or groups of evolutionarily-related species -- all member species grew quickly while in others they grew slowly.According to Morrissey, this pattern of growth indicates that evolutionary history is a significant factor in determining the function of microbes."This enabled us to decide whether the functional traits of microorganisms are determined more by their evolutionary history or local environment," she said. "Because the activity of species within a family are similar, and consistent across environmental variation, we may be able to generalize about how a species is likely to behave in a variety of environments based on what family it belongs to."Morrissey's goal is to better understand microbial activity in the environment to help scientists predict how ecosystems respond to change. With more accurate predictions, they can help manage ecosystems to mitigate some of the human impacts on the environment."I think it is important for people to be aware that the soil under their feet is alive and is playing a really important role in determining the health of our ecosystems," she said. "Microbes in the soil respond to all the different ways humans are changing the environment."
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New Species
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September 10, 2019
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https://www.sciencedaily.com/releases/2019/09/190910134323.htm
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Electric eel produces highest voltage discharge of any known animal
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South American rivers are home to at least three different species of electric eels, including a newly identified species capable of generating a greater electrical discharge than any other known animal, according to a new analysis of 107 fish collected in Brazil, French Guiana, Guyana and Suriname in recent years.
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Scientists have known for more than 250 years that electric eels, which send electricity pulsing through the water to stun their prey, live in the Amazon basin. They are widely distributed in swamps, streams, creeks, and rivers across northern South America, and have long been thought to belong to a single species. With modern genetic and ecological analyses, however, researchers at the Smithsonian's National Museum of Natural History have discovered that electric eels in the Amazon basin belong to three different species that evolved from a shared ancestor millions of years ago. The findings are reported Sept. 10 in the journal The identification of two new species of electric eel highlights how much remains to be discovered within the Amazon rainforest -- one of Earth's biodiversity hotspots -- as well as the importance of protecting and preserving this threatened environment, says study leader C. David de Santana, a research associate in the museum's division of fishes. "These fish grow to be seven to eight feet long. They're really conspicuous," he says. "If you can discover a new eight-foot-long fish after 250 years of scientific exploration, can you imagine what remains to be discovered in that region?"About 250 species of electricity-generating fish are known to live in South America, although electric eels (which actually are fish with a superficial eel-like appearance) are the only ones that use their electricity to hunt and for self-defense. Like other electric fishes, they also navigate and communicate with the electricity they produce. Electric eels inspired the design of the first battery in 1799, and as researchers have learned more about how they generate enough electricity to stun a large animal, scientists and engineers have gained new ideas about how to improve technology and possibly even treat disease.Smithsonian scientists have been collaborating with researchers at the University of São Paulo's Museum of Zoology in Brazil and other institutions around the world to explore the diversity of the eels and other electric fishes in South America. As part of that effort, de Santana closely examined the electric eel specimens he and his colleagues had collected in the Amazon over the last six years.All the specimens looked pretty much the same. Finding no external features on the fish that clearly distinguished different groups on first glance, de Santana turned to the animals' DNA, and found genetic differences that indicated his 107 specimens represented three different species. Reexamining the animals with the genetic results in hand, he found subtle physical differences corresponding to the three genetic groups. He determined that each species has its own unique skull shape, as well as defining characteristics on the pectoral fin and a distinctive arrangement of pores on the body.Each species has its own geographic distribution, too. The long recognized Based on genetic comparisons, de Santana and colleagues determined that two groups of electric eels began to evolve in South America about 7.1 million years ago. One, the common ancestor of According to the analysis, De Santana says the previously overlooked diversity his team discovered is exciting since it creates new opportunities to investigate how animals generate high-voltage electricity by sequencing and comparing their genomes. Because the three species of electric eels diverged from one another so long ago, they may have evolved unique systems for electrogenesis, and, in the case of
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New Species
| 2,019 |
September 9, 2019
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https://www.sciencedaily.com/releases/2019/09/190909104656.htm
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New results on fungal genetics
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Several fungal species from the order Trichosporonales are of interest for industrial applications because they might be used for the production of biofuels. However, to explore their biotechnological potential it is necessary to learn more about their biology. An team of researchers led by Associate Professor Minou Nowrousian from the Department of Molecular and Cellular Botany of the Ruhr-University Bochum (RUB) has now analyzed 24 genomes of Trichosporonales fungi with a focus on genes that are important for sexual development. The study was performed in collaboration with the laboratory of Prof. Dr. Joseph Heitman from Duke University, USA, who has an ongoing collaboration with the RUB and has been a visiting professor with the RUB Research School
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The researchers published their results in the journal The genes that regulate sexual development in fungi are called mating type genes. They must differ between mating partners to allow successful cell fusion. In fungi of the basidiomycetes, which comprise the Trichosporonales, but also well-known mushrooms like the button mushroom, the mating type genes are often located at two different positions within the genome, which are called mating type loci. However, there are species with fused mating type loci, where both loci are physically linked on the same chromosome. The chromosomes that contain the mating type loci often have functions similar to sex chromosomes in animals and plants.The team from Germany and the USA has analyzed the mating type genes in 24 species of the order Trichosporonales, and discovered physically linked mating type loci with previously unknown features.The results showed that all analyzed Trichosporonales species have fused mating type loci with properties that are different than the properties of previously analyzed fused mating type loci in other basidiomycetes. Both the order of the genes within the fused loci as well as the sequences of the genes are highly conserved, in contrast to fused mating type loci in other basidiomycetes. This is unusual, because mating type as well as sex chromosomes tend to degenerate during evolution. The mechanisms that stabilize the Trichosporonales mating type loci will be analyzed in future studies.
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New Species
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September 5, 2019
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https://www.sciencedaily.com/releases/2019/09/190905094056.htm
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Diversity increases ecosystem stability
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Forests with a large variety of species are more productive and stable under stress than monocultures: scientists from the University of Freiburg have confirmed this with data from the world's oldest field trial on the diversity of tropical tree species. The team around PhD student Florian Schnabel has published its results in the journal
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As the researchers state, there is increasing scientific evidence of positive relationships between the diversity of tree species and ecosystem functioning. However most studies on this relationship to date have used either data from forests where the influence of biodiversity cannot be separated from other factors, or from young planted experiments, which do not provide data on longer periods of time. Therefore, the Freiburg research team analyzed data from the Sardinilla experiment which was planted in Panama in 2001. This experiment covers 22 plots planted with one, two, three or five native tree species. Since these grow at different rates, the plots with a greater variety of species also have a greater structural diversity with regard to the height and diameter of the trees. Annual data on the size and height of the trees, which are seen as indicators of the productivity and stability of the ecosystem, come from the period 2006 to 2016.The study concludes that mixtures of two and three tree species have on average a 25 to 30 per cent higher productivity than monocultures, and those with five species even 50 percent higher. The differences during a severe dry period caused by the tropical climate phenomenon El Niño were especially pronounced. This indicates that forests with a greater diversity of tree species are not only more productive, but also more stable and resilient under drought stress -- the researchers believe this is a particularly important finding in view of global climate change. In the context of initiatives that aim to reduce atmospheric COAccording to the team, these results offer new insights into the dynamics of tropical plantation forests and emphasize the importance of analyses that cover a longer development period, since they contribute to a better understanding of the connections between the diversity, productivity and stability of ecosystems. The study is based on Florian Schnabel's master thesis, for which he will be receiving the Hansjürg-Steinlin prize, a University of Freiburg award for new talent, in October at the start of the 2019/20 academic year. Florian Schnabel is now a PhD student involved in the TreeDì project at the German Centre for Integrative Biodiversity Research (iDiv) in Leipzig.
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New Species
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September 4, 2019
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https://www.sciencedaily.com/releases/2019/09/190904141302.htm
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Squirrels listen in to birds' conversations as signal of safety
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Grey squirrels eavesdrop on the chatter between nearby songbirds as a sign of safety. Birds chatter when they feel safe to communicate the absence of danger or share their location. This "chatter" from multiple bird species could therefore be a useful cue to other creatures that there is no imminent threat.
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To test this hypothesis, the researchers observed the behavior of 54 wild Eastern gray squirrels (Sciurus carolinensis) in public parks and residential areas in Ohio in response to threat, which they simulated by playing back a recording of the call of a red-tailed hawk (Buteo jamaicensis), a common predator of both squirrels and small birds. They followed the predator's call with a playback of either multi-species songbird bird chatter or ambient sounds lacking bird calls and monitored the behavior of each squirrel for 3 minutes.The researchers found that all squirrels showed an increase in predator vigilance behaviors, such as freezing, looking up, or fleeing, after they heard the hawk's call. However, squirrels that were played bird chatter afterwards performed fewer vigilance behaviors and returned to normal levels of watchfulness more quickly than squirrels that did not hear bird calls after the hawk's call. This suggests that the squirrels are able to tap into the casual chatter of many bird species as an indicator of safety, allowing them to quickly return to getting on with normal behaviors like foraging rather than remaining on high alert after a threat has passed.The authors add: "We knew that squirrels eavesdropped on the alarm calls of some bird species, but we were excited to find that they also eavesdrop on non-alarm sounds that indicate the birds feel relatively safe. Perhaps in some circumstances, cues of safety could be as important as cues of danger."
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New Species
| 2,019 |
September 3, 2019
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https://www.sciencedaily.com/releases/2019/09/190903113335.htm
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New whale species discovered along the coast of Hokkaido
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A new beaked whale species
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In a collaboration between the National Museum of Nature and Science, Hokkaido University, Iwate University, and the United States National Museum of Natural History, a beaked whale species which has long been called Kurotsuchikujira (black Baird's beaked whale) by local Hokkaido whalers has been confirmed as the new cetacean species Beaked whales prefer deep ocean waters and have a long diving capacity, making them hard to see and inadequately understood. The Stranding Network Hokkaido, a research group founded and managed by Professor Takashi F. Matsuishi of Hokkaido University, collected six stranded un-identified beaked whales along the coasts of the Okhotsk Sea.The whales shared characteristics of B. bairdii (Baird's beaked whale) and were classified as belonging to the same genus Berardius. However, a number of distinguishable external characteristics, such as body proportions and color, led the researchers to investigate whether these beaked whales belong to a currently unclassified species."Just by looking at them, we could tell that they have a remarkably smaller body size, more spindle-shaped body, a shorter beak, and darker color compared to known Berardius species," explained Curator Emeritus Tadasu K. Yamada of the National Museum of Nature and Science from the research team.In the current study, the specimens of this unknown species were studied in terms of their morphology, osteology, and molecular phylogeny. The results, published in the journal "There are still many things we don't know about Local Hokkaido whalers also refer to some whales in the region as Karasu (crow). It is still unclear whether This study was conducted in collaboration with multiple institutions. Dr. Shino Kitamura and Dr. Shuichi Abe of Iwate University carried out the DNA analyses while Dr. Tadasu K. Yamada and Dr. Yuko Tajima of the National Museum of Nature and Science made osteological specimens, morphological observations and detailed measurements to depict systematic uniqueness. Dr. Takashi F. Matsuishi and Dr. Ayaka Matsuda of Hokkaido University made the multivariate analyses. Dr. James G. Mead of Smithsonian Institution contributed to discussions related to systematic comparison.
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New Species
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August 28, 2019
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https://www.sciencedaily.com/releases/2019/08/190828140108.htm
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Clostridium difficile infections may have a friend in fungi
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The pathogen
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This week in "The development of Fungal taxa make up a tiny fraction of intestinal microbes -- between one-thousandth and one-tenth of one percent in healthy people. However, the new study suggests that even with low representation they may play an outsized role in dangerous infections."This discovery was just astounding to use, knowing that they're such a small percentage of organisms in the gut," said microbiologist and lead author Regina Lamendella, Ph.D., at Juniata College in Huntingdon, Pa.The researchers -- largely made up of a team of undergraduates from Juniata -- used high-throughput sequencing to identify fungal and bacterial populations in stool samples collected from 49 hospital patients. Eighteen of those had tested positive for The researchers also conducted bacterial gene expression analyses, which led them to identify new pathways -- or interactions between genes -- associated with The study suggests that patients with "Where we're headed next is to try to pin down the interaction between The researchers believe it's a research question worth pursuing. "The fungi could be a therapeutic target," Stewart said. "It would raise that possibility that we could repurpose already-approved antifungal drugs to treat
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New Species
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August 22, 2019
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https://www.sciencedaily.com/releases/2019/08/190822165028.htm
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The Paleozoic diet: Why animals eat what they eat
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What an animal eats is a fundamental aspect of its biology, but surprisingly, the evolution of diet had not been studied across the animal kingdom until now. Scientists at the University of Arizona report several unexpected findings from taking a deep dive into the evolutionary history of more than one million animal species and going back 800 million years, when the first animals appeared on our planet.
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The study, published in the journal Many species living today that are carnivorous, meaning they eat other animals, can trace this diet back to a common ancestor more than 800 million years ago.A plant-based, or herbivorous, diet is not the evolutionary driver for new species that it was believed to be. Closely related animals tend to share the same dietary category -- plant-eating, meat-eating, or both. This finding implies that switching between dietary lifestyles is not something that happens easily and often over the course of evolution.Cristian Román-Palacios, Joshua Scholl and John Wiens, all with the Department of Ecology and Evolutionary Biology at the UA, scoured the literature for data on the dietary habits of more than a million animal species, from sponges to insects and spiders to housecats. A species was classified as carnivorous if it feeds on other animals, fungi or protists (single-celled eukaryotic organisms, many of which live on bacteria). Species were classified as herbivorous if they depend on land plants, algae or cyanobacteria for food, and omnivorous if they eat a mixture of carnivorous and herbivorous diets.The scientists then mapped the vast dataset of animal species and their dietary preferences onto an evolutionary tree built from DNA-sequence data to untangle the evolutionary relationships between them."Ours is the largest study conducted so far that examines the evolution of diet across the whole animal tree of life," said doctoral student Román-Palacios, lead author of the paper. "We addressed three highly-debated and fundamental questions in evolutionary biology by analyzing a large-scale dataset using state-of-the-art methods."All species can be classified according to their evolutionary relationships, a concept that is known as phylogeny. Organisms are grouped into taxa, which define their interrelationships across several levels. For example, cats and dogs are different species but belong to the same order (carnivores). Similarly, horses and camels belong to a different order (ungulates.) Both orders, however, are part of the same class (mammals). On the highest level, animals are classified in phyla. Examples of animal phyla are arthropods (insects, crustaceans, spiders, scorpions and the like), mollusks (snails, clams and squid fall into this phylum), and chordates, which include all animals with a backbone, including humans.The survey suggests that across animals, carnivory is most common, including 63% of species. Another 32% are herbivorous, while humans belong to a small minority, just 3%, of omnivorous animals.The researchers were surprised to find that many of today's carnivorous species trace this diet back all the way to the base of the animal evolutionary tree, more than 800 million years, predating the oldest known fossils that paleontologists have been able to assign to animal origins with certainty."We don't see that with herbivory," said Wiens, professor of ecology and evolutionary biology and corresponding author of the study. "Herbivory seems to be much more recent, so in our evolutionary tree, it appears more frequently closer to the tips of the tree."So if the first animal was a carnivore, what did it prey on?The authors suggest the answer might lie with protists, including choanoflagellates: tiny, single-celled organisms considered to be the closest living relatives of the animals. Living as plankton in marine and freshwater, choanoflagellates are vaguely reminiscent of miniature versions of the shuttlecock batted back and forth during a game of badminton. A funnel-shaped collar of "hairs" surrounds a whip-like appendage called a flagellum whose rhythmic beating sucks a steady stream of water through the collar, filtering out bacteria and detritus that is then absorbed and digested. It is possible that the common ancestor of today's animals was a creature very similar to a choanoflagellate."The ancient creature that is most closely related to all animals living today might have eaten bacteria and other protists rather than plants," Wiens said.Turning to a plant-based diet, on the other hand, happened much more frequently over the course of animal evolution.Herbivory has traditionally been seen as a powerful catalyst for the origin of new species -- an often-cited example is the insects, with an estimated 1.5 million described species the most diverse group among the arthropods. Many new species of flowering plants appeared during the Cretaceous period, about 130 million years ago, and the unprecedented diversity of flowers is widely thought to have coincided with an increase in insect species taking advantage of the newly available floral bounty."This tells us that what we see in insects doesn't necessarily apply to other groups within the animal kingdom," Wiens said. "Herbivory may go hand in hand with new species appearing in certain taxa, but it clearly is not a universal driver of new species."The study also revealed that omnivorous ("eating everything") diets popped up rarely over the course of 800 million years of animal evolution, hinting at the possible explanation that evolution prefers specialists over generalists."You can be better at doing what you do if that is all you do," Wiens said. "In terrestrial vertebrates, for example, eating a diet of leaves often requires highly modified teeth and a highly modified gut. The same goes for carnivory. Nature generally seems to avoid the dilemma of being a jack-of-all-trades and master of none, at least for diets."This need for specialization might explain why omnivores, such as humans, are rare, according to the authors. It might also explain why diets have often gone unchanged for so long."There is a big difference between eating leaves all the time and eating fruits every now and then," Wiens said. "The specializations required to be an efficient herbivore or carnivore might explain why the two diets have been so conserved over hundreds of millions of years."
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New Species
| 2,019 |
August 22, 2019
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https://www.sciencedaily.com/releases/2019/08/190822081158.htm
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There are way more species of horseshoe bats than scientists thought
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Horseshoe bats are bizarre-looking animals with giant ears and elaborate flaps of skin on their noses that they use like satellite dishes. There are about a hundred different species of horseshoe bats -- and that number is only going to grow. By studying the DNA of horseshoe bat specimens in museum collections, scientists have discovered that there are probably a dozen new species of horseshoe bat that haven't been officially described yet.
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If you've never seen a horseshoe bat, you're missing out. Their comically large ears are only rivaled for wackiest feature by their nose leaves, little flaps of skin that spread outward from their faces like petals. If you grew up with siblings who would say, "That's you," when they saw an ugly creature on TV, they'd have a field day with horseshoe bats.But while they have faces only a biologist could love, horseshoe bats have caught the interest of scientists studying the bat family tree. There are more than 100 recognized species of horseshoe bats, and researchers now believe that number could be still higher. In a study published in MacArthur Curator of Mammals and senior author of the study Bruce Patterson says, to put it simply, "We found a lot more species than we thought were there.""Horseshoe bats are defined by the broad flap of skin on their upper lip. It serves as a radar dish for their echolocation calls," says Patterson. "I think they're totally bizarre and for students of biology that bizarreness is what makes them so fascinating."Terry Demos, post-doctoral researcher and lead author of the paper, also agrees that horseshoe bats are unique looking -- "You could say there's beauty in the elaborateness of the nose, I mean it is so intricate."The researchers wanted to study the bats because, despite being so rich in different species, little is known about their evolutionary history. East Africa has remained understudied, even though it's one of the most diverse regions in the world. For centuries, colonialism meant that European researchers were the only people with access to the land. Patterson and Demos hope that studies like this one will help equip local scientists with the tools they need to research their own land. "We're trying to understand evolutionary history in an understudied area," says Demos, "while also building in-country resources."The research team examined hundreds of bat specimens from the collections at the Field Museum and National Museums of Kenya. Using small samples of tissue, they sequenced the bats' DNA to see how closely related they were to each other, like 23AndMe testing on a species level.The genetic similarities and differences between the bats suggested that some distinctive groupings could be new species. Some of these new species may be what scientists call "cryptic" -- visually, they look very similar to species we already know about, but genetically, they're different enough to be considered their own separate species. These cryptic species were hiding in plain sight in the museums' collections, waiting to be discovered.While the study did suggest that there are more species of horseshoe bat than previously imagined, new species will not be officially named until the team carries out the next part of their research.To designate a new species, researchers will need to examine the bats' teeth and skulls to see how their physical traits differ. They'll also need to compare the bats' echolocation calls, since different bat species that live near each other often make their calls at different frequencies, like different channels on a walkie-talkie.The researchers are excited by the possibilities that come with rewriting the horseshoe bat family tree. "The implications of this study are really countless," says Patterson. "Bats eat insects that carry diseases, what are the implications of that? We can also use this to designate areas for conservation."
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New Species
| 2,019 |
August 19, 2019
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https://www.sciencedaily.com/releases/2019/08/190819164334.htm
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Global change is triggering an identity switch in grasslands
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Since the first Homo sapiens emerged in Africa roughly 300,000 years ago, grasslands have sustained humanity and thousands of other species. But today, those grasslands are shifting beneath our feet. Global change -- which includes climate change, pollution and other widespread environmental alterations -- is transforming the plant species growing in them, and not always in the ways scientists expected, a new study published Monday revealed.
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Grasslands make up more than 40 percent of the world's ice-free land. In addition to providing food for human-raised cattle and sheep, grasslands are home to animals found nowhere else in the wild, such as the bison of North America's prairies or the zebras and giraffes of the African savannas. Grasslands also can hold up to 30 percent of the world's carbon, making them critical allies in the fight against climate change. However, changes in the plants that comprise grasslands could put those benefits at risk."Is it good rangeland for cattle, or is it good at storing carbon?" said lead author Kim Komatsu, a grassland ecologist at the Smithsonian Environmental Research Center. "It really matters what the identities of the individual species are....You might have a really invaded weedy system that would not be as beneficial for these services that humans depend on."The new paper, a meta-analysis published in the They discovered grasslands can be surprisingly tough -- to a point. In general, grasslands resisted the effects of global change for the first decade of exposure. But once they hit the 10-year mark, their species began to shift. Half of the experiments lasting 10 years or more found a change in the total number of plant species, and nearly three-fourths found changes in the types of species. By contrast, a mere one-fifth of the experiments that lasted under 10 years picked up any species changes at all. Experiments that examined three or more aspects of global change were also more likely to detect grassland transformation."I think they're very, very resilient," said Meghan Avolio, co-author and assistant professor of ecology at Johns Hopkins University. "But when conditions arrive that they do change, the change can be really important."To the scientists' surprise, the identity of grassland species can change drastically, without altering the number of species. In half the plots where individual plant species changed, the total amount of species remained the same. In some plots, nearly all the species had changed."Number of species is such an easy and bite-sized way to understand a community...but what it doesn't take into account is species identity," Avolio said. "And what we're finding is there can be a turnover."For Komatsu, it's a sign of hope that most grasslands could resist the experimentally induced global changes for at least 10 years."They're changing slowly enough that we can prevent catastrophic changes in the future," she said.However, time may not be on our side. In some experiments, the current pace of global change transformed even the "control plots" that were not exposed to experimentally higher global change pressures. Eventually, many of those plots looked the same as the experimental plots."Global change is happening on a scale that's bigger than the experiments we're doing....The effects that we would expect through our experimental results, we're starting to see those effects occurring naturally," Komatsu said.
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New Species
| 2,019 |
August 15, 2019
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https://www.sciencedaily.com/releases/2019/08/190815140848.htm
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Bloodsucker discovered: First North American medicinal leech described in over 40 years
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Freshwater wetlands from Georgia to New York are home to a previously unrecognized species of medicinal leech, according to scientists at the Smithsonian's National Museum of National History. The new species, named Macrobdella mimicus, was first identified from specimens collected in southern Maryland, prompting a search through marshes and museum collections that ultimately revealed that the leech has long occupied a range that stretches throughout the Piedmont region of the eastern United States, between the Appalachian Mountains and the Atlantic Coast.
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An international team of museum scientists led by Anna Phillips, the museum's curator of parasitic worms, describe the new species in the Aug. 15 issue of the Leeches are parasitic worms, many of which feed on the blood of their hosts. In the 1700s and 1800s, physicians used leeches to treat a wide range of ailments, believing that by ridding a patient's body of bad blood, the parasites could cure headaches, fevers and other conditions. Any leech that readily feeds on humans is considered a medicinal leech, although in North America most leeches used for bloodletting were imported from Europe, leaving native species relatively undisturbed.Phillips and her colleagues have been exploring the diversity of medicinal leeches in North America for years. When she returned to the museum from a 2015 field expedition with several orange-spotted, olive-green leech specimens she had collected from a Maryland swamp, she and her team assumed they belonged to a familiar species called M. decora, a leech that is thought to live throughout a large swath of the northern United States. But DNA sequencing revealed otherwise.Examining the specimens' genomes at key regions used for species identification, Ricardo Salas-Montiel, a graduate student at the National Autonomous University of Mexico, found significant differences from the DNA of M. decora. The molecular discrepancy was surprising, but when the scientists took a closer look at the newly collected leeches, they found a physical difference that distinguished them from M. decora, as well. Like M. decora, the new leeches have multiple reproductive pores along the bottom of their bodies, known as gonopores and accessory pores. In the new leeches, the gonorpores and accessory pores were located in a different position relative to each other.A subsequent field outing led to the team finding more leeches from South Carolina that shared the same accessory pore positioning. "Then we sequenced [their DNA], and they all came out more closely related to the leeches we had found in Maryland than to anything else known to science," Phillips said.Phillips quickly retrieved dozens of North American leeches stored in the Smithsonian's parasite collection and examined their accessory pores. "All of a sudden, I started finding these things everywhere," she said. Leeches with the unique pore positioning had been found in locations from northern Georgia to Long Island and preserved in the museum's collection for years. The oldest, Phillips said, dated back to 1937.From there, Phillips expanded her search, scouring parasite collections at the North Carolina Museum of Natural Sciences and the Virginia Museum of Natural History, pinpointing additional places where the leech had been found in the past. She and her team also found fresh specimens in Georgia and North Carolina and used DNA sequencing to confirm their close relationship to the others.Each specimen added to the team's understanding of the leech's history in the region and its geographical range. Their molecular, geographical and morphological data suggest the M. mimicus occupies a sliver of the eastern United States that is nestled between the ranges of two other medicinal leech species, Phillips said. The historical record from the museums' collections, with specimens spanning 63 years, adds another critical layer of information, confirming that the species was not recently introduced to the area and does not represent a newly evolved species. "It's been here this whole time," she said. "We just hadn't looked at it in this new way."Funding for this research was provided by the Smithsonian, the National Autonomous University of Mexico, the Natural Sciences and Engineering Research Council of Canada, the Royal Ontario Museum and the Olle Engkvist Byggmästare Foundation in Sweden.
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New Species
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August 14, 2019
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https://www.sciencedaily.com/releases/2019/08/190814140500.htm
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AI used to test evolution's oldest mathematical model
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Researchers have used artificial intelligence to make new discoveries, and confirm old ones, about one of nature's best-known mimics, opening up whole new directions of research in evolutionary biology.
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The researchers, from the University of Cambridge, the University of Essex, the Tokyo Institute of Technology and the Natural History Museum London used their machine learning algorithm to test whether butterfly species can co-evolve similar wing patterns for mutual benefit. This phenomenon, known as Müllerian mimicry, is considered evolutionary biology's oldest mathematical model and was put forward less than two decades after Darwin's theory of evolution by natural selection.The algorithm was trained to quantify variation between different subspecies of Heliconius butterflies, from subtle differences in the size, shape, number, position and colour of wing pattern features, to broad differences in major pattern groups.This is the first fully automated, objective method to successfully measure overall visual similarity, which by extension can be used to test how species use wing pattern evolution as a means of protection. The results are reported in the journal The researchers found that different butterfly species act both as model and as mimic, 'borrowing' features from each other and even generating new patterns."We can now apply AI in new fields to make discoveries which simply weren't possible before," said lead author Dr Jennifer Hoyal Cuthill from Cambridge's Department of Earth Sciences. "We wanted to test Müller's theory in the real world: did these species converge on each other's wing patterns and if so how much? We haven't been able to test mimicry across this evolutionary system before because of the difficulty in quantifying how similar two butterflies are."Müllerian mimicry theory is named after German naturalist Fritz Müller, who first proposed the concept in 1878, less than two decades after Charles Darwin published On the Origin of Species in 1859. Müller's theory proposed that species mimic each other for mutual benefit. This is also an important case study for the phenomenon of evolutionary convergence, in which the same features evolve again and again in different species.For example, Müller's theory predicts that two equally bad-tasting or toxic butterfly populations in the same location will come to resemble each other because both will benefit by 'sharing' the loss of some individuals to predators learning how bad they taste. This provides protection through cooperation and mutualism. It contrasts with Batesian mimicry, which proposes that harmless species mimic harmful ones to protect themselves.Heliconius butterflies are well-known mimics, and are considered a classic example of Müllerian mimicry. They are widespread across tropical and sub-tropical areas in the Americas. There are more than 30 different recognisable pattern types within the two species that the study focused on, and each pattern type contains a pair of mimic subspecies.However, since previous studies of wing patterns had to be done manually, it hadn't been possible to do large-scale or in-depth analysis of how these butterflies are mimicking each other."Machine learning is allowing us to enter a new phenomic age, in which we are able to analyse biological phenotypes -- what species actually look like -- at a scale comparable to genomic data," said Hoyal Cuthill, who also holds positions at the Tokyo Institute of Technology and University of Essex.The researchers used more than 2,400 photographs of Heliconius butterflies from the collections of the Natural History Museum, representing 38 subspecies, to train their algorithm, called 'ButterflyNet'.ButterflyNet was trained to classify the photographs, first by subspecies, and then to quantify similarity between the various wing patterns and colours. It plotted the different images in a multidimensional space, with more similar butterflies closer together and less similar butterflies further apart."We found that these butterfly species borrow from each other, which validates Müller's hypothesis of mutual co-evolution," said Hoyal Cuthill. "In fact, the convergence is so strong that mimics from different species are more similar than members of the same species."The researchers also found that Müllerian mimicry can generate entirely new patterns by combining features from different lineages."Intuitively, you would expect that there would be fewer wing patterns where species are mimicking each other, but we see exactly the opposite, which has been an evolutionary mystery," said Hoyal Cuthill. "Our analysis has shown that mutual co-evolution can actually increase the diversity of patterns that we see, explaining how evolutionary convergence can create new pattern feature combinations and add to biological diversity."By harnessing AI, we discovered a new mechanism by which mimicry can produce evolutionary novelty. Counterintuitively, mimicry itself can generate new patterns through the exchange of features between species which mimic each other. Thanks to AI, we are now able to quantify the remarkable diversity of life to make new scientific discoveries like this: it might open up whole new avenues of research in the natural world."
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New Species
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August 14, 2019
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https://www.sciencedaily.com/releases/2019/08/190814101642.htm
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Monster penguin find in Waipara, New Zealand
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A new species of giant penguin -- about 1.6 metres tall -- has been identified from fossils found in Waipara, North Canterbury.
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The discovery of A team comprising Canterbury Museum curators Dr Paul Scofield and Dr Vanesa De Pietri, and Dr Gerald Mayr of Senckenberg Natural History Museum in Frankfurt, Germany, analysed the bones and concluded they belonged to a previously unknown penguin species.In a paper published this week in Canterbury Museum Senior Curator Natural History Dr Paul Scofield says finding closely related birds in New Zealand and Antarctica shows our close connection to the icy continent."When the Crossvallia species were alive, New Zealand and Antarctica were very different from today -- Antarctica was covered in forest and both had much warmer climates," he says.The leg bones of both Crossvallia penguins suggest their feet played a greater role in swimming than those of modern penguins, or that they hadn't yet adapted to standing upright like modern penguins.Dr Gerald Mayr says the Waipara Greensand is arguably the world's most significant site for penguin fossils from the Paleocene Epoch. "The fossils discovered there have made our understanding of penguin evolution a whole lot clearer," he says. "There's more to come, too -- more fossils which we think represent new species are still awaiting description."Dr Vanesa De Pietri, Canterbury Museum Research Curator Natural History, says discovering a second giant penguin from the Paleocene Epoch is further evidence that early penguins were huge. "It further reinforces our theory that penguins attained a giant size very early in their evolution," she says.The fossils of several giant species, including This research was partly supported by the Royal Society of New Zealand’s Marsden Fund
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New Species
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August 13, 2019
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https://www.sciencedaily.com/releases/2019/08/190813102327.htm
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DNA tests of UK waters could help catch invasive species early
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A team of scientists from the University of Southampton, Bangor University and the National Oceanography Centre have discovered several artificially introduced species in the coastal waters of southern England, using a technique that could help the early detection of non-native species if adopted more widely.
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Among the species identified during the study was The researchers, led by Luke Holman, a PhD student at the University of Southampton, collected water and sediment from four marinas around the UK and analysed the DNA of each sample to determine which species had been present in the ecosystems.Organisms leave traces of their DNA in water systems through a variety of means, for example fish can lose scales and many species can release sperm or eggs during the spawning season. The team were able to extract this genetic material, known as environmental DNA (eDNA), and compare it to global DNA databases to identify the presence of species.Luke Holman said "We are enormously excited about the potential for eDNA in the detection of invasive species. This initial work gives us confidence that the technique could be invaluable both for catching invasions early on and also for monitoring the success of eradication efforts."There are many ways in which species that are not native to the UK arrive on our shores. They can be carried in ballast water tanks or on ship hulls from one international harbour to another, something especially common in places like Southampton. They can also hitch a lift on live fish stocks and oysters imported for British fish farms.In total the team identified 18 non-indigenous species across the four sampled marinas -- in Southampton Water, Anglesey, The Bristol Channel and the River Blackwater. The If not caught early, invasive species can have devastating effects on the country's native wildlife habitats. For example, Asian date mussels can alter sediment through the thread like cocoons they produce which weave together and change the seafloor from a muddy to a thick, sandy material. This in turn changes the creatures that inhabit the area.Luke Holman added "We know that the muddy flats of Southampton water and the Solent area provide a great deal of food for foraging birds so we should be worried about any species with an ability to change the sediment."eDNA metabarcoding surveys are increasingly common in biodiversity monitoring, but their use for the detection of invasive species remains limited and this study, published in the journal The team hopes to build on their research by providing guidance for routine monitoring of non-indigenous species to natural resource agencies both in the UK and elsewhere.
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New Species
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August 12, 2019
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https://www.sciencedaily.com/releases/2019/08/190812130914.htm
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Diarrhea-causing bacteria adapted to spread in hospitals
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Scientists have discovered that the gut-infecting bacterium
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Published in Often found in hospital environments, To understand how this bacterium is evolving, researchers collected and cultured 906 strains of Dr Nitin Kumar, joint first author from the Wellcome Sanger Institute, said: "Our large-scale genetic analysis allowed us to discover that The researchers found that this emerging species, named Dating analysis revealed that while Dr Trevor Lawley, the senior author from the Wellcome Sanger Institute, said: "Our study provides genome and laboratory based evidence that human lifestyles can drive bacteria to form new species so they can spread more effectively. We show that strains of Prof Brendan Wren, an author from the London School of Hygiene & Tropical Medicine, said: "This largest ever collection and analysis of
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New Species
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July 26, 2019
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https://www.sciencedaily.com/releases/2019/07/190726094638.htm
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Ladies' choice: What drives faster, flashier formation of new animal species
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Evolution is actually a Sadie Hawkins dance, as new research shows females not only determine whether male animals develop bright colors, but also how fast new species develop.
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Research led by David Reznick, a UC Riverside biology professor, used fish often seen in pet stores, like guppies and swordtails, to test a hypothesis proposed by David and Jean Zeh at the University of Nevada, Reno. They predicted that the way mothers nurture their young influences the evolution of male traits, and Reznick's team is the first to find that the prediction was correct.A paper describing the research was published online today in Reznick was inspired to test the hypothesis while wandering the aisles of a pet store. Having spent more than a decade studying fish in the guppy family, he knew the ones in the store had a few things in common."The fish I saw that day all belong to the Poeciliidae family, which give birth to live young, rather than lay eggs. Some of them even have placentas, like mammals," Reznick said. "The ones offered for sale were only species with colorful males and all of those species had mothers that lack placentas. I wanted to know how having this type of mother might relate to the evolution of male traits."To answer his question, the team constructed a family tree using the DNA from more than 170 species in the Poeciliidae family of freshwater fish. They then mapped male and female traits on to the tree, reconstructing how male and female traits evolved throughout the fish family.For the fish without placentas, choosing a mate can be higher stakes."When mothers lack a placenta, they've already invested all they've got to give into the eggs prior to fertilization," Reznick said. "So, the mothers are picky about the males they choose."In fish where the mothers do have a placenta, it's a different game. In these species the eggs are smaller, and the mother hasn't invested a lot in them yet. A mother with a placenta has the ability to choose the father after mating, by influencing which sperm fertilize the eggs or possibly by aborting eggs she doesn't want.Analyzing the DNA tree of the fish family, the team found that the branches of the family tree with mothers who lack placentas are also those that give rise to the flashier males.The team then investigated a second prediction by David and Jean Zeh: that animals with placentas would diverge faster from one species into two. Here, Reznick's team proved this prediction wrong.Fish species with fancy males formed new species twice as fast as those with plain males. What this means is that in these fish, there is a connection between the way mothers nurture offspring, how they choose mates, and how fast their kind is destined to multiply into a new species.Members of the international research team included Andrew Furness of the University of Hull in the U.K., Bart Pollux of Wageningen University in the Netherlands, Robert Meredith of Montclair State University in New Jersey, as well as UC Riverside's Mark Springer.Though this analysis was performed using fish, Reznick says the underlying principles are broadly applicable throughout the animal kingdom. Many animals have evolved the ability to produce live young and many of these have evolved something like a placenta. He expects that the same connections between evolution of male and female traits and speciation rate are waiting to be discovered.
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New Species
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July 25, 2019
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https://www.sciencedaily.com/releases/2019/07/190725102935.htm
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Revolutionary method could bring us much closer to the description of hyperdiverse faunas
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Two hundred and sixty-one years ago, Linnaeus formalized binomial nomenclature and the modern system of naming organisms. Since the time of his first publication, taxonomists have managed to describe 1.8 million of the estimated 8 to 25 million extant species of multicellular life, somewhere between 7% and 22%. At this rate, the task of treating all species would be accomplished sometime before the year 4,000. In an age of alarming environmental crises, where taking measures for the preservation of our planet's ecosystems through efficient knowledge is becoming increasingly urgent, humanity cannot afford such dawdling.
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"Clearly something needs to change to accelerate this rate, and in this publication we propose a novel approach that employs only a short sequence of mitochondrial DNA in conjunction with a lateral image of the holotype specimen," explain the researchers behind a new study, published in the open-access journal In standardized practices, it is required that experts conduct plenty of time- and labor-consuming analyses, in order to provide thorough descriptions of both the morphology and genetics of individual species, as well as a long list of characteristic features found to differentiate each from any previously known ones. However, the scientists argue, at this stage, it is impossible to pinpoint distinct morphological characters setting apart all currently known species from the numerous ones not yet encountered. To make matters worse, finding human and financial resources for performing this kind of detailed research is increasingly problematic.This holds especially true when it comes to hyperdiverse groups, such as ichneumonoid parasitoid wasps: a group of tiny insects believed to comprise up to 1,000,000 species, of which only 44,000 were recognised as valid, according to 2016 data. In their role of parasitoids, these wasps have a key impact on ecosystem stability and diversity. Additionally, many species parasitise the larvae of commercially important pests, so understanding their diversity could help resolve essential issues in agriculture.Meanwhile, providing a specific species-unique snippet of DNA alongside an image of the specimen used for the description of the species (i.e. holotype) could significantly accelerate the process. By providing a name for a species through a formal description, researchers would allow for their successors to easily build on their discoveries and eventually reach crucial scientific conclusions."If this style were to be adopted by a large portion of the taxonomic community, the mission of documenting Earth's multicellular life could be accomplished in a few generations, provided these organisms are still here," say the authors of the study.To exemplify their revolutionary approach, the scientists use their paper to also describe a total of 18 new species of wasps in two genera (Zelomorpha and Hemichoma) known from Área de Conservación Guanacaste, Costa Rica. Currently, the team works on the treatment of related species, which still comprise only a portion of the hundreds of thousands that remain unnamed.
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New Species
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July 24, 2019
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https://www.sciencedaily.com/releases/2019/07/190724120206.htm
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Picky pathogens help non-native tree species invade
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Walk into a forest made of only native trees, and you probably notice many different tree species around you, with no one species dominating the ecosystem. Such biodiversity -- the variety of life and species in the forest -- ensures that each species gets a role to play in the ecosystem, boosting forest health and productivity. However, when non-native trees invade, they form dense groups of a single species of tree. This bucks conventional wisdom because, in theory, pathogens -- microscopic disease-causing organisms -- should prevent this from happening.
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Trees have many natural enemies, such as herbivores and insects that nibble on their leaves. But their main foes are invisible to the naked eye. In older forests especially, fungal pathogens evolve to attack the seedlings of certain tree species and, over time, accumulate in the soils around the adults, hindering the growth of their seeds. Seeds that fall far away from their parent typically survive better. The pathogens thus help dictate where native trees can grow and prevent some species from dominating others.This effect is part of the Janzen-Connell hypothesis, a widely accepted explanation for the promotion of biodiversity in forests. The theory was developed in the 1970s by ecologists Daniel Janzen and Joseph Connell, who said that species-specific herbivores, pathogens, or other natural enemies make the areas near a tree inhospitable for the survival of its seedlings. If one species becomes too abundant, there will be few safe places for its seedlings to survive, thus promoting the growth of other plant species within one area.Why, then, do introduced tree species often invade, outcompete, and displace native trees, even those of the same genus? The subject is the focus of a new study published in the Ecological Society of America's journal Aleksandra Wróbel, a PhD candidate in the Department of Systematic Zoology at Adam Mickiewicz University in Poland, says that the relationship between native trees and their enemy pathogens is a tightly co-evolved one; so tight, in fact, that pathogens may not be able to recognize or attack even closely-related introduced tree species. "Enemy-release" theory states that because introduced species are new to the ecosystem, they do not have enemies yet in the soil, and their seeds can fall densely and thrive, becoming invasive. This relaxation of the Janzen-Connell effect, says Wróbel, "gives non-native species a big competitive advantage over native species."To test how the intensity of the effect differs between tree species of a same genus, Wróbel and colleagues use greenhouse and field experiments to study two pairs of invasive and native tree species in Central Europe: boxelder (Under controlled conditions, the invasive species of both pairs fare better than their respective native cousins, avoiding attack by soil pathogens; they are released from the Janzen-Connell effect, giving them the survival advantage. However, under natural conditions, one genus pair (This study indicates that freedom from disease partially explains why non-native tree species dominate in areas where they are introduced. Improving understanding of the role that plant-soil interactions play in the establishment and spread of invasive plants is critical for developing effective management and control strategies."Figuring out why invasive species are able to proliferate so readily in new areas is one of the most important issues in ecology and nature protection," concludes Wróbel, "and the results of our research provide additional insight into the factors responsible for the success of certain non-native species."
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New Species
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July 23, 2019
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https://www.sciencedaily.com/releases/2019/07/190723104059.htm
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The first bioluminescent click beetle discovered in Asia represents a new subfamily
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A remarkable bioluminescent click beetle was discovered in the subtropical evergreen broadleaf forests in southwest China. Scientists Mr. Wen-Xuan Bi, Dr. Jin-Wu He, Dr. Xue-Yan Li, all affiliated with the Chinese Academy of Sciences (Kunming), Mr. Chang-Chin Chen of Tianjin New Wei San Industrial Company, Ltd. (Tianjing, China) and Dr. Robin Kundrata of Palacký University (Olomouc, Czech Republic) published their findings in the open-access journal
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Even though the family of click beetles ("In 2017, during an expedition to the western Yunnan in China, we discovered a dusk-active bioluminescent click beetle with a single luminous organ on the abdomen, " recalls lead scientist Mr. Wen-Xuan Bi.Since no bioluminescent click beetle had previously been recorded in Asia, the team conducted simultaneous morphological and molecular analyses in order to clarify the identity of the new species and figure out its relationship to other representatives of its group.Co-author Dr. Xue-Yan Li explains: "The morphological investigation in combination with the molecular analysis based on 16 genes showed that our taxon is not only a new species in a new genus, but that it also represents a completely new subfamily of click beetles. We chose the name Sinopyrophorus for the new genus, and the new subfamily is called In conclusion, the discovery of the new species sheds new light on the geographic distribution and evolution of luminescent click beetles. The authors agree that as a representative of a unique lineage, which is only distantly related to the already known bioluminescent click beetles, the new insect group may serve as a new model in the research of bioluminescence within the whole order of beetles.
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New Species
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July 22, 2019
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https://www.sciencedaily.com/releases/2019/07/190722182134.htm
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A toxic chemical in marine ecosystems turns out to play a beneficial role
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Advocates of healthy eating often extol the benefits of adding antioxidants to one's diet. These compounds are thought to suppress "free radical" molecules in the body that can age cells as a response to stress.
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These destructive free radicals -- known as reactive oxygen species -- also exist in marine ecosystems and are thought to degrade the cells of phytoplankton and other organisms. A new paper, however, suggests that these molecules actually play a beneficial role, upending some conventional wisdom.Julia Diaz, a newly hired marine biogeochemist at Scripps Institution of Oceanography at the University of California San Diego, and colleagues report that the reactive oxygen species produced by one type of phytoplankton, the diatom Thalassiosira oceanica, protects cells from overproduction of a compound that is used to power photosynthesis. In essence, that reactive oxygen species acts to protect cells' batteries from the effects of overcharging.The study, "NADPH-dependent extracellular superoxide production is vital to photophysiology in the marine diatom Thalassiosira oceanica," appears July 22 in the journal "Our findings point to a new role for reactive oxygen species in the photosynthetic health of this diatom. The next challenge is to determine whether this process also exists in other phytoplankton species," said Diaz.The findings could have implications for marine organisms and their chemical environment. The type of reactive oxygen species studied by Diaz is known as superoxide, which is a charged oxygen atom. Superoxide has been identified as a probable culprit in die-offs of fish and marine animals when toxic algae blooms spread in the ocean, suggesting a need for scientists to better understand how and why it is produced in certain circumstances. The varying positive and negative roles of superoxide could be a critical factor in how marine ecosystems respond to climate change. It is possible, Diaz said, that superoxide production could mitigate stress, which is a form of ocean resilience to changing climate that has not been understood previously.Superoxide is present throughout ocean ecosystems but how it is used by diatoms like T. oceanica had been a mystery. They need sunlight and carbon to conduct photosynthesis and have a variety of ways to perform the task to adapt to either low or intense-light conditions. A compound they make called NADPH is the power source that lets them take up and "fix" carbon into carbohydrates. Very bright light can cause diatoms to overproduce NADPH.After studying superoxide production in diatoms at various light levels, Diaz and colleagues concluded that, akin to a surge protector, making superoxide protects cells at times when too much NADPH is produced and restores balance to keep photosynthesis at peak efficiency.Diaz, who joined the Scripps faculty as an assistant professor this month, performed this research as a postdoctoral scholar at Woods Hole Oceanographic Institution in Woods Hole, Mass., and as an assistant professor at the University of Georgia Skidaway Institute of Oceanography. Sydney Plummer, who also contributed to the study, will continue this research as Diaz's student in the Scripps PhD program beginning this fall.Other co-authors on the paper include Colleen Hansel, Mak Saito, and Matthew McIlvin of Woods Hole Oceanographic Institution as well as Peter Andeer of Lawrence Berkeley National Lab. The Ford Foundation, the National Science Foundation, and the University of Georgia Research Foundation funded the work.
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New Species
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July 21, 2019
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https://www.sciencedaily.com/releases/2019/07/190721085851.htm
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New species of pocket shark identified
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A team of researchers, including two from Tulane University, has identified a new species of pocket shark, following careful study of a pocket shark that made international headlines in 2015 after it was brought to the Royal D. Suttkus Fish Collection at the Tulane University Biodiversity Research Institute.
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The 5½-inch male kitefin shark has been identified as the American Pocket Shark, or The details of the new species, which was caught in the Gulf of Mexico in February 2010, are described in an article published in the animal taxonomy journal "In the history of fisheries science, only two pocket sharks have ever been captured or reported," Grace said. "Both are separate species, each from separate oceans. Both are exceedingly rare."Bart added, "The fact that only one pocket shark has ever been reported from the Gulf of Mexico, and that it is a new species, underscores how little we know about the Gulf -- especially its deeper waters -- and how many additional new species from these waters await discovery."Researchers said there were notable differences between the original Pacific Ocean specimen and the newer specimen from the Gulf of Mexico. Those differences include fewer vertebrae and numerous light-producing photophores that cover much of the body. The two species both have two small pockets that produce luminous fluid (one on each side near the gills).The pocket shark was collected in February 2010 in the eastern Gulf of Mexico by the NOAA ship Identifying the shark involved examining and photographing external features of the specimen with a dissecting microscope, studying radiographic (x-ray) images and high resolution CT scans. The most sophisticated images of internal features of the shark were produced at the European Synchrotron Radiation Facility (ESRF) in Grenoble, France, which uses the most intense source of synchrotron-generated light in the world to produce x-rays 100 billion times brighter than the x-rays used in hospitals.Bart said the partnership between Tulane and NOAA was instrumental to the work that lead to the discovery and identification of the American Pocket Shark. "The Tulane-NOAA Fisheries partnership is continuing and may lead to additional discoveries in the future," he said.
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New Species
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July 19, 2019
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https://www.sciencedaily.com/releases/2019/07/190719102105.htm
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Turkestan cockroach selling online is a companion of the common household cockroach
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Many nocturnal animals including insects use a species-specific smell, that is sex a pheromone, to locate and attract potential mates. For example, female American cockroaches emit sex pheromones called "periplanones" with unique chemical structures. Males that detect them with their antennae orientate towards the pheromone source, preform courtship rituals, and mate.
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The Turkestan cockroach, Recent molecular genetic studies have shown that the Turkestan cockroach is phylogenetically close to the American cockroach in the genus This study, led by Hiroshi Nishino and published in Researchers also found that a male Turkestan cockroach was attracted to periplanone, but, unlike American cockroaches, the pheromone alone did not trigger courtship rituals. Courtship rituals started only after coming in contact with a female of the same species. This implies that a low volatile substance on the female's body plays an important role in preventing the species from mating with other species."Turkestan cockroaches adapt to inground containers where odor molecules diffuse very slowly and this could be why they have evolved an enlarged glomerulus to detect tiny packets of pheromones," says Hiroshi Nishino. He added, "We need exercise caution when handling Turkestan cockroaches because they are a member of the genus
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New Species
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July 15, 2019
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https://www.sciencedaily.com/releases/2019/07/190715075436.htm
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Tiny habitant from Abrolhos bank (Brazil) sheds light on tropical Atlantic biogeography
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For the first time, the bivalve mollusc Guyanella clenchi has been reported from Abrolhos Bank, Brazil. This almost unknown bivalve had previously been reported solely from the Caribbean region. Apart from being the southernmost record for the species, its presence also helps the experts to determine the way the marine fauna from the Caribbean interacts with its South American relatives.
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The bivalve, which is a minute mollusc of only a few millimetres, had been known from Suriname, Guadeloupe, Colombia and French Guiana for nearly half a century. However, it is almost absent from the bibliographical registers and zoological collections.Then, unexpectedly, during recent cruises to Abrolhos Bank (Bahia, Brazil), carried out as part of the Pro-Abrolhos project at Instituto Oceanografico da Universidade de Sao Paulo (IO-USP), enough specimens were retrieved to document the mysterious species from the Brazilian site.The resulting study is published in the open-access journal According to the scientists, the discovery is very important for the understanding of the interaction between the mollusc faunas from the Caribbean and Southern Atlantic regions. While a mixture of these had long been known at both localities, serving as evidence that many species are indeed capable of crossing the geographical barriers between the two oceanic areas, it seems that no one had managed to answer how exactly this is happening. Now, the discovery of the tiny species shows that even small-sized molluscs have the ability to disperse so widely.Additionally, the discovery of fresh specimens, complete with the body inside the shell, brings to light new information about the anatomy of the species itself, since the existing knowledge had only been derived from dry shells. Now, the secretive bivalve is to finally undergo molecular analyses."Despite its small size, the new occurrence of Guyanella clenchi brings new key data needed to understand the biogeography of the Caribbean and Southern Atlantic regions and improve our knowledge of the molluscs inhabiting the Brazilian coast, specifically the Abrolhos Bank, which is an important South Atlantic biodiversity hotspot," explain the researchers behind the study.Abrolhos Bank is the largest and most species-rich coral reef in the Southern Atlantic. It is located in the Abrolhos Archipelago area and is part of the Abrolhos Marine National Park. Its most notable peculiarity is the giant coral structures shaped like mushrooms, locally known as "Chapeiroes." A "chapeirao" can reach up to 25 metres in height and 50 metres in diameter. The region is considered the most biodiverse spot in the Southern Atlantic Ocean, providing home to several species that occur nowhere else.
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New Species
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July 12, 2019
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https://www.sciencedaily.com/releases/2019/07/190712133336.htm
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Hear them roar: How humans and chickadees understand each other
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Is there something universal about the sounds we make that allows vocal learners -- like songbirds -- to figure out how we're feeling? Sounds like it, according to new research by University of Alberta scientists.
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The researchers examined the elements within vocalizations that indicate a level of arousal such as fear or excitement. They found that both humans and black-capped chickadees can detect arousal levels in other species."The idea is that some species can understand other species' vocalizations," explained Jenna Congdon, PhD student in the Department of Psychology. "For instance, a songbird is able to understand the call of distress of a different type of songbird when they are in the presence of a predator, like an owl or a hawk. Or, for example, if your friend scared you and you screamed. Both of these are high-arousal vocalizations, and being able to understand what that sounds like in a different species can be very useful."Under the supervision of Professor Chris Sturdy, Congdon conducted two experiments, one examining chickadees and another examining humans. In the experiments, participants distinguished between high- and low-arousal vocalizations produced by other species, including alligators, chickadees, elephants, humans, pandas, piglets, ravens, macaques, and tree frogs. Human subjects were able to identify high arousal in different species."Black-capped chickadees were also able to identify high arousal in other chickadees, humans, and giant pandas," said Congdon. "This is fascinating, because a chickadee that has never come across a giant panda before is able to categorize high -- and low -- arousal vocalizations."The scientists suspect that other vocal learners, or species that learn their vocalizations from parents and models in order to survive, have this ability as well. "It is only a small group of species who do this in the world -- humans, songbirds, hummingbirds, parrots, bats, whales and dolphins, and elephants," said Congdon. "If humans and songbirds show an innate ability to understand the vocalizations of other species, would other vocal learners show this same propensity?"
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New Species
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July 3, 2019
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https://www.sciencedaily.com/releases/2019/07/190703121417.htm
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Two new species of parasitic wasps described from an altitude of over 3,400 m in Tibet
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Specimens kept in the collection of the Institute of Beneficial Insects at the Fujian Agriculture and Forestry University (FAFU, China) revealed the existence of two previously unknown species of endoparasitoid wasps. Originally collected in 2013, the insects are known to inhabit prairies and bushes at above 3,400 m, which is quite an unusual altitude for this group of wasps.
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The new to science wasps are described and illustrated in a paper published in the open-access, peer-reviewed scholarly journal Looking very similar to each other, the species were found to belong to one and the same genus (Microplitis), which, however, is clearly distinct from any other within the subfamily, called Microgastrinae. The latter group comprises tiny, mostly black or brown wasps that develop in the larvae of specific moths or butterflies. Interestingly, once parasitised, the host continues living and does not even terminate its own growth. It is only killed when the wasp eggs hatch and feed on its organs and body fluids before spinning cocoons.From now on, the newly described wasps will be called by the scientific names Microplitis paizhensis and Microplitis bomiensis, where their species names refer to the localities from where they were originally collected: Paizhen town and Bomi county, respectively.Due to their parasitism, some microgastrine wasps are considered important pest biocontrol agents. Unfortunately, the hosts of the newly described species remain unknown.In addition, the scientists also mention a third new to science species spotted amongst the specimens they studied. However, so far they have only found its male, whereas a reliable description of a new microgastrine wasp requires the presence of a female.
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New Species
| 2,019 |
July 2, 2019
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https://www.sciencedaily.com/releases/2019/07/190702112836.htm
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Trendy on eight legs: Jumping spider named after fashion czar Karl Lagerfeld
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New to science species of Australian jumping spider was named after Hamburg-born fashion icon Karl Lagerfeld (1933-2019) after the arachnid reminded its discoverers of the designer. Intrigued by its distinct 'downplayed' black-and-white colours, the Hamburg-Brisbane-Melbourne team likened the spider's appearance to Lagerfeld's trademark style: his white hair and Kent collar that contrasted with the black sunglasses and gloves.
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Thus, the curious species, now officially listed under the name Jotus karllagerfeldiI was described in the open-access journal When compared with other members in the 'brushed' jumping spider genus Jotus, the novel species clearly stands out due to its black-and-white legs and tactile organs (pedipalps), whereas the typical representative of this group demonstrates striking red or blue colours."The animal reminded us with its colours of the reduced style of Karl Lagerfeld. For example, we associate the black leg links with the gloves he always wore," Danilo Harms explains.In fact, what was to be now commonly referred to as Karl Lagerfeld's Jumping Spider was identified amongst specimens in the Godeffroy Collection. Kept at CeNak, the historical collection was originally compiled by the inquisitive and wealthy tradesman from Hamburg Johann Cesar Godeffroy, who financed several expeditions to Australia back in the 19th century. Here, the research team identified another link between Australia, Godeffroy, Hamburg and Jotus karllagerfeldi.Besides the tiny (4 to 5 mm) arachnid, whose pedipalps resemble a white Kent collar, the scientists describe another seven new to science species and add them to the same genus. Two of those, Jotus fortiniae and Jotus newtoni, were also named after inspirational figures for their hard work and creativity: educator, molecular biologist and science communicator Dr Ellen Fortini (Perth College, Western Australia) and keen naturalist and photographer Mark Newton. All novel species were found either in the Godeffroy Collection or amongst the jumping spiders housed at Queensland Museum.Surprisingly, even though the genus Jotus comprises numerous species found all over Australia, there is not much known about these spiders. An interesting feature, according to the scientists behind the present study, are the huge telescopic eyes, which allow for spatial vision. The Jotus species need this ability in foraging, since they do not weave webs, but rather hunt in the open. Thus, they have evolved into extremely fast and agile hunters, capable of jumping short distances.Curiously, back in 2017, the team of Barbara and Danilo, joined by Dr Robert Raven from Queensland Museum, described another previously unknown, yet fascinating species: a water-adapted spider, whose sudden emergence at the coastline of Australia's "Sunshine State" of Queensland during low tide in January brought up the association with reggae legend Bob Marley and his song "High Tide or Low Tide." The species, scientifically known as Desis bobmarleyi, was also published in
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New Species
| 2,019 |
June 26, 2019
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https://www.sciencedaily.com/releases/2019/06/190626200313.htm
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Bird three times larger than ostrich discovered in Crimean cave
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A surprise discovery in a Crimean cave suggests that early Europeans lived alongside some of the largest ever known birds, according to new research published in the
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It was previously thought that such gigantism in birds only ever existed on the islands of Madagascar and New Zealand as well as Australia. The newly-discovered specimen, discovered in the Taurida Cave on the northern coast of the Black Sea, suggests a bird as giant as the Madagascan elephant bird or New Zealand moa. It may have been a source of meat, bones, feathers and eggshell for early humans."When I first felt the weight of the bird whose thigh bone I was holding in my hand, I thought it must be a Malagasy elephant bird fossil because no birds of this size have ever been reported from Europe. However, the structure of the bone unexpectedly told a different story," says lead author Dr Nikita Zelenkov from the Russian Academy of Sciences."We don't have enough data yet to say whether it was most closely related to ostriches or to other birds, but we estimate it weighed about 450kg. This formidable weight is nearly double the largest moa, three times the largest living bird, the common ostrich, and nearly as much as an adult polar bear."It is the first time a bird of such size has been reported from anywhere in the northern hemisphere. Although the species was previously known, no one ever tried to calculate the size of this animal. The flightless bird, attributed to the species Pachystruthio dmanisensis, was probably at least 3.5 metres tall and would have towered above early humans. It may have been flightless but it was also fast.While elephant birds were hampered by their great size when it came to speed, the femur of the current bird was relatively long and slim, suggesting it was a better runner. The femur is comparable to modern ostriches as well as smaller species of moa and terror birds. Speed may have been essential to the bird's survival. Alongside its bones, palaeontologists found fossils of highly-specialised, massive carnivores from the Ice Age. They included giant cheetah, giant hyenas and sabre-toothed cats, which were able to prey on mammoths.Other fossils discovered alongside the specimen, such as bison, help date it to 1.5 to 2 million years ago. A similar range of fossils was discovered at an archaeological site in the town of Dmanisi in Georgia, the oldest hominin site outside Africa. Although previously neglected by science, this suggests the giant bird may have been typical of the animals found at the time when the first hominins arrived in Europe. The authors suggest it reached the Black Sea region via the Southern Caucasus and Turkey.The body mass of the bird was reconstructed using calculations from several formulae, based on measurements from the femur bone. Applying these formulae, the body mass of the bird was estimated to be around 450kg. Such gigantism may have originally evolved in response to the environment, which was increasingly arid as the Pleistocene epoch approached. Animals with a larger body mass have lower metabolic demands and can therefore make use of less nutritious food growing in open steppes."The Taurida cave network was only discovered last summer when a new motorway was being built. Last year, mammoth remains were unearthed and there may be much more to that the site will teach us about Europe's distant past," says Zelenkov.
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New Species
| 2,019 |
June 24, 2019
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https://www.sciencedaily.com/releases/2019/06/190624111534.htm
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Additions, deletions, and changes to the official list of North American birds
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The latest supplement to the American Ornithological Society's checklist of North and Middle American birds is being published in
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Birdwatchers eager to build their "life lists" will be especially interested in the five species added to the checklist due to "splits," where scientists have determined that bird populations once believed to be part of the same species are actually distinct; these newly-recognized species include the Choco Screech-Owl, Socorro Parakeet, and Stejneger's Scoter. Eight species from Eurasia and South America have also been added to the list as a result of recent sightings in North America, and one species familiar to parrot fanciers, the Budgerigar, was removed from the list. Native to Australia, escaped pet "budgies" established a wild breeding population in central Florida in the 1950s. However, the population had been declining for decades, and as of 2014, Florida's budgies have died out, possibly due to competition for nest sites from other non-native birds.More than just a list that species are added to and deleted from, however, the checklist is also the authority on how North America's bird species are sorted into genera and families based on their evolutionary relationships. This year, new genetic data led to the rearrangement of several of these groups. A genus of Neotropical tanagers called Tangara was split up, and a group of seabirds known as storm-petrels that were previously classified into two genera have now been lumped into a single genus called Hydrobates. AOS's North American Classification Committee, the group of scientists responsible for the checklist, also made several tweaks to the names and classifications of hummingbird species, including taking the step of changing the official English name of one species that occurs in the southwestern U.S. and Mexico from "Blue-throated Hummingbird" to "Blue-throated Mountain-gem.""There are seven hummingbird species in the genus Lampornis, and all but two of them already had the common name 'mountain-gem,'" explains committee chair Terry Chesser, USGS Research Zoologist at the Patuxent Wildlife Research Center. "Usually we don't like to change the English names just to make them 'better,' because you could go through and make practically any bird name better if you wanted to, but in this case we thought it was worthwhile. We hope that calling all the birds in that genus by the name 'mountain-gem' will help birders understand a little bit more about the birds they're looking at, both in terms of associating these seven species with each other and in recognizing them as distinct from species in other genera simply called 'hummingbird.'"
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New Species
| 2,019 |
June 19, 2019
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https://www.sciencedaily.com/releases/2019/06/190619142551.htm
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New species of rock-eating shipworm identified in freshwater river in the Philippines
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A newly identified genus and species of worm-like, freshwater clam, commonly known as a shipworm, eats rock and expels sand as scat while it burrows like an ecosystem engineer in the Abatan River in the Philippines.
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Local residents of Bohol Island tipped off an international group of scientists, including University of Amherst post-doctoral researcher Reuben Shipway, to the watery location of the bivalve, which the scientists named "These animals are among the most important in the river and in this ecosystem," says Shipway, a marine biologist working in the microbiology lab of professor Barry Goodell and lead author of the paper that describes Co-authors include Marvin Altamia and Daniel Distel of Ocean Genome Legacy Center at Northeastern University, where Shipway previously worked; Gary Rosenberg of Drexel University; Gisela Concepcion of the University of the Philippines; and Margo Haygood of the University of Utah."Most other shipworms are as skinny as your finger," Shipway says. "These animals are quite chubby, robust. They look really different. Where they get their nutrition we don't know."It's the second new genus and species of shipworm recently discovered in the Philippines by this international team of researchers known as the Philippine Mollusk Symbiont International Collaborative Biodiversity Group, funded by the National Institutes of Health. The other new bivalve, the impossibly elongated, pink and pinstriped Tamilokus mabinia, eats wood like most shipworms and was found to be filled with bacteria that provide its nutrition. The team of scientists produced a video abstract detailing its identification.The researchers analyzed The new shipworm also may provide new insights for paleontologists. Until recently, fossil borings in rocky substrates were thought to be a marker for ancient marine habitats, Shipway explains. Shipway says the international collaborative aims to understand and preserve biodiversity, boost research capabilities of partners in the Philippines and, most importantly, use the biodiversity the animals reflect for new drug discovery.He concludes, "This is one of the most noble projects I've ever been involved in."
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New Species
| 2,019 |
June 18, 2019
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https://www.sciencedaily.com/releases/2019/06/190618123515.htm
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Monitoring biodiversity with sound: How machines can enrich our knowledge
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For a long time, ecologists have relied on their senses when it comes to recording animal populations and species diversity. However, modern programmable sound recording devices are now the better option for logging animal vocalisations. Scientists lead by the University of Göttingen have investigated this using studies of birds as an example. The results were published in the journal
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"Data collection by people is less reliable, provides only approximate values, and is difficult to standardise and verify," says first author Dr Kevin Darras from the Department of Crop Sciences at the University of Göttingen. For comparison purposes, the international research team prepared a systematic overview based on data from previous bird studies. In addition to the collected sound recordings, they also compared the usefulness of both methods.The result: sound recording devices can provide the same data as those obtained by people during bird "point counts" (the standard survey method where a person logs the birds they see or hear). Sound recordings can be used to measure population densities and map territories of individual species. They can also record entire soundscapes and better measure animal activity over long periods of time. "In a previous meta-analysis, we found that recording devices could detect and identify at least as many species as traditional ornithologists using standard techniques," says Darras. There are further advantages: enormous amounts of data can be checked, archived and automatically evaluated by computer programs to identify animal species."There are now very inexpensive, small devices that can record huge amounts of data over long periods of time and large spaces. In an increasingly data-driven time, they are the better choice." In addition to the systematic comparison, the study also provides a guide for scientists who sample the noises of animal populations acoustically. The authors give an overview of the currently available recording devices and discuss their modes of operation.
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New Species
| 2,019 |
June 18, 2019
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https://www.sciencedaily.com/releases/2019/06/190618113130.htm
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Scientists challenge notion of binary sexuality with naming of new plant species
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A collaborative team of scientists from the US and Australia has named a new plant species from the remote Outback. Bucknell University biology postdoctoral fellow Angela McDonnell and professor Chris Martine led the description of the plant that had confounded field biologists for decades because of the unusual fluidity of its flower form. The discovery, published in the open access journal
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The new species of bush tomato discovered in remote Australia provides a compelling example of the fact that sexuality among Earth's living creatures is far more diverse -- and interesting -- than many people likely realize.Bucknell University postdoctoral fellow Angela McDonnell and biology professor Chris Martine led the study following an expedition last year to relocate populations of the new plant, which were first noted by Australian botanists during the 1970s.Herbarium specimens from those few earlier collections are peppered with notes regarding the challenge of identifying the sexual condition of this plant, which appeared at various times to be female, male, or bisexual.According to Martine, about 85% of the planet's quarter-million flowering plant species have flowers that are bisexual -- with both male and female organs present in every blossom."So that's already quite different than what some people might expect; but the remaining 15% or so come in all sorts of forms that push the envelope further, including unisexual flowers and (like we see in a plant like Cannabis) whole plants that are either male or female.""For the most part, a given plant species will stick to one primary and predictable type of sexual expression," said Martine "but what makes Solanum plastisexum stand out is that it is one of a just a few plants that kind of do it all. It really seems like you never know what you'll get when you come across it."When DNA studies in Martine's lab offered proof that these plants were not only all the same thing, but a species not yet described, he, McDonnell, Jason Cantley (San Francisco State University), and Peter Jobson (Northern Territory Herbarium in Alice Springs) set out to hunt for populations along the unpaved Buchanan Highway in the remote northwestern region of the Northern Territory.The botanists were able to collect numerous new specimens and have now published the new species description in the open-access journal "This name, for us, is not just a reflection of the diversity of sexual forms seen in this species," wrote the authors in the article. "It is also a recognition that this plant is a model for the sort of sexual fluidity that is present across the Plant Kingdom -- where just about any sort of reproductive form one can imagine (within the constraints of plant development) is present."Also known as the Dungowan bush tomato, The scientists hope that the naming of this latest new species turns a spotlight on the fact that nature is full of examples for the myriad ways in which living things behave sexually."In a way, "When considering the scope of life on Earth," the authors conclude, "The notion of a constant sexual binary consisting of two distinct and disconnected forms is, fundamentally, a fallacy."Bucknell sophomore Heather Wetreich, who measured and analyzed the physical characters of the new species using plants grown from seed in a campus greenhouse, joins McDonnell, Cantley, Jobson, and Martine as a co-author on the publication.
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New Species
| 2,019 |
June 6, 2019
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https://www.sciencedaily.com/releases/2019/06/190606101811.htm
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Two new species of 'tweezer-beaked hopping rats' discovered in Philippines
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Just about everybody loves peanut butter. We put it on sandwiches and in candy, we use it to trick our dogs into taking their heartworm pills, and, when we have to, we bait mouse traps with it. But, as scientists learned when trapping rodents in the mountains of the Philippines, peanut butter isn't for everyone. A highly distinctive (weird-looking) group of rodents sometimes called "tweezer-beaked hopping rats" don't care for peanut butter, but love earthworms. Armed with this knowledge (and worms), the scientists discovered two new species of the tweezer-beaked hopping rats. The discovery was announced in the
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"In the late 1980s we were doing standard mammalogy surveys and using standard baits that most rodents really like: a combination of peanut butter and slices of fried coconut. It was really attractive bait, it makes your mouth water," says lead author Eric Rickart, a curator of the Natural History Museum of Utah at the University of Utah. The researchers knew that some of these critters had been found in the area before, but the rats weren't biting. One finally stumbled into a live trap, but it still didn't touch the peanut butter bait. The team tried to figure out what it did eat; when they offered it an earthworm, the rat, in Rickart's words, "slurped it up like a kid eating spaghetti.""Once we began baiting the traps with live, wriggling earthworms, we discovered that these little animals are common and widespread," says Larry Heaney, a curator at the Field Museum and a co-author of the study. The field team, led by the late Danny Balete of the Field Museum, began finding more species that specialize in eating earthworms, including the two new species described in their recent paper.The new species are named "They're quite bizarre," says Rickart. "They hop around on their sturdy hind legs and large hind feet, almost like little kangaroos. They have long, delicate snouts, and almost no chewing teeth.""They're very docile, very cute," adds Heaney. "Their fur is short and very, very dense, like a plush toy. They make little runways through the forest and patrol these little trails, day and night, looking for earthworms."The two new rodents are examples of the generally poorly-known, incredible biodiversity of the Philippines, which boasts more unique species of mammals per square mile than anywhere else on Earth. "Up until the late '90s, we all thought maximum mammalian diversity was in the lowland tropical rainforest" explains Heaney. But Heaney, Rickart, and their colleagues found that mountains like those on the Philippines were the perfect breeding ground for new species of mammals. The different habitats at different elevations on a mountain can lead to different adaptations by its mammal residents, and their diversity actually increases as you go up higher into the mountains. Furthermore, the mammals on one mountain are isolated from their relatives on other mountains. Generations of isolation eventually lead to new species forming on different mountains, the same way that unique species emerge on islands. "Just about every time we've gone to a new area of Luzon with mountains, we've discovered that there are unique species," says Rickart.But the Philippines' biodiversity is under threat. The islands are among the most extensively deforested places on Earth, with only about 6% of the original old growth tropical forest remaining. That's a big problem for the watershed. High mountains in the Philippines receive between 10 and 20 feet of rain every year, leaving steep slopes vulnerable to typhoons. The mulch-carpeted mossy forests in the mountains help to soak up that rain "like a giant sponge," says Heaney. "If you don't have an intact watershed and forest up in the mountains, you're going to have massive floods and landslides, because the water floods off instead of getting absorbed into mossy ground cover."The researchers hope that the discovery of the two new species of tweezer-beaked hopping rats will serve as an argument for protecting the mountainous forests where they're found. "Every time we find a reason to say, 'This place is unique,' that tells people that it's worthy of protection," says co-author Phillip Alviola of the University of the Philippines.All of the work on this project was conducted with permits and strong support of the Philippine Department of Natural Resources. The study was contributed to by authors from the University of Utah/Utah Natural History Museum, the Field Museum, the University of Kansas, the University of the Philippines, and Louisiana State University.
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New Species
| 2,019 |
June 5, 2019
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https://www.sciencedaily.com/releases/2019/06/190605100328.htm
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Working landscapes can support diverse bird species
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Privately-owned, fragmented forests in Costa Rica can support as many vulnerable bird species as can nearby nature reserves, according to a study from the University of California, Davis.
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The research suggests that working with landowners to conserve or restore forests on working landscapes can help protect wildlife. In Costa Rica, working landscapes include forest patches, crops, pastures and small towns.The study, published June 5 in the Such information is being used by local conservation organizations to help prioritize sites for rainforest restoration across the study region."With sufficient forest cover, working landscapes -- even if degraded and fragmented -- can maintain bird communities that are indistinguishable from those found in protected areas," said lead author Daniel Karp, an assistant professor in the UC Davis Department of Wildlife, Fish and Conservation Biology. "This means that private landowners have great power to improve the conservation value of their lands through reforestation."As part of a research project funded by National Geographic, the authors surveyed Neotropical birds at 150 sites across northwestern Costa Rica over two years. They found that agricultural fields hosted diverse bird communities, but those birds were distinct from species found in protected areas. Agricultural species also had large distributions, making them of lower conservation value than species found in protected areas.Privately-owned forests, however, housed the same bird species as those found in protected areas, despite being twice as fragmented and more degraded by logging, hunting and fires. This effect was especially strong in wetter and more forested areas. For instance, reforesting the wettest sites would increase bird similarity to protected areas four-fold compared to a two-fold increase in the driest sites, the study reported.After decades of decline, forest coverage in Costa Rica has been increasing since around the early 1990s. That is when the country began providing monetary incentives for landowners to maintain forest on their private lands.In a related study published May 20 in the journal "Tropical birds respond very strongly to the amount of forest in their immediate vicinity," Karp said. "That's encouraging because it means forest restoration on a small scale, even in small patches, can be really effective in safeguarding vulnerable bird species."
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New Species
| 2,019 |
June 4, 2019
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https://www.sciencedaily.com/releases/2019/06/190604172648.htm
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Scientists crack origin of the Persian walnut
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Prized worldwide for its high-quality wood and rich flavor of delicious nuts, the Persian walnut (
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China leads world production, followed by California, Turkey and Iran. But until now, the evolution of walnuts has been unknown. Walnuts have a rich fossil record, which suggest an origin of walnuts and initial divergence into black walnuts and butternuts (white walnuts) in North America, some 35-45 million years ago. With this high age, both walnut lineages would have had ample opportunity to migrate into the Old World via the Bering and North Atlantic land bridges, yet only butternuts have been detected in the fossil records of Europe and Asia, and no ancient fossils of the Persian walnut are known.Using genomic data analyzed with phylogenetic and population genetic approaches, researchers have now cracked this mystery, showing that the Persian walnut is the result of hybridization between two long-extinct species around 3.45 million years ago.Past analyses by the team based on some 2900 single-copy nuclear genes from 19 species of walnuts were unable to sort out the relationships between North American, Asian, and Persian walnut species. However, they excluded incomplete lineage sorting as the cause of the phylogenetic uncertainty. "This led us to speculate that ancient hybridization might be involved in the origin of the Persian walnut and the American butternut," said Da-Yong Zhang, a population geneticist who is one of the senior authors.To test their hybridization hypothesis, rather than look at individual genes, this time, they used whole-genome sequencing from 80 individual trees that represented 19 of the 22 species of "We applied a battery of genome-wide methods for hybridization detection and to test speciation models to infer the time of origin of the Persian walnut," said the Wei-Ning Bai, another senior author. "In the end, we characterized the genetic composition of the genomes of not only the Persian walnut, but also the Iron walnut, "All of our genome-wide analyses converged to provide unambiguous evidence of hybridization at the roots of both the American butternut ("The genomic mosaicism of both the Persian walnut (incl.
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New Species
| 2,019 |
June 4, 2019
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https://www.sciencedaily.com/releases/2019/06/190604084853.htm
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Fear of 'killer shrimp' could pose major threat to European rivers
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The fear of invasive 'killer shrimp' can intimidate native organisms to such a degree that they are incapable of performing their vital role in river systems, a new study suggests.
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Writing in the journal This is having major localised effects since the voracious predator consumes a vast range of species, with its behaviour subsequently being linked to ecosystem changes and even local extinctions.The new study shows for the first time that the mere presence of the predator -- a so-called non-consumptive effect (NCE) -- can reduce the normal effectiveness of its prey.It leads to them expending more energy in simply avoiding the predator in a bid for self-preservation, rather than focussing on core ecosystem tasks such as shredding fallen leaf litter into smaller particles to be consumed by other species.The research was conducted by independent consultant Dr Calum MacNeil and Mark Briffa, Professor of Animal Behaviour at the University of Plymouth.For the study, one of three different Gammarus species (all commonly found in European rivers) were placed inside a tank. In half of the tanks, a sample of the The behaviour of the Gammarus were then assessed over the space of several days, with researchers measuring to what extent they shredded leaves as they would be expected to do in their natural environment.The results showed that after four days, each Gammarus species showed lower shredding efficiency in the presence of the caged 'killer shrimp' compared to the treatments where it was absent.Dr MacNeil, who has spent more than 20 years studying the species in this study, said: "This study demonstrates an unappreciated and indirect impact of a biological invasion by a voracious predator. It shows that the mere presence of an invader can influence resident prey behaviour, in this case the feeding efficiency of naïve residents. The Gammarus in our experiment had no prior exposure to its predatory rival, and would not have known to respond to specific alarm cues. However, none of our samples showed any evidence of habituation during the course of the experiment -- in fact quite the opposite."Professor Briffa, whose research has previously included assessments of fighting within species such as hermit crabs and sea anemones, added: "Our results indicate that the effect of NCEs on functionally important species may have ramifications, for example, impacting the recovery of stream communities following perturbation. A better understanding of the role of NCEs during biological invasions could enhance our ability to predict their progress and, in some cases, the wider ecosystem level ramifications."
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New Species
| 2,019 |
May 28, 2019
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https://www.sciencedaily.com/releases/2019/05/190528120339.htm
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New snake species in Europe named after a long-forgotten Iron Age kingdom
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An international team of scientists identified the snake and its range, which includes Turkey, Azerbaijan, Armenia, Georgia, Iraq, Iran, and Russia including a small region extending into the corner of Europe. Based on the genetic and morphological data, the researchers were able to say that the Blotched Rat Snake (
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The kingdom, forgotten for over a thousand years, flourished between the 9th and 6th centuries BCE in the region of today's Armenian Highlands, centered around Lake Van in Turkey, where this new snake species occurs. The name was chosen out of respect for the original scientific name of the Blotched Rat Snake proposed by the famous Prussian natural historian of the 19th century, Peter Simon Pallas.The name The new snake species is a member of large-bodied snakes of an iconic genus
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New Species
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May 23, 2019
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https://www.sciencedaily.com/releases/2019/05/190523142207.htm
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Evolution and diversity of Leptospira bacteria
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Leptospirosis is an emerging zoonotic disease that affects more than one million people around the world each year. Researchers reporting in
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The genus Leptospira is currently divided into 35 species classified into three phylogenetic clusters that historically correlate with the level of pathogenicity of the species: saprophytic, intermediate, and pathogenic. The evolution of each of these clusters has been unclear and the virulence status of many species is unknown.In the new work, a group of researchers from the Institut Pasteur International Network (IPIN) including Mathieu Picardeau and Pascale Bourhy, of the Institut Pasteur, France, Frédéric Veyrier of the INRS-Institut Armand-Frappier, Canada, and other colleagues studied 90 Leptospira strains isolated from 18 sites across four continents, including Japan, Malaysia, New Caledonia, Algeria, France, and Mayotte. The genome of each isolate was sequenced and compared to known Leptospira genomes.Based on the genetic sequences, the team was able to identify 30 new Leptospira species. They organized the Leptospira genus, which now comprises 64 species, into four lineages or subclades, dubbed P1, P2, S1, and S2. The S2 subclade has never been described. In the P1 -- formerly known as pathogenic -- lineage, they shed light on a phenomenon of genome reworking that may explain their evolved pathogenicity."We have dusted off the Leptospira genus and gained more clarity of its diversity which will help researchers propose new standards on its classification and nomenclature. The implication of several new potentially infectious Leptospira species for human and animal health remains to be determined but our data also provide new insights into the emergence of virulence in the pathogenic species," the researchers say.
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May 17, 2019
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https://www.sciencedaily.com/releases/2019/05/190517115115.htm
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Museum volunteers discover new species of extinct heron at North Florida fossil site
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When the bones of an ancient heron were unearthed at a North Florida fossil site, the find wasn't made by researchers but by two Florida Museum of Natural History volunteers.
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A previously unknown genus and species, the heron has been named Nearly 700 volunteers have worked at the Montbrook fossil site, collectively digging more than 12,000 hours."You couldn't have a better group of people," Hodge said. "There's a lot of negativity when we get home and turn on the television, but it does you good to be out here seeing volunteers get excited and be positive about something."The bones used to identify the new heron were found by volunteers Toni-Ann Benjamin and Sharon Shears."It's invigorated the local fossil community," said David Steadman, Florida Museum curator of ornithology and lead author of the description of Because Montbrook is such an intensively worked fossil site, processing the finds takes the teamwork of scientists and amateurs. Hodge oversees much of the land management that Montbrook requires, including moving dirt and managing drainage. In addition to working outdoors at the site, volunteers prepare and catalog specimens in the Florida Museum's vertebrate paleontology lab.A good day of digging requires between 10 and 20 days to process in the lab, said Jonathan Bloch, Florida Museum curator of vertebrate paleontology and a coordinator of the fossil dig."We simply couldn't do all this work without help from the public," Bloch said. "Volunteers are not only the backbone of the dig, they're actively contributing to scientific discoveries."Steadman and then-master's student Oona Takano used the characteristics of the bird's scapula and coracoid, two bones that intersect to support the bird's shoulder, to determine the relationship between this ancient heron and modern lineages.They believe "This heron adds to this big suite of aquatic birds we're finding at Montbrook," Steadman said. "We're seeing the same families of birds you'd see around wetlands today, but they're all extinct species. The fun challenge is finding out how closely related any given species at Montbrook is to the birds that we see flying and swimming around Florida today. Even after three and a half years, we're nowhere near diminishing returns."Takano, now a University of New Mexico Ph.D. student, said that bird fossils are prized finds, particularly at a site like Montbrook where the majority of fossils belong to young gomphotheres, extinct elephant-like mammals."In general, bird bones don't fossilize well because they're hollow," she said. "It's relatively rare to find well-preserved bird bones at all and even rarer to find articulated bones," referring to bones that would have locked together in the bird's body.Most Florida fossil sites are limestone sinkholes or pitfall traps created by ancient predators to capture their prey. At Montbrook, researchers have been able to glimpse a different type of ancient environment: the riverine ecosystem. Five million years ago, Researchers believe the ancient river's current scattered decomposing animal remains, making this find of two intersecting bones even more significant. Steadman said naming the species after Hodge was a natural choice."Through the kindness of his heart and being interested -- just wanting to know what's in the ground on his land -- Eddie let us in and one thing led to another." Steadman said. "Naming this heron after Eddie is a minor part of treating him right because he's been treating us right.""He's genuinely interested in the fossils we're finding," Takano added.The Florida Museum recruits volunteers for the Montbrook dig in fall and spring and regularly encourages volunteers and students to become involved, often resulting in meaningful fossil discoveries. Finds are shared on the Florida Museum Montbrook Fossil Dig Blog."Volunteers are fascinated by this stuff -- it's really their passion," Hodge said. "There's a satisfaction in being able to provide something like this for people interested in higher learning, and you don't get the chance to do that very often. You never know what you can find. Just the next little spoonful of dirt, brush it back and there it is."
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New Species
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May 16, 2019
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https://www.sciencedaily.com/releases/2019/05/190516114607.htm
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Bedbugs evolved more than 100 million years ago
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Bedbugs -- some of the most unwanted human bed-mates -- have been parasitic companions with other species aside from humans for more than 100 million years, walking the earth at the same time as dinosaurs.
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Work by an international team of scientists, including the University of Sheffield, compared the DNA of dozens of bedbug species in order to understand the evolutionary relationships within the group as well as their relationship with humans.The team discovered that bedbugs are older than bats -- a mammal that people had previously believed to be their first host 50-60 million years ago. Bedbugs in fact evolved around 50 million years earlier.Bedbugs rank high among the list of most unwanted human bedfellows but until now, little was known about when they first originated.Experts have now discovered that the evolutionary history of bed bugs is far more complex than previously thought and the critters were actually in existence during the time of dinosaurs. More research is needed to find out what their host was at that time, although current understanding suggests it's unlikely they fed on the blood of dinosaurs. This is because bed bugs and all their relatives feed on animals that have a "home" -- such as a bird's nest, an owl's burrow, a bat's roost or a human's bed -- a mode of life that dinosaurs don't seem to have adopted.The team spent 15 years collecting samples from wild sites and museums around the world, dodging bats and buffaloes in African caves infected with Ebola and climbing cliffs to collect from bird nests in South East Asia.Professor Mike Siva-Jothy from the University of Sheffield's Department of Animal and Plant Sciences, who was part of the team, said: "To think that the pests that live in our beds today evolved more than 100 million years ago and were walking the earth side by side with dinosaurs, was a revelation. It shows that the evolutionary history of bed bugs is far more complex than we previously thought."Dr Steffen Roth from the University Museum Bergen in Norway, who led the study, added: "The first big surprise we found was that bedbugs are much older than bats, which everyone assumed to be their first host. It was also unexpected to see that evolutionary older bedbugs were already specialised on a single host type, even though we don't know what the host was at the time when The study also reveals that a new species of bedbug conquers humans about every half a million years: moreover that when bedbugs changed hosts, they didn't always become specialised on that new host and maintained the ability to jump back to their original host. This demonstrates that while some bedbugs become specialised, some remain generalists, jumping from host to host.Professor Klaus Reinhardt, a bedbug researcher from Dresden University in Germany, who co-led the study, said: "These species are the ones we can reasonably expect to be the next ones drinking our blood, and it may not even take half a million years, given that many more humans, livestock and pets that live on earth now provide lots more opportunities."The team also found that the two major bedbug pests of humans -- the common and the tropical bedbug -- are much older than humans. This contrasts with other evidence that the evolution of ancient humans caused the split of other human parasites into new species.Professor Mike Siva-Jothy from the University of Sheffield, added: "These findings will help us better understand how bedbugs evolved the traits that make them effective pests -- that will also help us find new ways of controlling them."The researchers hope the findings will help create an evolutionary history of an important group of insects, allowing us to understand how other insects become carriers of disease, how they evolve to use different hosts and how they develop novel traits. The aim is to help control insects effectively and prevent the transmission of insect-vectored disease.The research has been published in
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May 14, 2019
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https://www.sciencedaily.com/releases/2019/05/190514090043.htm
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Parents unknown: Mysterious larvae found in Panama's two oceans
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Under the microscope, sea water reveals the larval stages of little-known marine creatures called phoronids (horseshoe worms), but finding their parents is another story. Although such fanciful larvae caught the eye of scientists studying plankton -- the tiny, drifting plants and animals in the world's oceans -- as long ago as the 1800s, there are only about 15 species of phoronids known worldwide, based on adult specimens. A study of phoronid larvae published this week by scientists at the Smithsonian Tropical Research Institute (STRI) in Panama has detected eight potentially new species.
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"The global diversity of small, rare marine animals like phoronids is grossly underestimated," said STRI staff-scientist Rachel Collin. "We don't know what animals are out there, and we know even less about what their role might be in the world's oceans."Because phoronid larvae swim and drift in seawater, they are much easier to sample than their adult forms, which live on the sea floor within sands, sediment or rubble. And the larvae do not look like the adults, making it difficult to tell which larva belongs to which adult without doing a sort of paternity testing: comparing larval DNA sequences to the DNA of their potential parents.Named for the Egyptian goddess Phoronis, tubular adult horseshoe worms anchor their bodies to rocks or corals and wave a crown of ciliated tentacles to capture tiny food particles. To reproduce, their eggs and sperm unite to create embryos that hatch as swimming larvae, which then become members of the microscopic plankton. The larvae have cylindrical bodies topped with a ring of tentacles and a large hood that serves to capture food. Many are decorated with yellow pigment spots and within some it is possible to see reddish or pinkish patches of blood cells through their translucent bodies. Eventually they descend to the seafloor, develop into adults and complete their life cycle, considered the most common cycle in the animal kingdom.Scientists collected plankton from the Bay of Panama on the Pacific Coast and Bocas del Toro on the Caribbean coast. By examining plankton with a stereomicroscope, they found more than 50 phoronid larvae; 23 from the Pacific and 29 from the Atlantic. Using a genetic technique called barcoding based on DNA sequencing, they were able to distinguish three distinct phoronids in the plankton from the Bay of Panama and four others from the Caribbean.The DNA of particular genes from each of these animals was different from anything recorded in GenBank, a global collection of DNA from more than 300,000 organisms, suggesting that these larvae may belong to species that are new to science. However, finding the adults of these species may take years, especially since very few scientists study horseshoe worms."Because of the cryptic lifestyles of phoronids, the matching adult worms may never be found, yet the presence of their larval forms in plankton confirm that they are here, established and reproducing," said co-author Michael J. Boyle, previously, a Tupper postdoctoral fellow at the STRI and now a staff biologist and the principal investigator of the Life Histories Program at the Smithsonian Marine Station in Fort Pierce, Florida.At STRI's Bocas del Toro Research Station on the Caribbean, Collin, who is the station director, organizes a series of Tropical Taxonomy Training courses (
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May 9, 2019
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https://www.sciencedaily.com/releases/2019/05/190509112249.htm
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Finnish researchers discover a new moth family
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In a recently completed study, researchers of the Finnish Museum of Natural History Luomus and their collaborators have described two moth species new to science. In addition, the
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Discovering a new family of moths is comparable to researchers specialised in mammals finding entirely new species not belonging to any known mammal family, such as cats (What makes the discovery special is the fact that the species live in Eurasia, a region known relatively well in terms of its butterflies and moths. This is evidence of there being regions even on our continent with still-unknown species."It's also exceptional to describe a family on the basis of species which had never before been seen. New families are from time to time described, but such descriptions are mainly based on the reclassification of the relations between known species," says Lauri Kaila, principal author of the study and senior curator at the Finnish Museum of Natural History Luomus, which is part of the University of Helsinki.The scientific classification of organisms is based on comparative research. Today, this entails, in addition to the study of differences in structural and behavioural features, the study of differences in DNA."First, we found one undescribed species, which led to the discovery of another. Based on their structure, the species first appeared to belong to the false burnet moth family For a long time, the place of the "The recently described There are no species of the The species are well adapted to hot desert conditions. Despite the heat, at least "Most desert moth caterpillars dig into the ground for the day, resurfacing to eat plants in the night. Caterpillars of this species can be seen on plants in daytime, and they pupate in the open, instead of underground as desert species usually do. Exceptionally, the adult butterflies too are diurnal," says Kari Nupponen who observed the species in the field.The study is based on material produced by Kari Nupponen on the distribution of Asian butterflies and was carried out in cooperation with researchers from the University of Oulu and the Russian Academy of Sciences.
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May 8, 2019
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https://www.sciencedaily.com/releases/2019/05/190508142452.htm
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Statistical study finds it unlikely South African fossil species is ancestral to humans
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Statistical analysis of fossil data shows that it is unlikely that
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The research by paleontologists from the University of Chicago, published this week in The first Despite this timeline, the researchers who discovered "It is definitely possible for an ancestor's fossil to postdate a descendant's by a large amount of time," said the study's lead author Andrew Du, PhD, who will join the faculty at Colorado State University after concluding his postdoctoral research in the lab of Zeray Alemseged, PhD, the Donald M. Pritzker Professor of Organismal and Biology and Anatomy at UChicago."We thought we would take it one step further to ask how likely it is to happen, and our models show that the probability is next to zero," Du said.Du and Alemseged also reviewed the scientific literature for other hypothesized ancestor-descendant relationships between two hominin species. Of the 28 instances they found, only one first-discovered fossil of a descendant was older than its proposed ancestor, a pair of "Again, we see that it's possible for an ancestor's fossil to postdate its descendant's," Du said. "But 800,000 years is quite a long time."Alemseged and Du maintain that "Given the timing, geography and morphology, these three pieces of evidence make us think afarensisis a better candidate than sediba," Alemseged said. "One can disagree about morphology and the different features of a fossil, but the level of confidence we can put in the mathematical and statistical analyses of the chronological data in this paper makes our argument a very strong one."
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May 8, 2019
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https://www.sciencedaily.com/releases/2019/05/190508113343.htm
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Medicinal mushroom discovered in Thailand
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A species of globally recognised medicinal mushroom was recorded for the first time in Thailand. Commonly referred to as lingzhi, the fungus (
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The discoveries are published in the open-access journal Over the last centuries, the studied mushroom and its related species in the genus Ganoderma have been used extensively in traditional Asian medicines due to their natural bioactive compounds, including polysaccharides, triterpenoids, sterols, and secondary metabolites, which are used in the treatment of various diseases. Other compounds derived from lingzhi, such as the studied species, also demonstrate antimicrobial activities. The medicinal use of these mushrooms is recognised by the World Health Organization and they are featured in the Chinese Pharmacopoeia.The studied mushroom belongs to a group known to be parasitic or pathogenic on a wide range of tree species. The species is characterised with strongly laccate fruiting bodies and a cap with distinctly dark brown base colour and reddish shades. It grows to up to 7-12 cm in length, 4-8 cm in width and is up to 1.5 cm thick. While the mushroom has so far been widely reported from tropical areas, including mainland China, Taiwan and South America, it had never been recorded from Thailand.During their research, the scientists found that mycelial production for
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May 7, 2019
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https://www.sciencedaily.com/releases/2019/05/190507110436.htm
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New species of fish parasite named after Xena, the warrior princess
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A study of parasitic crustaceans attaching themselves inside the branchial cavities (the gills) of their fish hosts was recently conducted in order to reveal potentially unrecognised diversity of the genus
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While there had only been one species known from the country, a new article published in the open-access journal For one of them, the research team from North-West University (South Africa): Serita van der Wal, Prof Nico Smit and Dr Kerry Hadfield, chose the name of the fictional character Xena, the warrior princess. The reason was that the females appeared particularly tough with their characteristic elongated and ovoid bodies. Additionally, the holotype (the first specimen used for the identification and description of the previously unknown species) is an egg-carrying female.Formally recognised as To describe the new species, the scientists loaned all South African specimens identified as, or appearing to belong to the genus
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New Species
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May 7, 2019
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https://www.sciencedaily.com/releases/2019/05/190507105752.htm
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Close relatives can coexist: two flower species show us how
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Scientists have discovered how two closely-related species of Asiatic dayflower can coexist in the wild despite their competitive relationship. Through a combination of field surveys and artificial pollination experiments, the new study shows that while reproductive interference exists between the two species,
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These findings offer a different perspective on theories surrounding co-existence, and suggest a new significance for plants' ability to self-fertilize. The finding was made by Japan Society for the Promotion of Science Research Fellow Koki Katsuhara and Professor Atushi Ushimaru, both part of the Kobe University Graduate School of Human Development and Environment, and it was published on May 2 in The ability of plant species to coexist has long fascinated scientists. When species with shared pollinators flower at the same time in the same place, it's thought that the reproductive interference caused by pollinators makes it hard for these plant species to coexist. Reproductive interference occurs when pollen from another species is deposited on the pistil (female reproductive part of the flower), and competition between pollen tubes causes a decrease in seed production.The two species of Asiatic dayflower By combining fieldwork surveys with artificial pollination experiments, the team discovered that self-pollination helps to reduce the negative impact of reproductive interference. Even when one species was heavily impacted by the large number of flowers produced by the other species, through self-pollination both species managed to produce enough seeds to survive. Cc was able to produce more seeds than Ccfc through self-pollination, which is probably the cause of the asymmetrical production between the species.We would expect Cc to wipe out Ccfc through reproductive interference, but in fact both species can be found growing in the wild. Katsuhara and Ushimaru propose that the distribution of these two species plays an important role in their ability to coexist despite the strong competition between them. While most areas are dominated by Cc, in some areas Ccfc outnumbers Cc, giving it the advantage (in locations with over 70% Ccfc, it is able to leave more seeds than Cc). Even when it is almost totally surrounded by Cc, Ccfc can still leave some seeds through self-pollination.Scientists believe that self-pollination developed so that plants can still produce seeds even when pollinators are scarce. This study suggests that the self-pollination can also mitigate the negative effects when pollen from other species hinders seed production. Self-pollination could also be used to explain the coexistence of plants who share pollinators. This finding marks a step forward in shedding light on species coexistence, and gives a new perspective to the evolutionary background of self-pollination.
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New Species
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May 6, 2019
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https://www.sciencedaily.com/releases/2019/05/190506151828.htm
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Genetic adaptation to climate change
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New research led by the University of Southampton has shown that the threat of range losses for some species as a result of climate change could be overestimated because of the ability of certain animals to adapt to rising temperatures and aridity. The researchers have now developed a new approach to more accurately determine vulnerability, which could aid conservation efforts by ensuring they are focussed on species most at risk. Their findings have been published today in the scientific journal
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Current methods for assessing vulnerability ignore the potential for some animal populations to adapt genetically to their changing environment, meaning they are able to survive in warming temperatures and drier conditions better than other populations within the same species.The international team was led by Dr Orly Razgour, lecturer in Ecology at the University of Southampton, and studied the genomic data of two species of bats native to the Mediterranean, an area which is particularly affected by rising global temperatures.Dr Razgour said: "The most commonly used approach for forecasting the bats' future suggests that the range of suitable habitats for them would diminish rapidly due to climate change. However, this assumes all bats within the same species cope with changing temperatures and drier climates in the same way. We developed a new approach that takes into account the ability of bats within the same species to adapt to different climatic conditions."By taking samples from the wings of over 300 bats living in the wild, the scientists were able to study their DNA and identify the individual bats that have adapted to thrive in hot and dry conditions and those who were adapted to colder and wetter environments. They then used this information to model changes in climatic suitability and the distribution of each group under future climate change.Once the scientists had mapped the areas that were most populated by each group of adapted bats, they studied the landscapes in between each area to determine whether they would allow the hot-dry adapted bats to move to areas inhabited by the cold-wet adapted bats. The study's findings showed that there was suitable forest cover -- vital for these bats to move around -- across most of the landscapes. Thanks to this landscape connectivity, individuals adapted to hot-dry conditions can reach cold-wet adapted populations and breed with them, which will increase the potential of the population to survive as conditions become warmer and drier.Dr Razgour concluded: "We believe that if this model is used when assessing the vulnerability of any species to climate change we could reduce erroneous predictions and misplaced conservation efforts. Any conservation strategy should consider how individual animals can adapt locally and should focus not only on areas with threatened populations but also on making movement between populations easier. This is why it is important to look at the combined effect of climate change and habitat loss."
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New Species
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May 2, 2019
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https://www.sciencedaily.com/releases/2019/05/190502163028.htm
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Scientists discover evolutionary link to modern-day sea echinoderms
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Scientists at The Ohio State University have discovered a new species that lived more than 500 million years ago -- a form of ancient echinoderm that was ancestral to modern-day groups such as sea cucumbers, sea urchins, sea stars, brittle stars and crinoids. The fossil shows a crucial evolutionary step by echinoderms that parallels the most important ecological change to have taken place in marine sediments.
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The discovery, nearly 30 years in the making, was published recently in the "It throws light on a critical time, not just in the evolution of organisms, but also in the evolution of marine ecosystems," said Loren Babcock, co-author of the study and professor of earth sciences at Ohio State. "This represents a creature that clearly was making the leap from the old style of marine ecosystems in which sediments were stabilized by cyanobacterial mats, to what ultimately became the present system, with more fluidized sediment surfaces."The creature, a species of edrioasteroid echinoderm that Babcock and his researchers named Totiglobus spencensis, lived in the Cambrian Period -- about 507 million years ago. (The Earth, for the record, is about 4.5 billion years old.) A family of fossil hunters discovered the fossil in shale of Spence Gulch, in the eastern part of Idaho, in 1992, and donated it to Richard Robison, a researcher at the University of Kansas and Babcock's doctoral adviser. That part of the country is rich with fossils from the Cambrian period, Babcock said.For years, the fossil puzzled both Babcock and Robison. But the mystery was solved a few years ago, when Robison's fossil collection passed to Babcock after Robison's retirement.Once Babcock had the fossil in his lab, he and a visiting doctoral student, Rongqin Wen, removed layers of rock, exposing a small, rust-colored circle with numerous tiny plates and distinct arm-like structures, called ambulcra. Further study showed them that the animal attached itself to a small, conical shell of a mysterious, now-extinct animal called a hyolith using a basal disk -- a short, funnel-like structure composed of numerous small calcite plates.The discovery was a type of scientific poetry -- years earlier, Babcock and Robison discovered the type of shell that this animal appeared to be attached to, and named it Haplophrentis reesei.The edrioasteroid that Babcock and Wen discovered apparently lived attached to the upper side of the elongate-triangular hyolith shell, even as the hyolith was alive. They think a sudden storm buried the animals in a thick layer of mud, preserving them in their original ecological condition.Echinoderms and hyoliths first appeared during the Cambrian Period, a time in Earth's history when life exploded and the world became more biodiverse than it had ever been before. The earliest echinoderms, including the earliest edrioasteroids, lived by sticking to cyanobacterial mats -- thick, algae-like substances that covered the Earth's waters. And until the time of Totiglobus spencensis, echinoderms had not yet figured out how to attach to a hard surface."In all of Earth's history, the Cambrian is probably the most important in the evolution of both animals and marine ecosystems, because this was a time when a more modern style of ecosystem was first starting to take hold," Babcock said. "This genus of the species we discovered shows the evolutionary transition from being a 'mat-sticker' to the more advanced condition of attaching to a shelly substrate, which became a successful model for later species, including some that live today."In the early part of the Cambrian Period -- which started about 538 million years ago -- echinoderms likely lived on that algae-like substance in shallow seas that covered many areas of the planet. The algae, Babcock said, probably was not unlike the cyanobacterial mats that appear in certain lakes, including Lake Erie, each summer. But at some point, those algae-like substances became appealing food for other creatures, including prehistoric snails. During the Cambrian, as the population of snails and other herbivores exploded, the algae-like cyanobacterial mats began to disappear from shallow seas, and sediments became too physically unstable to support the animals -- including echinoderms -- that had come to rely on them.Once their algae-like homes became food for other animals, Babcock said, echinoderms either had to find new places to live or perish.Paleontologists knew that the creatures had somehow managed to survive, but until the Ohio State researchers' discovery, they hadn't seen much evidence that an echinoderm that lived this long ago had made the move from living stuck to cyanobacterial-covered sediment to living attached to hard surfaces."This evolutionary choice -- to move from mat-sticker to hard shelly substrate -- ultimately is responsible for giving rise to attached animals such as crinoids," Babcock said. "This new species represents the link between the old lifestyle and the new lifestyle that became successful for this echinoderm lineage."
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April 30, 2019
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https://www.sciencedaily.com/releases/2019/04/190430132247.htm
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Evolving alongside viruses impacts susceptibility to future infections
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Researchers have shown that when fruit flies co-evolve with viruses, different genetic changes occur to those caused by encountering a virus for the first time, altering the insects' susceptibility to future infection.
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The findings, published in "Whether you look at humans or bacteria, you find some individuals are resistant to pathogen infection but others are susceptible," explains Frank Jiggins, Group Leader at the University of Cambridge, UK, and an author of the study. "These differences are frequently thought to result from co-evolution between pathogens and their hosts, and we wanted to formally test this idea using flies and viruses."The team used four species of fruit fly to compare genetic variation caused by naturally occurring (endemic) insect viruses, called sigma viruses, with variation caused by non-endemic viruses from other insect species. Within all four species of fruit fly, there was a significantly greater variation in susceptibility to the endemic sigma viruses than to viruses from other species. For example, there was a 1,294-fold increase in viral load (the number of viral particles) in one of the species of fruit fly for the non-endemic viruses, compared with the endemic virus. This suggested the flies were more susceptible to non-endemic virus infection.The team next investigated whether the genetic basis of resistance to the viruses was different for the endemic (co-evolved) and non-endemic viruses. They searched for known genetic variants in the fruit-fly genomes and looked at their effects on viral load. Their effect was greater on the endemic virus than on the viruses from other species, meaning that genetic variants which provide resistance to endemic sigma viruses do not protect against other virus species.These initial experiments sampled flies with diverse genetic make-up from a single location. To further investigate how virus co-evolution shapes fly genetics, the team mapped known resistance genes in a collection of genetically similar fruit flies from around the world. The results confirmed their earlier findings -- that there was considerably more genetic variation in susceptibility to the co-evolved virus than the non-endemic virus. The earlier result from a single fly population held true when sampling flies from across six continents."We have found greater genetic variation in susceptibility to viruses that naturally infect fruit flies compared to viruses that do not, suggesting that selection by these pathogens has acted to increase the amount of variation in susceptibility," concludes Ben Longdon, Sir Henry Dale Wellcome Trust and Royal Society Research Fellow at the University of Exeter, UK, and an author of the study. "Our results indicate that when a pathogen infects a novel host species, there may be far less genetic variation in susceptibility among individuals than is normally the case. This may leave populations vulnerable to epidemics of pathogens that have previously been circulated in other host species."
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April 29, 2019
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https://www.sciencedaily.com/releases/2019/04/190429154548.htm
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How the bumble bee got its stripes
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Researchers have discovered a gene that drives color differences within a species of bumble bees. This discovery helps to explain the highly diverse color patterns among bumble bee species as well as how mimicry -- individuals in an area adopting similar color patterns -- evolves. A study describing the gene, which occurs in a highly conserved region of the genome that provides blueprints for segmentation, was led by researchers at Penn State and appears April 29, 2019, in the journal
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"There is exceptional diversity in coloration of bumble bees," said Heather Hines, assistant professor of biology and of entomology at Penn State and principal investigator of the study. "Of the roughly 250 species of bumble bees, there are over 400 different color patterns that basically mix and match the same few colors over the different segments of a bee's body."The most common bumble bee color patterns feature red around a bee's tail, thought to advertise its dangerous sting. In spite of the great diversity available, color patterns tend to converge toward similarity within a particular geographic region because they serve as an important and effective warning signal. This is an example of Müllerian mimicry, where similar, often vibrant, color patterns are used among multiple species to warn predators of a dangerous feature like toxicity or sharp spines."Müllerian mimicry has served as an example of evolution since the days of Darwin," said Hines. "Studying these mimicry systems -- similar color patterns in many different species -- allows us to see how natural traits evolve. It can also tell us about how traits are encoded in the genome: is there only one way to make a trait, or do different species arrive at similar traits through different genetic pathways?"The research team investigated the genetic basis of color in the species The researchers performed a genome-wide association study, where researchers look for variation in DNA sequence associated with variation in a trait. They identified a regulatory region that changes expression in a gene called Abdominal-B, which drives the shift in color."Abdominal-B is located in a highly conserved region of the genome that contains important patterning genes referred to as "Hox genes," which act as blueprints for the segments of a developing bee larva," said Hines. "Usually any change to these Hox genes triggers many other important changes in the development of the animal's segments, but we weren't seeing those other changes. It turns out that the altered expression of Abdominal-B happens so late in development that it can have very specific effects on color without other consequences."The change in the regulatory region resulted in Abdominal-B being expressed in an unusual location late in pupal development; the same time in development that pigment is starting to show up in the bee. Abdominal-B is usually expressed closer to the tail of the bee, but in red-striped bees it is expressed in segments further up, causing a mid-abdominal color shift."It's possible that the expression of this gene and other Hox genes might move around late in development, allowing the mixing and matching within segments to create the modular color patterning that we see across bumble bees," said Hines.According to the researchers, this particular genetic change in the regulatory region was not responsible for color shifts in ten closely related species of bumble bees with similar red and black color variation. It is likely that these other species undergo genetic changes that target other regulatory regions of the same gene or different genes entirely. The researchers are continuing to investigate the genetics of color shifts across species."This tells us that the basis for color patterning in Bombus melanopygus arose independently from patterning in other species," said Hines. "Bumble bees do not share this similarity in color pattern because they all inherited it from a common ancestor, so there must be many diverse routes to mimicry."This study was also performed by Penn State researchers Li Tian, Sarthok Rasique Rahman, Briana Ezray, Patrick Lhomme, and Luca Franzini, and James Strange at Utah State University. This work was funded by a National Science Foundation CAREER grant to Hines.
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