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April 24, 2019
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https://www.sciencedaily.com/releases/2019/04/190424153623.htm
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With flower preferences, bees have a big gap between the sexes
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For scores of wild bee species, females and males visit very different flowers for food -- a discovery that could be important for conservation efforts, according to Rutgers-led research.
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Indeed, the diets of female and male bees of the same species could be as different as the diets of different bee species, according to a study in the journal "As we get a better sense of what makes flowers attractive to different kinds of bees, maybe we can get smarter about bee conservation," said lead author Michael Roswell, a doctoral student in the lab of senior author Rachael Winfree, a professor in the Department of Ecology, Evolution, and Natural Resources at Rutgers University-New Brunswick.Five years ago, when Winfree Lab members were evaluating federally funded programs to create habitat for pollinators, Roswell noticed that some flowers were very popular with male bees and others with females. That spurred a study to test, for as many wild bee species as possible, whether males and females visit different kinds of flowers.New Jersey is home to about 400 species of wild bees -- not including Apis mellifera Linnaeus, the domesticated western honeybee whose males do not forage for food, Roswell noted.The scientists collected 18,698 bees from 152 species in New Jersey. The bees visited 109 flower species in six semi-natural meadows with highly abundant and diverse flowers. The meadows were managed to promote mostly native flowers that attract pollinators.Female bees build, maintain, collect food for and defend nests, while male bees primarily seek mates. Both sexes drink floral nectar for food, but only females collect pollen that serves as food for young bees, so they forage at greater rates than males.From the flowers' standpoint, both female and male bees are important pollinators -- though female bees are more prolific because they spend more time foraging at flowers.Before mating, the males of some species travel from the area where they were born. Targeting their preferences for flowers may help maintain genetically diverse bee populations, Roswell speculated."We see some intriguing patterns, where certain plant families seem relatively preferred or avoided by male bees, or where males have relatively less appetite for visiting flowers that only produce pollen and not nectar," he said. "That could help pinpoint the right mix of flowers to improve bee conservation down the road."
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April 18, 2019
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https://www.sciencedaily.com/releases/2019/04/190418131248.htm
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Infamous 'death roll' almost universal among crocodile species
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The iconic "death roll" of alligators and crocodiles may be more common among species than previously believed, according to a new study published in
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Contrary to popular belief, crocodiles can't chew, so they use a powerful bite coupled with a full-bodied twisting motion -- a death roll -- to disable, kill, and dismember prey into smaller pieces. The lethal movement is characteristic of both alligators and crocodiles and has been featured in numerous movies and nature documentaries.Until now, the death roll had only been documented in a few of the 25 living crocodilian species, but how many actually do it?"We conducted tests in all 25 species, and 24 of them exhibited the behavior," said lead author Stephanie Drumheller-Horton, a paleontologist and adjunct assistant professor in the Department of Earth and Planetary Sciences at UT.For the research, Drumheller-Horton teamed up with Kent Vliet from the University of Florida and Jim Darlington, curator of reptiles at the St. Augustine Alligator Farm.It was previously believed that slender-snouted species, like the Indian gharial, didn't roll because their diets consist of small prey like fish, eaten whole.But it turns out that feeding isn't the only time the animals might roll."Aggression between individual crocodylians can become quite intense, often involving bites and death rolls in establishing dominance or competition for females," Vliet said.Paleosuchus palpebrosus, commonly called Cuvier's dwarf caiman, is the only species that did not perform a death roll under experimental conditions. "Although, it's also possible that they were just being uncooperative," said Darlington.And the fossil ancestors of modern crocodiles? If they share a similar body plan and lifestyle with their modern counterparts, it's likely that they could death roll, too."Crocodile relatives have played the role of semi-aquatic ambush predator since the Age of Dinosaurs," said Drumheller-Horton.Whether in the Northern Territories of Australia, a lake in the Serengeti, or a watering hole in the late Cretaceous, chances are that a patient predator is waiting in the water to surprise its next meal with a burst of speed, a powerful bite, and a spinning finish.
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New Species
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April 10, 2019
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https://www.sciencedaily.com/releases/2019/04/190410105649.htm
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Long-lived bats could hold secrets to mammal longevity
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University of Maryland researchers analyzed an evolutionary tree reconstructed from the DNA of a majority of known bat species and found four bat lineages that exhibit extreme longevity. They also identified, for the first time, two life history features that predict extended life spans in bats.
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Their work is described in a research paper, published in the April 10, 2019 issue of the journal "Scientists are very interested in finding closely related species in which one is long lived and one is short lived, because it implies that there has been some recent change to allow one species to live longer," said Gerald Wilkinson, a biology professor at UMD and lead author of the paper. "This study provides multiple cases of closely related species with varying longevity, which gives us many opportunities to make comparisons and look for some underlying mechanism that would allow some species to live so long."Longevity is often correlated to body size, with larger animal species generally living longer than smaller ones. For example, an African elephant can live as long as 70 years, while a common house mouse typically lives only one to three years. Humans are considered relatively long-lived animals, tending to live about four times longer than most other mammals when adjusted for size. But bats can far exceed that. Some species can live 40 years -- eight times longer than similarly sized mammals -- which is why scientists have long sought to understand bats as a model for healthy aging.This is the first time researchers have reconstructed longevity on an evolutionary tree of bats and used that information to compare traits that could account for life span differences between related species. Wilkinson and his coauthor, UMD biological sciences graduate student Danielle Adams, analyzed traits that were known to correlate with longevity -- body size, cave use and hibernation -- as well as traits that had not been previously considered, such as home-range latitude and size differences between males and females.The researchers found that hibernating bat species located in more extreme latitudes live longer than those closer to the equator. Wilkinson said the researchers can't say for sure how latitude impacts longevity, but their study suggests it may have to do with these bats' ability to allow their body temperature to fluctuate. Because higher latitudes tend to require longer hibernation periods, hibernating bats must be able to adjust their body temperature, allowing it to drop significantly during hibernation and rewarm during active times."Of the lineages of bats that live a long time, three of them are hibernators and one of them is the vampire bat," said Wilkinson, who is also associate dean for faculty affairs in the College of Computer, Mathematical, and Natural Sciences at UMD. "The vampire bat is very unusual for a mammal in that it can let its body temperature rise and fall throughout the day."This ability allows a vampire bat to conserve energy if it fails to obtain a blood meal. Scientists have previously suggested that the ability to tolerate variations in body temperature may enable some mammals to fight infection better than those without that ability. This happens to a limited extent in humans when the immune system attempts to kill a virus or bacterial infection by raising body temperature and causing a fever.Not all adaptations extend life span, however. Identifying traits that correspond with shorter life spans is also important to understanding longevity. This study showed that bat species in which males are larger than females have shorter life spans than those in which males are the same size or smaller than females.In the majority of bat species, females are larger than males. (Scientists have speculated that this could be due to the need for females to fly while pregnant and carry their young.) But in some tropical bat species, males are larger than females. Among these bats, competition for females may have led to male-on-male aggression that favored the evolution of larger male body size. According to Wilkinson, over time, the shift to larger and larger males would have been advantageous to males seeking mates, but sexual conflict might also have led to greater mortality. Over time, high mortality rates from aggression may have led to shorter species life spans, because traits that confer physical dominance would have been more important than those that extend life span.The researchers hope this work can pave the way for more comparative studies that will explain why certain traits are associated with life span."If we lived as long as bats, adjusted for size, we could live 240 years," Wilkinson said. "Everybody wants to know how these animals can live so long. This kind of work can help us get to the answers."
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New Species
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April 9, 2019
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https://www.sciencedaily.com/releases/2019/04/190409093747.htm
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New wasps named after biscuits and Doctor Who aliens
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University of Adelaide researchers were inspired by everything from chocolate biscuits and Doctor Who aliens when choosing names for 10 new species of wasps.
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"I named one wasp While the new species "Zygon aliens consume their host whilst inhabiting them, a trait particularly relevant to parasitic wasps," says Dr Fagan-Jeffries.These wasps inject their eggs into live caterpillars, and the baby wasps slowly eat the caterpillar from the inside out. As gruesome as it sounds, they are very important in ecosystems for regulating native caterpillar populations.One of the new wasps, "Less than 10% of this group of wasps have scientific names, which is why programs like Bush Blitz are so vital. We have discovered over 1,660 new species since 2010, and 17 of those are wasps," says Jo Harding Bush Blitz Manager.Taxonomy, the scientific discipline of describing new species, is vital for understanding and documenting the living things around us. "Until taxonomists name and formally describe a species, it is difficult for other researchers, such as those working in conservation, or biological control, to do anything with it," says Ms Harding.Inspirational taxonomists and entomologists that helped Dr Fagan-Jeffries collect vital specimens for this research, as well as those who feature prominently throughout her career, were also honoured with species named after them."I always loved insects in school, and I had a lot of incredible support from entomologists, back then and also during my PhD, who fuelled my passion for following a scientific career path," Dr Fagan-Jeffries says. "Naming species after those people is just a tiny way of saying thank you."Species named after researchers include
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New Species
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April 9, 2019
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https://www.sciencedaily.com/releases/2019/04/190409083242.htm
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Underwater forests a treasure trove of new drugs
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Defensive compounds produced by microbes are a major source of antibiotics and other important medicines. But with resistant bugs appearing faster than potential allies, researchers are taking their search for drug candidates offshore.
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Published in Almost a century since Fleming discovered penicillin in a stray mold, scientists continue to look to microbes for new antibiotics and other medicines. To date, none has given more generously than the Actinobacteria: a family of soil- and seabed- dwelling bacteria who think they're fungi."About half of the 20,000+ microbe-derived drug candidates currently known come from Actinobacteria," says senior study author Dr. Maria de Fátima Carvalho of the Interdisciplinary Center of Marine and Environmental Research (CIIMAR), Portugal. "Now the supply of new species on land -- where they form spores and branched networks just like a fungus -- is beginning to run out."But relatively underexplored marine Actinobacteria may yet prove an even richer source of bioactive microbial molecules."Several novel drug leads derived from marine Actinobacteria are already known," says Carvalho. "These include anticancer agent salinosporamide A, currently in clinical trials, and several new antibiotics that are effective against drug-resistant infections like MRSA and tuberculosis."Predominantly found in sediments on the sea floor, Actinobacteria can also live inside other organisms that live and feed there -- including brown algae (seaweed)."The brown alga In other kelp species, Actinobacteria are known to provide protective compounds in exchange for nutrients and shelter, which could be a source of new drug candidates.Carvalho's team analyzed a sample of "After six weeks of culture in the lab, we isolated 90 Actinobacterial strains from the sample."Extracts from these Actinobacteria were then screened for antimicrobial and anticancer activity."Forty-five of the Actinobacterial extracts inhibited growth of Candida albicans, Staphylococcus aureus, or both."Some extracts were active against these common pathogens even at extremely low concentrations, making them promising candidates for the discovery of antimicrobial drugs. Several also showed selective anticancer activity."Seven of the extracts inhibited growth of breast and particularly nerve cell cancers, while having no effect on non-cancer cells.""This study reveals that the seaweed Further tests on the most potent of these strains revealed that some of the effects are likely the result of newly discovered compounds."We identified extracts from two Actinobacteria strains that do not match any known compounds in the most comprehensive international database of natural bioactive compounds. We intend to follow up on these exciting results."
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New Species
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April 8, 2019
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https://www.sciencedaily.com/releases/2019/04/190408161633.htm
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Some woodpeckers imitate a neighbor's plumage
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In the first global test of the idea, scientists have found evidence that some woodpeckers can evolve to look like another species of woodpecker in the same neighborhood. The researchers say that this "plumage mimicry" isn't a fluke -- it happens among pairs of distantly related woodpeckers all over the world. The study, published in the journal
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"Habitat, climate, and genetics play a huge role in the way feather color and pattern develop," explains lead author Eliot Miller at the Cornell Lab. "Species in similar environments can look similar to one another. But in some cases, there's another factor influencing the remarkable resemblance between two woodpecker species and that's mimicry. It's the same phenomenon found in some butterflies which have evolved markings that make them look like a different bad-tasting or toxic species in order to ward off predators."Study authors combined data on feather color, DNA sequences, eBird reports, and NASA satellite measures of vegetation for all 230 of the world's woodpecker species. It became clear, Miller says, that there have been repeated cases of distantly-related woodpeckers coming to closely resemble each other when they live in the same region of the globe."In North America, the classic lookalike pairing is Downy Woodpecker and the larger Hairy Woodpecker," Miller says. "Our study suggests that these two species have evolved to look nearly identical above and beyond what would be expected based on their environment. Yet, these two species evolved millions of years apartOther North American lookalikes are Black-backed and Three-toed Woodpeckers. In Europe, Greater and Lesser Spotted Woodpeckers bear a striking resemblance, as do the Lineated, Robust, and Helmeted Woodpeckers of South America.Though not part of the study, Miller's take on the reason for woodpecker dopplegangers is that downies that look like the larger, more aggressive Hairy Woodpeckers might make other birds, such as nuthatches and titmice, think twice about competing with the downy for food. Some evidence supporting this idea has been found in observational studies but field experiments would be needed to more conclusively test this hypothesis.The data turned up some other interesting connections between woodpecker appearance and habitat. Many of the woodpeckers the scientists looked at in tropical regions have darker feathers. This adds to a growing body of evidence in support of "Gloger's Rule," which states that organisms tend to be darker colored in more humid areas. They also found that:Additional studies would be needed to try to ferret out why some plumage patterns seem to be linked to habitat types."It's really fascinating," says Miller. "And it's pretty likely this is happening in other bird families, too. I first got interested in this question a decade ago from looking through bird books. I wondered how the heck some distantly related species could look so much alike -- what are the odds that it could happen just by chance?"
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New Species
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April 5, 2019
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https://www.sciencedaily.com/releases/2019/04/190405144853.htm
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Scientists explore causes of biodiversity in perching birds
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New research by a global team of scientists has resulted in significant strides in ornithological classification and identified possible causes of diversity among modern bird species.
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The study, coauthored by researchers at the University of Tennessee, Knoxville and published in Scientists analyzed genetic samples and fossils of all major groups within the passerine family to better understand the way these species are related. The large data set allowed for much more accurate inferences into the development of perching birds.The result is the most accurate and comprehensive "tree of life" of passerine species to date.The report also includes an analysis of the impact some events in Earth's history could have had on passerines' biodiversity."Our main discovery is that the evolution of perching birds around the world was determined in part by connections between continents over the Earth's history, as well as changes in global climate," said Michael Harvey, a postdoctoral fellow with UT's Department of Ecology and Evolutionary Biology. "We found, for example, evidence that glaciations during the Oligocene Epoch (between 24 and 33 million years ago) wiped out a lot of perching birds, but that the warming period immediately after prompted the evolution of many of the groups of perching birds alive today."Another large portion of the study looks at the origin of perching birds, including a finding that perching birds originated on the Australian landmass around 47 million years ago."However, not just one single event in earth's history explains how they became so diverse and widespread," said Elizabeth Derryberry, UT assistant professor of ecology and evolutionary biology. "Instead, diversification and dispersal of this group has been affected by a number of different climatological and geological events, such as glaciation, global temperature changes and colonization of new continents."According to Harvey, the next step is to fill in the missing gaps in passerine evolution not fully explained by Earth's history."We found that changes in geology and climate cannot explain everything," he said. "Future research needs to focus on explaining those aspects of bird evolution that are not determined by the Earth's geological and climatic history, but instead by the evolution of new characteristics in the birds themselves. For example, did the evolution of the ability to complete long-distance migrations in some perching birds help them get to new areas, or lead to the evolution of new species?"Derryberry believes the research serves as a template for future exploration."The study provides a framework for how to conduct these types of analyses on large radiations and should provide a path forward for this type of research on all birds," she said.
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New Species
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April 4, 2019
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https://www.sciencedaily.com/releases/2019/04/190404124755.htm
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Jurassic crocodile discovery sheds light on reptiles' family tree
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A newly identified species of 150 million-year-old marine crocodile has given insights into how a group of ancient animals evolved.
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The ancestor of today's crocodiles belonged to a group of animals that developed a tail fin and paddle-like limbs for life in the sea, resembling dolphins more than crocodiles.These slender animals, which fed on fast-moving prey such as squid and small fish, lived during the Jurassic era in shallow seas and lagoons in what is now Germany. Related species have previously been found in Mexico and Argentina.An international team of scientists, including researchers from Germany and the University of Edinburgh, identified the new species from a remarkably well-preserved skeleton.The fossil was discovered in 2014 in a quarry near the town of Bamberg in Bavaria, Germany by a team from the Naturkunde-Museum Bamberg, where it is now housed. The species, Cricosaurus bambergensis, takes its name from the town.Researchers compared the fossil with those from other museum collections, and confirmed that it was a previously unseen species.The skeleton has several distinguishing features in its jaws, the roof of its mouth and tail, some of which have not been seen in any other species.Experts created digital images of the fossil in high resolution, to enable further research. They expect the fossil will aid greater understanding of a wider family of ancient animals, known as metriorhynchid, to which this species belonged.The research, carried out with Naturkunde-Museum Bielefeld, Eberhard-Karls Universität Tübingen and commercial partners Palaeo3D, is published in Dr Mark Young, of the University of Edinburgh's School of GeoSciences, who took part in the study, said: "The rock formations of southern Germany continue to give us fresh insights into the age of dinosaurs. These rock layers were deposited at a time when Europe was covered by a shallow sea, with countries such as Germany and the UK being a collection of islands."Sven Sachs, from the Naturkunde-Museum Bielefeld, who led the project, said: "The study reveals peculiar features at the palate that have not been described in any fossil crocodile so far. There are two depressions which are separated by a pronounced bar. It is not clear what these depressions were good for."
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New Species
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April 3, 2019
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https://www.sciencedaily.com/releases/2019/04/190403135041.htm
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Thirteen new ant species discovered in Hong Kong
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"If you believe that all life surrounding you in Hong Kong has been discovered, then you'll realise that you just need to look a bit closer... not for big things, but for ants and other insects walking at your feet, to find a plethora of new creatures," said Dr Benoit Guénard from the School of Biological Sciences of the University of Hong Kong (HKU).
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In two separate articles recently published in Among those are three new species of the genus "Strumigenys," also known as miniature trap-jaw ants, new to Science and thus far known only from Hong Kong. As their name indicates, these species are tiny, measuring only 2 to 4mm long but are astounding predators of the small arthropods living in the forest leaf-litter. They can open their mandibles widely and snap their prey with the fast-closing movement of their mandibles.The new species described by a recent HKU graduate student Wilfred Kit Lam Tang, and the researchers Mr. Mac Pierce and Dr Benoit Guénard, are named Ken Bradley, Chairman of the Hong Kong Natural History Society said that the Society readily supports Dr. Guénard's research which is line with the Society's objective of "encouraging the study of Natural History in general and in particular in Hong Kong." "There are still many species in Hong Kong to be discovered and the support and involvement from the community in this endeavour is absolutely fundamental," said Dr. Guénard.Another five species of Indeed, five of the species newly recorded are non-native to Hong Kong, four belonging to the The discovery of five more exotic species in Hong Kong, like the fire ants (Monitoring Hong Kong insects can thus reveal both beautiful and alarming discoveries. With probably several hundreds, if not thousands of species waiting to be found, it shows the fantastic diversity that the city still has to offer if protected sufficiently. In parallel, it also represents an important step for uncovering more alarming species, in particular exotic ones for which early detection represents a key requirement to ensure success in the limitation of their spread and negative impacts.
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New Species
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April 2, 2019
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https://www.sciencedaily.com/releases/2019/04/190402081530.htm
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New species of wood-munching clams found at the bottom of the ocean
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When a tree falls in a forest, regardless of whether anyone hears it, it sometimes becomes clam food. Wood that finds its way from rivers into the ocean can eventually become waterlogged and sink to the sea floor, sometimes to great depths. There, tiny clams bore into the wood, eating the wood shavings and living the rest of their lives head down in the holes they made. In a new paper in the
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All clams are aquatic animals with two shells covering a soft, squishy body. Wood-boring clams have a special feature -- since they bury themselves deep in sunken pieces of wood, they have long, tube-like organs called siphons that extend out from their shells into the ocean water, so they can pull in water and extract oxygen from it with their gills. But it's the clams' diets that make them really unique. They're able to flex their muscles and rock their shells against the wood, scraping off little bits. The clams then eat this sawdust and digest it with help from special bacteria in their gills. Along with termites and shipworms, they're some of the only animals on Earth that can eat wood. And, as the new study revealed, there are a lot more fundamentally different kinds of them than originally thought."There's not just one tree-cleaner-upper in the ocean, they're really diverse," says Janet Voight, Associate Curator of Invertebrate Zoology at the Field Museum and the study's lead author. "Imagine living at the bottom of the ocean as a tiny swimming clam; you either have to find a sunken piece of wood or die. You wouldn't think there'd be that many kinds of clams doing this. But we've now found that there are six different groups, called genera, and around sixty different species."When a new organism, whether it's a clam or a frog or a tree, is discovered by scientists, they classify it with a name that tells where it belongs in its family tree. Just like we can give more and more specific locations by going from continent to country to state to city to street, scientists place animals into increasingly specific categories of order, family, genus, and species. In this paper, Voight and her colleagues examined a wide variety of members of the deep-sea wood-eating clam family. By looking at the clams themselves and studying their DNA, the researchers determined that there are at least six different genera (plural of "genus") that make up the family. Three of these genera are described for the first time in this paper. The researchers also determined that there was one previously undiscovered species lurking in museum collections of these clams.The importance of the physical differences between the groups aren't immediately apparent. To help confirm the grouping suggested by the animals' physical characteristics, the researchers ran a DNA analysis of the specimens. "You think, am I seeing everything that's there, are there cryptic species, am I over-splitting them and going crazy? It's really scary checking yourself against the DNA, but the results matching what I found gave me a lot of confidence," says Voight.The new genera are named While the clams are tiny (some have shells smaller than a pea even as adults), they can settle in massive numbers, making the clams an important factor in the health of their deep-sea ecosystems. "We have no idea how much wood is at the bottom of the ocean, but there's probably a lot more than we think," says Voight. "After big storms, we estimate that millions of tons of wood are washed out to sea. What if these clams weren't there to help eat it? Think how long it would take the wood to rot. The clams contribute to the cycling of carbon, they play an integral part in making the wood into something that the other animals at the bottom of the ocean can get energy from. It could even affect sea level rise. It blows me away."
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New Species
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April 1, 2019
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https://www.sciencedaily.com/releases/2019/04/190401115909.htm
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The evolution of bird-of-paradise sex chromosomes revealed
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Birds-of-paradise are a group of songbird species, and are known for their magnificent male plumage and bewildering sexual display. Now, an international collaborative work involving Dept. of Molecular Evolution and Development of University of Vienna, Zhejiang University of China, and Swedish Museum of Natural History analyzed all together 11 songbird species genomes, including those of five bird-of-paradise species, and reconstructed the evolutionary history of their sex chromosomes.
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Birds have an opposite type of sex chromosomes to that of mammals. That is, females have one Z chromosome and one female-specific W chromosome, while males have two Z chromosomes. The W chromosome is much smaller and gene-poor, similar to the Y chromosome of human. By sequencing the female songbird genomes, the researchers now uncovered the details of how Z and W chromosomes had become separated for their evolutionary trajectories, and which factors dictate the fates of the genes on the W chromosome.Sex chromosomes are not supposed to have genetic exchange with each other for most of the regions. That is, they evolve along separate evolutionary trajectories; so that sex-determining genes will not be recombined from one sex chromosome to the other, then appear in the opposite sex. The researchers showed that such suppression of recombination has occurred at four time points between the songbird sex chromosomes. This has reshaped four consecutive sex-linked regions to form a gradient of time-associated divergence pattern, termed 'evolutionary strata'. Despite the dramatically diverse phenotypes of all extant 5,000 songbird species, all of them seem to share the same evolutionary history of these recombination suppression events. What has caught the attention of the researchers is, one family of repetitive elements (called 'CR1 transposon'), presumably non-functional DNA sequences have massively accumulated at a mutation hotspot located between the two neighboring evolutionary strata. This brought the hypotheses that junk DNAs may have triggered the loss of recombination between sex chromosomes, and subjected them for separate evolution paths.Once recombination is lost on the W chromosome (Z chromosomes can still recombine only in males), genes cannot resist the invasion of deleterious mutations, as normally they can be effectively purged by recombination. This is the price of sex that the sex chromosome (either the human Y or the bird W) has to pay. Nowadays only a handful of genes are retained functional on the songbird W chromosomes due to such long-term genetic erosion. The researchers found the retained genes tend to be more broadly or highly expressed than any other genes that have become lost in non-avian species, where both sets of genes still exist. This indicates that the retained genes have more important functions than others, and losing them, even when the Z-linked gene still exists in female, is too costly for the species to bear a reduced dosage.
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New Species
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March 28, 2019
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https://www.sciencedaily.com/releases/2019/03/190328150803.htm
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What's in this plant? The best automated system for finding potential drugs
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Researchers at the RIKEN Center for Sustainable Resource Science (CSRS) in Japan have developed a new computational mass-spectrometry system for identifying metabolomes--entire sets of metabolites for different living organisms. When the new method was tested on select tissues from 12 plants species, it was able to note over a thousand metabolites. Among them were dozens that had never been found before, including those with antibiotic and anti-cancer potential.
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The common pain reliever aspirin (acetylsalicylic acid) was first made in the 19th century, and is famously derived from willow bark extract, a medicine that was described in clay tablets thousands of years ago. After a new method of synthesis was discovered, and after it had been used around the world for almost 70 years, scientists were finally able to understand how it works. This was a long historical process, and while plants remain an almost infinite resource for drug discovery and biotechnology, thousands of years is no longer an acceptable time frame.The biggest problem is that there are millions of plant species and each has its own metabolome--the set of all products of the plant's metabolism. Currently, we only know about 5% of all these natural products. Although mass spectrometry can identify plant metabolites, it only works for determining if a sample contains a given molecule. Searching for as-yet-unknown metabolites is another story.Computational mass spectrometry is a growing research field that focuses on finding previously unknown metabolites and predicting their functions. The field has established metabolome databases and repositories, which facilitate global identification of human, plant, and microbiota metabolomes. Led by Hiroshi Tsugawa and Kazuki Saito, a team at CSRS has spent several years developing a system that can quickly identify large numbers of plant metabolites, including those that have not been identified before.As Tsugawa explains, "while no software can comprehensively identify all the metabolites in a living organism, our program incorporates new techniques in computational mass spectrometry and provides 10 times the coverage of previous methods." In tests, while mass spectrometry-based methods only noted about one hundred metabolites, the team's new system was able to find more than one thousand.The new computational technique relies on several new algorithms that compare the mass spectrometry outputs from plants that are labeled with carbon-13 with those that are not. The algorithms can predict the molecular formula of the metabolites and classify them by type. They can also predict the substructure of unknown metabolites, and based on similarities in structure, link them to known metabolites, which can help predict their functions.Being able to find unknown metabolites is a key selling point for the new software. In particular, the system was able to characterize a class of antibiotics (benzoxazinoids) in rice and maize as well as a class with anti-inflammatory and antibacterial properties (glycoalkaloids) in the common onion, tomato, and potato. It was also able to identify two classes of anti-cancer metabolites, one (triterpene saponins) in soy beans and licorice, and the other (beta-carboline alkaloid) in a plant from the coffee family.In addition to facilitating the screening of plant-specialized metabolomes, the new process will speed up the discovery of natural products that could be used in medicines, and also increase understanding of plant physiology in general.As Tsugawa notes, use of this new method is not limited to plants. "I believe that computationally decoding metabolomic mass spectrometry data is linked to a deeper understanding of all metabolisms. Our next goal is to improve this methodology to facilitate global identification of human and microbiota metabolomes as well. Newly found metabolites can then be further investigated via genomics, transcriptomics, and proteomics."
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New Species
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March 28, 2019
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https://www.sciencedaily.com/releases/2019/03/190328112519.htm
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Five new frog species from Madagascar
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Scientists at Ludwig-Maximilians-Universitaet (LMU) in Munich and the Bavarian State Collection of Zoology have named five new species of frogs found across the island of Madagascar. The largest could sit on your thumbnail, the smallest is hardly longer than a grain of rice.
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Madagascar, an island a little larger than mainland France, has more than 350 frog species. This number of recognized species is constantly rising, and many of the newly named species are very small.Mark D. Scherz, a PhD candidate at LMU Munich, and Dr. Frank Glaw, Head of the Herpetology Section at the Bavarian State Collection of Zoology in Munich, together with colleagues at the Technical University of Braunschweig and the University of Antananarivo have named five new species of tiny frogs found across the island. Their study appears in the online journal The five new species belong to a group of frogs commonly referred to as 'narrow-mouthed' frogs, a highly diverse family found on every continent except Antarctica and Europe. Although most narrow-mouthed frogs are small to moderately large, many are tiny. In fact, the group includes the smallest frog in the world -- "When frogs evolve small body size, they start to look remarkably similar, so it is easy to underestimate how diverse they really are," says Mark D. Scherz, lead author on the new study. "Our new genus name, Finding tiny frogs in the leaf litter is hard work. "Calling males often sit one or two leaves deep and stop calling at the slightest disturbance," says Frank Glaw. "It can take a lot of patience to find the frog you are looking for."
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New Species
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March 28, 2019
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https://www.sciencedaily.com/releases/2019/03/190328102626.htm
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What 'Big Data' reveals about the diversity of species
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"Big data" and large-scale analyses are critical for biodiversity research to find out how animal and plant species are distributed worldwide and how ecosystems function. The necessary data may come from many sources: museum collections, biological literature, and local databases. Researchers at the University of Göttingen have investigated how this wealth of knowledge can best be integrated so that it can be transported into the digital age and used for research. The results were published in the journal
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Biodiversity data can describe different aspects of life, for example the geographical distribution of organisms, their ancestry, ecological characteristics or interactions with their environment. In addition, each of these aspects can be described by different data types. For example, some researchers characterise the range of distribution of a species using individual occurrences, others use systematic counts or checklists of regional species. The individual data types not only differ in their availability, but can also have a significant influence on the scientific results and conclusions. The authors advocate for biodiversity research to use as many concurrent data sources as possible to better understand the complex interactions in nature, especially considering the increasing threat to species and ecosystems worldwide."The resolution of the data is crucial for the accuracy and reliability of studies on biodiversity," says the first author Dr Christian König from the Department of Biodiversity, Macroecology and Biogeography. The fundamental compromise here is that the more detailed the data, the lower its availability and representativeness on a global scale -- and often the data gaps are particularly large where species diversity is particularly high. The researchers prove this relationship by means of two case studies in which they model global patterns in the growth habit and seed size of plant species using different data types. "Our biodiversity models will improve if we link all the available biodiversity data together and make the best possible use of them, but there has been a lack of conceptual understanding of their basic characteristics and common synergies," adds Professor Holger Kreft, Head of Department.
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New Species
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March 28, 2019
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https://www.sciencedaily.com/releases/2019/03/190328080354.htm
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Galápagos islands have nearly 10 times more alien marine species than once thought
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Over 50 non-native species have found their way to the Galápagos Islands, almost 10 times more than scientists previously thought, reports a new study in
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The study, a joint effort of the Smithsonian Environmental Research Center, Williams College, and the Charles Darwin Foundation, documents 53 species of introduced marine animals in this UNESCO World Heritage Site, one of the largest marine protected areas on Earth. Before this study came out, scientists knew about only five."This increase in alien species is a stunning discovery, especially since only a small fraction of the Galápagos Islands was examined in this initial study," said Greg Ruiz, a co-author and marine biologist with the Smithsonian Environmental Research Center."This is the greatest reported increase in the recognition of alien species for any tropical marine region in the world," said lead author James Carlton, an emeritus professor of the Maritime Studies Program of Williams College-Mystic Seaport.The Galápagos lie in the equatorial Pacific, roughly 600 miles west of Ecuador. Made famous by Charles Darwin's visit in 1835, the islands have long been recognized for their remarkable biodiversity. But with their fame, traffic has spiked. In 1938, just over 700 people lived on the Galápagos. Today, more than 25,000 people live on the islands, and nearly a quarter-million tourists visit each year.Carlton and Ruiz began their study in 2015, with Inti Keith of the Charles Darwin Foundation. They conducted field surveys on two of the larger Galápagos Islands: Santa Cruz and Baltra, where they hung settlement plates from docks one meter underwater to see what species would grow on them. They also collected samples from mangrove roots, floating docks and other debris and scoured the literature for previous records of marine species on the islands.The team documented 48 additional non-native species in the Galápagos. Most of them (30) were new discoveries that could have survived on the islands for decades under the radar. Another 17 were species scientists already knew lived on the Galápagos but previously thought were native. One final species, the bryozoan Watersipora subtorquata, was collected in 1987 but not identified until now.Sea squirts, marine worms and moss animals (bryozoans) made up the majority of the non-native species. Almost all of the non-natives likely arrived inadvertently in ships from tropical seas around the world. Some of the most concerning discoveries include the bryozoan Amathia verticillata -- known for fouling pipes and fishing gear and killing seagrasses -- and the date mussel Leiosolenus aristatus, which researchers have already seen boring into Galápagos corals."This discovery resets how we think about what's natural in the ocean around the Galápagos, and what the impacts may be on these high-value conservation areas," Carlton said.To reduce future invasions, the Galápagos already have one of the most stringent biosecurity programs in the world. International vessels entering the Galápagos Marine Reserve may anchor in only one of the main ports, where divers inspect the vessel. If the divers find any non-native species, the vessel is requested to leave and have its hull cleaned before returning for a second inspection.Still, the authors say, the risks remain high. The expansion of the Panama Canal in 2015 may bring the Indo-Pacific lionfish -- a major predator in the Caribbean -- to the Pacific coast of Central America. Once there, it could make its way to the Galápagos, where the likelihood of its success would be very high. Another possible arrival is the Indo-Pacific snowflake coral, which has already caused widespread death of native corals on the South American mainland.
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New Species
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March 27, 2019
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https://www.sciencedaily.com/releases/2019/03/190327161249.htm
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New cryptic bird species discovered
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In the lush, lowland rainforests on the island of Borneo lives a rather common, drab brown bird called the Cream-vented Bulbul, or Pycnonotus simplex. This bird is found from southern Thailand to Sumatra, Java and Borneo. In most of its range, it has white eyes. On Borneo, however, most individuals have red eyes, although there are also a few with white eyes. For 100 years, naturalists have thought the eye-color difference on Borneo was a trivial matter of individual variation. Through persistent detective work and advances in genetic sequencing technology, Louisiana State University Museum of Natural Science researchers have discovered that the white-eyed individuals of Borneo in fact represent a completely new species. Their discovery of the Cream-eyed Bulbul, or
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"One of the reasons we knew we had a new species as opposed to just a variant of another species was because the two populations -- the red-eyed and white-eyed populations -- actually occur together on Borneo. You can go to a site and see both of these birds. One of the theories of speciation is if two birds co-occur in the same area, and they are not interbreeding, then that's a definitive sign that they are different species," said Subir Shakya, lead author and LSU Department of Biological Sciences Ph.D. student.Shakya made the discovery after he had returned to LSU from an expedition to Sumatra. Back at LSU, he was sequencing the DNA of several bird specimens from Sumatra and comparing them to specimens from other sites in the region to determine the degree of genetic relatedness of various species from the different islands and the mainland of Asia, which is a common practice after returning from fieldwork. Several bulbuls from Borneo and the surrounding region were among the specimens he compared; however, the white-eyed Cream-vented Bulbuls from Borneo appeared genetically distinct from all the other white-eyed and red-eyed Cream-vented Bulbuls he examined. Further work to understand this discrepancy led to the conclusion that the white-eyed birds from Borneo were in fact a new species."We had found white-eyed individuals of the bulbul in old-growth hill forest in Crocker Range National Park in 2008 and in Lambir Hills National Park in 2013; and a group from the Smithsonian found them in Batang Ai National Park in 2018. All of these areas are in Malaysian Borneo," said co-author Fred Sheldon, the LSU Museum of Natural Science curator of genetic resources and Shakya's Ph.D. advisor.Specimens are preserved at the LSU Museum of Natural Science, which houses the world's largest collection of genetic samples of birds from Borneo and Sumatra as well as the Smithsonian and University of Kansas Museum. White-eyed and red-eyed individuals look almost exactly the same, except for eye color."This discovery was made due to Subir's dogged detective work, and a little serendipity," Sheldon said.
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New Species
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March 20, 2019
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https://www.sciencedaily.com/releases/2019/03/190320140453.htm
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New short-tailed whip scorpion species discovered in Amazon
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A new species of
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Schizomids are rare, small arachnids that are found in humid tropical and subtropical forests, mainly in leaf litter, caves, tree bark or under stones. They are all known as short-tailed whip scorpions due to the presence of a short flagellum -- a lash-like appendage -- in males and females. The flagellum of the male is held by the female's chelicerae -- appendages in front of the mouth -- during copulation in what is known as the mating march. But relatively little is known about the different shapes of male flagellum within The authors named this new species, collected in the eastern Amazon,
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New Species
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March 20, 2019
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https://www.sciencedaily.com/releases/2019/03/190320102221.htm
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Ant larvae fight the offspring of parasitic queens
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In certain ant species, queens invade the colonies of other species, kill the host queen or queens and lay their eggs in the host nest. After this, the host workers tend to the offspring of the parasitic queen as if their own, just as a bird hatching an egg laid by a cuckoo.
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"It's a disaster for the host nest, since without a queen production of its own offspring ceases. This is why defending the host nest from parasites is extremely important," says Unni Pulliainen, a doctoral student at the Faculty of Biological and Environmental Sciences, University of Helsinki, Finland.Researchers have recently found that the larvae of the host species are far from passive bystanders; rather, they may actually be active parties in such situations."The larvae of the host ants eat the eggs of the parasitic queen. In other words, they may contribute to defending the nest against parasitic ants that threaten the future of the entire nest."Six ant species from the "We also wanted to find out what the eggs smell like, as this specific characteristic is most likely what larvae use to distinguish the origin of the eggs. However, we are still looking for an answer to the biggest question of all: how do larvae smell anything in the first place? Adult ants smell with their antennae, which larvae don't have. This is a good question for further research," Pulliainen states.
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New Species
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March 14, 2019
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https://www.sciencedaily.com/releases/2019/03/190314111010.htm
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As uniform as cloned soldiers, new spiders were named after the Stormtroopers in Star Wars
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Despite being widely distributed across north and central South America, bald-legged spiders had never been confirmed in Colombia until the recent study by the team of Drs Carlos Perafan and Fernando Perez-Miles (Universidad de la Republica, Uruguay) and William Galvis (Universidad Nacional de Colombia). Published in the open-access journal
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Four of the novel spiders were unable to fit into any already existing genus, so the scientists had to create a brand new one for them, which they called Considered to be amongst the most enigmatic in the group of mygalomorphs, the bald-legged spiders are a family of only 11 very similarly looking, small- to medium-sized species, whose placement in the Tree of Life has long been a matter of debate. In fact, it is due to their almost identical appearance and ability for camouflage that became the reason for the new bald-legged spider genus to be compared to the fictional clone troopers.One of the most striking qualities of the bald-legged spiders (family Paratropididae) is their ability to adhere soil particles to their cuticle, which allows them to be camouflaged by the environment."The stormtroopers are the soldiers of the main ground force of the Galactic Empire. These soldiers are very similar to each other, with some capacity for camouflage, but with unskillful movements, like this new group of spiders," explain the researchers."We wanted to make a play on words with the name of the known genus, Paratropis, and of course, we also wanted to pay tribute to one of the greatest sagas of all time," they add.One of the new 'stormtrooper' species (In the course of their fieldwork, the researchers also confirmed previous assumptions that the bald-legged spiders are well adapted to running across the ground's surface. The spiders were seen to stick soil particles to their scaly backs as a means of camouflage against predators. More interestingly, however, the team records several cases of various bald-legged species burrowing into ravine walls or soil -- a type of behaviour that had not been reported until then. Their suggestion is that it might be a secondary adaptation, so that the spiders could exploit additional habitats.In conclusion, not only did the bald-legged spiders turn out to be present in Colombia, but they also seem to be pretty abundant there. Following the present study, three genera are currently known from the country (
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New Species
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March 13, 2019
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https://www.sciencedaily.com/releases/2019/03/190313132239.htm
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No super-Drosophila: Vinegar fly species have a good vision or olfaction, but not both
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The authors such as Ian Keesey, Markus Knaden and Bill Hansson had observed different behavior in earlier studies on the black-bellied vinegar fly
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In order to test their tradeoff hypothesis, the researchers examined the forms and functions of eyes and antennae as well as the associated visual and olfactory brain structures of a total of 62 "The detailed analysis of eyes and antennae revealed the whole spectrum of the trade-off between vision and olfaction: we found species that had invested primarily in vision, species where vision and olfaction are about equal, and species that rely primarily on their olfactory sense, but none of the species studied had both large eyes and large antennae, " explains Markus Knaden. For their analyses, the researchers reconstructed the primary sensory brain structures that play a role in vision and olfaction, including the optic and antennal lobes. In addition, they used high-resolution microscopy to take a closer look at the sensory organs of the various fly species. "One reason why animals have to choose either a well-developed olfactory system or vision might be that in embryonic development both sensory organs emerge from the same structure with only a limited number of nuclei. The competition for resources, which decides which of the two sensory organs is more pronounced, thus takes place at a very early stage of development," says Bill Hansson, head of the Department of Evolutionary Neuroethology.An important finding of the study is that genetic traits are linked. A change in one trait can have a large impact on the organism. However, some properties are less easy to modify, especially when tethered together with another. "It is fascinating that two senses so well studied, such as vision and olfaction, are inversely correlated. We now suspect that evolutionary pressures exist that are driving insects to prioritize the eye or the nose," says Ian Keesey.With their study, the scientists want to open new avenues in the so-called Eco-Evo-Devo research. This research field is based on the assumption that concepts of ecology (eco), evolution (evo) and developmental biology (devo) are tightly linked, and the understanding of ecological relationships also requires evolutionary and developmental knowledge and vice versa. Although genomic data are available for many species, knowledge of their ecology is often lacking. "These trade-offs, especially in genetic model organisms, provide an avenue for determining the mechanisms for how ecology and evolution shape the natural world," says Ian Keesey.The scientists also want to encourage other research groups not to look only at the well-known
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New Species
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March 12, 2019
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https://www.sciencedaily.com/releases/2019/03/190312092527.htm
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Meet India's starry dwarf frog, lone member of newly discovered ancient lineage
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The starry dwarf frog is an expert hider. Plunging into leaf litter at the slightest disturbance, it has successfully evaded attention for millions of years -- until now.
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The thumbnail-sized species was discovered in India's Western Ghats, one of the world's "hottest" biodiversity hotspots. Scientists have named the frog But "This is an oddball frog -- it has no close sister species for maybe tens of millions of years," said David Blackburn, the associate curator of herpetology at the Florida Museum of Natural History. "With frogs, there are still ancient lineages out there awaiting discovery. This gives us one more puzzle piece to think about deep time."Dark brown with a bright orange underbelly and speckled with pale blue dots, the frog camouflages well in wet leaf litter, and only a few individuals have been found."The coloration was the first thing that stood out to me, these starry patterns with a blue tinge," said Seenapuram Palaniswamy Vijayakumar, lead author of the species description and now a postdoctoral fellow at George Washington University. "We hadn't seen anything like this before."But the starry dwarf frog nearly got overlooked in the crush of new species that Vijayakumar and his then-doctoral supervisor Kartik Shanker were finding on a series of expeditions to the Western Ghats, a 1,000-mile-long mountain range along India's southwestern coast.Vijayakumar and Shanker, associate professor at the Indian Institute of Science, had designed a meticulous study, covering multiple elevations, habitats and hill ranges to record and map the region's frogs, lizards and snakes."When we started sampling, we realized we were digging up a huge treasure," Vijayakumar said. "This was one among 30 species we captured one night, and while I took photos of it, none of us paid much attention to it."The next morning, on a chilly, wet stroll over the grasslands -- watching the ground for leeches -- Vijayakumar spotted another of the unusually patterned frogs."I picked it up and said, 'Hey, this is the same guy I photographed in the night,'" he said. "As a greedy researcher, I kept it, but at that point in time, it wasn't too exciting for me. I didn't realize it would become so interesting."Years passed before Vijayakumar and Shanker could turn their attention to the unknown frog species and assemble a research team to describe it. Alex Pyron, the Robert F. Griggs associate professor of biology at George Washington University and now Vijayakumar's adviser, analyzed the frog's genetics, and Florida Museum associate scientist Edward Stanley CT scanned the frog, revealing its skeleton and other internal features.Thanks to CT technology, the starry dwarf frog could traverse more than 8,700 miles from Pune, India, to Blackburn's computer monitor in Gainesville, Florida, in a matter of minutes."I've never physically seen this species we've put all this effort into describing," Blackburn said. "Once specimens are digitized, it really doesn't matter where they are. The strengths that Ed and I could contribute to the team -- comparative anatomy -- were things we were able to do digitally."Blackburn and Stanley could instantly compare the starry dwarf frog's bone structure to other frog species from the Western Ghats that have been imaged as part of the openVertebrate project, known as oVert, an initiative to scan 20,000 vertebrates from museum collections."We have this deep bench of CT data that makes collections amassed over hundreds of years instantaneously available, not just to researchers, but to anyone with a computer," Stanley said.The team found that "These frogs are relics. They persisted so long. This lineage could have been knocked off at any point in time," Vijayakumar said. "Irrespective of who we are, we should be celebrating the very fact that these things exist."Scientists have found many ancient lineages of frogs in the Western Ghats, whose biodiversity stems from its history and distinct geography. India, once part of Africa, split from Madagascar about 89 million years ago and drifted northeast, eventually colliding with the Asian mainland and giving rise to the Himalayas. But its long isolation as an island provided fertile ground for the evolution of new life forms and may have sheltered species that disappeared elsewhere. This is especially true of the Western Ghats, which is much like a network of islands, Vijayakumar said. The elevated region has been cross-sectioned into separate hill ranges by millions of years of erosion and climatic changes."It's a perfect scenario for cooking up new species," he said.One question he and Blackburn are interested in exploring further is whether peninsular India's frogs are the descendants of African ancestors or whether they first originated in Asia and then moved south.Finding ancient lineages like Astrobatrachinae can help fill in in the region's distant biological past, but the starry dwarf frog maintains many mysteries of its own. Researchers still do not know its life cycle, the sound of its call or whether the species is threatened or endangered.Vijayakumar said when study co-author K.P. Dinesh of the Zoological Society of India returned to the hill range where the frog was first found, "he searched the whole forest floor and hardly saw any individuals. This frog is so secretive. Just one hop into the litter, and it's gone."
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New Species
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March 7, 2019
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https://www.sciencedaily.com/releases/2019/03/190307103114.htm
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Star Wars and Asterix characters amongst 103 beetles new to science from Sulawesi, Indonesia
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The Indonesian island of Sulawesi has been long known for its enigmatic fauna, including the deer-pig (babirusa) and the midget buffalo. However, small insects inhabiting the tropical forests have remained largely unexplored.
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Such is the case for the tiny weevils of the genus "We had found hundreds of species on the neighboring islands of New Guinea, Borneo and Java -- why should Sulawesi with its lush habitats remain an empty space?" asked entomologist and lead author of the study Dr Alexander Riedel, Natural History Museum Karlsruhe (Germany).In fact, Riedel knew better. Back in 1990, during a survey of the fauna living on rainforest foliage in Central Sulawesi, he encountered the first specimens that would become the subject of the present study. Over the next years, a series of additional fieldwork, carried out in collaboration with the Indonesian Institute of Sciences (LIPI), managed to successfully complete the picture."Our survey is not yet complete and possibly we have just scratched the surface. Sulawesi is geologically complex and many areas have never been searched for these small beetles," said Raden Pramesa Narakusumo, curator of beetles at the Museum Zoologicum Bogoriense (MZB), Indonesian Research Center for Biology.Why have all these beetles remained overlooked for so long?Unlike the all-time favourite stag beetles or jewel beetles, tiny beetles that measure no more than 2-3 millimeters seem to have been attracting little interest from entomologists. Their superficial resemblance does not help identification either.In fact, the modern taxonomic approach of DNA sequencing seems to be the only efficient method to diagnose these beetles. However, the capacity for this kind of work in Indonesia is very limited. While substantial evidence points to thousands of undescribed species roaming the forests in the region, there is only one full-time position for a beetle researcher at the only Indonesian Zoological Museum near Jakarta. Therefore, international collaboration is crucial.Coming up with as many as 103 novel names for the newly described species was not a particularly easy task for the researchers either. While some of the weevils were best associated with their localities or characteristic morphology, others received quite curious names.A small greenish and forest-dwelling species was aptly named after the Star Wars character Yoda, while a group of three species were named after Asterix, Obelix and Idefix -- the main characters in the French comics series The Adventures of Asterix. Naturally, Other curious names include Additionally, the names of four of the newly described beetles pay tribute to renowned biologists, including Charles Darwin (father of the Theory of Evolution), Paul D. N. Hebert (implementer of DNA barcoding as a tool in species identification) and Francis H. C. Crick and James D. Watson (discoverers of the structure of DNA).Back in 2016, in another weevil discovery, Dr Alexander Riedel and colleagues described four new species from New Britain (Papua New Guinea), which were also placed in the genus Sulawesi is at the heart of Wallacea, a biogeographic transition zone between the Australian and Asian regions. The researchers assume that To help future taxonomists in their work, in addition to their monograph paper in "This provides a face to the species name, and this is an important prerequisite for future studies on their evolution," explained the researchers."Studies investigating such evolutionary processes depend on names and clear diagnoses of the species. These are now available, at least for the fauna of Sulawesi."
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New Species
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March 4, 2019
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https://www.sciencedaily.com/releases/2019/03/190304182113.htm
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New key players in the methane cycle
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Methane is not only a powerful greenhouse gas, but also a source of energy. Microorganisms therefore use it for their metabolism. They do so much more frequently and in more ways than was previously assumed. Methane is a very special molecule. It is the main component of natural gas and we heat our apartments with it, but when reaching the atmosphere it is a potent greenhouse gas. It is also central in microbiology: In the absence of oxygen, a special group of microorganisms, the so-called methanogenic archaea, can produce methane. Other microorganisms -- archaea living in symbiosis with bacteria -- can use methane as a food source.
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Regardless of whether methane is produced or consumed, the same enzyme is the key: methyl coenzyme M-reductase (MCR). This enzyme produces methane, but it can also be used to break up this gas. This enzyme produces methane and can break this gas up again. For a long time, scientists believed that only a few species of microbes could convert methane in one way or another. Recently, however, increasing evidence has sprung up that important key players in the methane cycle have been overlooked.Scientists from Jiao Tong University in Shanghai, China, and the Max Planck Institute for Marine Microbiology in Bremen have now taken a closer look at this. They scoured global genome databases, in which innumerable information on the genes found in the environment so far is collected, for new methane organisms. Their trick: They did not look for specific organisms, but for the key enzyme.In his search for gene sequences similar to the known MCR genes, first author Yinzhao Wang from Jiao Tong University soon found what he was looking for. He discovered a number of previously unknown genes that carry the necessary information for the production of MCR. "These MCRs can be roughly divided into three groups," says Yinzhao Wang. "One group comprises the known gene sequences. The other two groups are completely new." The researchers used these new sequences as the first piece of the puzzle to bin complete genomes from the vast amount of data available. The results were stunning: The assembled genomes were completely different from those of known methane microbes. "For example, we found MCR in Archaeoglobi and in archaea from the TACK superphylum. Such metabolic pathways have not previously been suspected in these organisms," says Fengping Wang from Jiao Tong University, the initiator of the study.The results now published show that different variants of the methane metabolism are widespread in archaea. This suggests a greater importance of these microorganisms in global carbon balancing than previously assumed.What the microbes do with these metabolic pathways in detail has not yet been clarified. Some organisms seem to produce methane. Others, on the other hand, seem to oxidize it. "Our results are very exciting! We presumably discovered the first archaea that can breathe methane with sulfate without partner bacteria," says Gunter Wegener from the Max Planck Institute in Bremen. "Others obviously don't feed on methane, but on higher hydrocarbons." The genomes alone only provide clues to the way of life of these archaea. "We often do not know in which direction the organisms use the apparently very flexible metabolic pathway of methane production," Wegener continues.In order to understand exactly what the discovered organisms are doing and to test the genome-based hypotheses, the researchers from Bremen and Shanghai will now jointly try to cultivate these organisms (i.e. grow them in the laboratory). It's not that easy though -- they seem to prefer life in hot springs and in deep subsurface habitats. With material from these places, the scientists will begin their cultivation experiments.
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New Species
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March 4, 2019
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https://www.sciencedaily.com/releases/2019/03/190304121457.htm
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New portal of entry for influenza viruses
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Researchers from the Medical Center -- University of Freiburg and the University of Zurich have discovered an entirely new infection route for influenza A viruses. While all previously known influenza A viruses bind sialic acid moieties on the host cell surface, the recently discovered bat-derived influenza A virus subtypes infect human and animal cells by utilizing MHC class II proteins. The immunologically relevant MHC class II molecules are ubiquitously found in many animal species, which is why the discovery will play an important role in assessing the risk of spill-over infections to other species than bats. The study, published on 20 February 2019 in the journal
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"In the lab, bat viruses can use the MHC class II complexes of mice, pigs, chickens, or humans to enter the cell. It is thus not unlikely that these bat-derived influenza viruses could be transmitted naturally from bats to other vertebrates and even humans," says Prof. Dr. Martin Schwemmle, study and research group leader at the Institute of Virology at the University Medical Center Freiburg.With a two-pronged strategy and a lot of effort, the researchers from Freiburg and Zurich finally succeeded in finding the cellular factor mediating the virus's entry into the host cell. First, the group of Prof. Dr. Silke Sterz from the Institute of Medical Virology of the University of Zurich compared the proteins produced in infectible cells to those produced in non-infectible cells. Using a technique called transcriptomic profiling, the researchers estimated the amount of cellular proteins via mRNA copies. This approach already provided strong indications for the MHC class II complex as the receptor candidate. Then, the team from Freiburg led by Prof. Schwemmle conducted a screening experiment in which they cut one of a total of 20,000 genes in single cells using the molecular scissor CRISPR-Cas. "Cells in which we switched off MHC class II were immune to infection. That was the final proof that the virus enters the cell with the help of MHC class II molecules," says the virologist.The discovery of this second, sialic acid-independent, mechanism also raises the question which strategy was first in evolutionary terms. "It is quite possible that the newly discovered route of infection via MHC class II originates from the already known sialic acid pathway," says Prof. Schwemmle. The current study also raises new research questions: Are there other influenza viruses that use MHC class II proteins as host cell receptor? How simple can influenza viruses switch their receptors, and is it even possible that influenza viruses emerge, which can infect target cells by both receptors? "These are all questions that we now aiming to investigate, because influenza viruses are evidently more versatile than previously thought," says the virologist Prof. Schwemmle.
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New Species
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February 28, 2019
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https://www.sciencedaily.com/releases/2019/02/190228075552.htm
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New species of 'golden death' bacterium digests parasitic worms from the inside out
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A new species of bacterium,
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Professor Antony Page, University of Glasgow, the corresponding author said: "Nematodes, commonly called roundworms, cause serious chronic diseases in animals and are particularly common in grazing livestock. Some nematodes, such as hookworms, also infect humans. These parasites have developmental stages that naturally feed on bacteria before they infect the final host. This study describes a newly discovered bacterial species, called The researchers isolated two new bacterial strains -- JUb129 and JUb275 -- from free-living roundworms found on a rotten apple in Paris, France, and a rotten fig in Bangalore, India. In laboratory experiments, the researchers fed the bacteria, which produce yellow mucoid colonies that have a pungent odor, to larvae of the nematode worm The authors observed that the To investigate which genes might be involved in conferring the nematode-killing ability of The authors tested Professor Page said: "Nematode parasites are very common, cause disease and have an economic impact on livestock rearing. They are mainly controlled by a limited group of drugs called anthelmintics, which are becoming less effective as worms are becoming resistant to many of these drugs. Our findings raise the possibility that
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New Species
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February 27, 2019
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https://www.sciencedaily.com/releases/2019/02/190227142731.htm
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A rare assemblage of sharks and rays from nearshore environments of Eocene Madagascar
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Eocene-aged sediments of Madagascar contain a previously unknown fauna of sharks and rays, according to a study released February 27, 2019 in the open-access journal
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The Mahajanga basin of northwestern Madagascar yields abundant fossil remains of terrestrial and marine ecosystems, but little is known about fossil sharks and rays during the Eocene Epoch, 55-34 million years ago, in this region. This is in contrast to the numerous shark and ray faunas known from other Eocene sites around the globe, and to shark and ray ecosystems known from older and younger sediments in the Mahajanga basin.In this study, Samonds and colleagues collected isolated teeth, dental plates, and stingray spines from ancient coastal sediments of the Ampazony and Katsepy regions of the basin, dated to the middle to late Eocene. They identified at least 10 species of sharks and rays, including one new species, Carcharhinus underwoodi. This is the oldest named species of Carcharhinus, a genus that has been globally distributed for the past 35 million years but is known only rarely from the Eocene.Aside from the new species, the fauna of Eocene Madagascar shares many species with Eocene ecosystems across North Africa, suggesting these animals were widespread in southern seas at that time. On the other hand, the Madagascar fauna is uniquely lacking in sandsharks and dominated by eagle rays, indicating a somewhat unusual ecosystem, unsurprising given Madagascar's long history of isolation. The authors caution that this study provides an incomplete picture given that they collected only fossils larger than 2 millimeters. They recommend that future studies target smaller material for a more complete view of the ancient ecosystem.
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New Species
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February 27, 2019
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https://www.sciencedaily.com/releases/2019/02/190227124851.htm
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How fungi influence global plant colonization
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The symbiosis of plants and fungi has a great influence on the worldwide spread of plant species. In some cases, it even acts like a filter. This has been discovered by an international team of researchers with participation from the University of Göttingen. The results appeared in the journal
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In the colonisation of islands by plant species, it isn't just factors like island size, isolation and geological development that play an important role, but also the interactions between species. The scientists found that the symbiosis of plant and fungus -- the mycorrhiza -- is of particular importance. The two organisms exchange nutrients via the plant's fine root system: the fungus receives carbohydrates from the plant; the plant receives nutrients that the fungus has absorbed from the soil."For the first time, new data on the worldwide distribution of plant species in 1,100 island and mainland regions allows us to investigate the influence of this interaction on a global scale," says Dr Patrick Weigelt from the University of Göttingen's Department of Biodiversity, Macroecology and Biogeography, who worked on the study. The results: mycorrhiza-plant interactions, which are naturally less frequent on islands because the two organisms rely on each other, mean that the colonisation of remote islands is hindered. The lack of this symbiotic relationship may act like a brake on the spread of the plants. This is not the case for plant species introduced by humans, as fungi and plants are often introduced together. Head of Department, Professor Holger Kreft, adds, "The proportion of plant species with mycorrhiza interactions also increases from the poles to the equator." One of the most prominent biogeographic patterns, the increase in the number of species from the poles to the tropics, is closely related to this symbiosis.Dr Camille Delavaux, lead author from the University of Kansas (US), explains, "We show that the plant symbiotic association with mycorrhizal fungi is an overlooked driver of global plant biogeographic patterns. This has important consequences for our understanding of contemporary island biogeography and human-mediated plant invasions." The results show that complex relationships between different organisms are crucial for understanding global diversity patterns and preserving biological diversity. "The absence of an interaction partner can disrupt ecosystems and make them more susceptible to biological invasions," Weigelt stresses.
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New Species
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February 27, 2019
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https://www.sciencedaily.com/releases/2019/02/190227111118.htm
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New buzz around insect DNA analysis and biodiversity estimates
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In the face of declining numbers of insects across the globe, scientists continue to expand our knowledge about invertebrate organisms and their biodiversity across the globe. Insects are the most abundant animals on planet Earth -- they outweigh all humanity by a factor of 17. Their abundance, variety, and ubiquity mean insects play a foundational role in food webs and ecosystems, from the bees that pollinate the flowers of food crops to the termites that recycle dead trees. With insect populations dwindling worldwide, there are still new species being discovered.
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Researchers on the remote forested island of Hauturu, New Zealand (also known as Little Barrier Island) have compiled a staggering inventory of invertebrate biodiversity using DNA sequencing, adding a significant number of invertebrates to GenBank -- an open access database of all publicly available DNA sequences. The results are published this week in the Ecological Society of America's journal The number of invertebrate species that exist globally is uncertain, and it is difficult to characterize entire invertebrate communities using traditional methods that require the examination of individual specimens by an expert taxonomist.This is where DNA sequencing comes in. This method is hailed as a tool for resolving the biodiversity of earth's underexplored ecosystems. It allows for the identification of invertebrate specimens based on more efficient molecular analysis.Andrew Dopheide -- a researcher at the University of Auckland -- and colleagues employed a combination of old-school field biology with next-generation DNA sequencing to explore the use of combined datasets as a basis for estimating total invertebrate biodiversity on Hauturu island. They collected specimens from leaf litter samples, pitfall traps, and the soil itself."In a New Zealand context, we are not aware of any other ecosystem-wide DNA-based surveys of terrestrial invertebrate biodiversity on this scale," explained Dopheide. "Additionally, there was no information about invertebrate biodiversity on Hauturu, despite this being one of New Zealand's most pristine and important natural ecosystems."At the end of the study, they estimated that the above-ground community of invertebrates includes over 1000 arthropod species (having an exoskeleton, a segmented body, and paired jointed appendages), of which 770 are insects, and 344 are beetles.The soil they sequenced yielded even richer samples. Soils are a promising substrate for DNA analyses of biodiversity because they contain diverse communities of organisms as well as biological debris including DNA molecules. Scientists know much less about soil communities than about above-ground communities.From the soil samples they were able to estimate 6856 arthropod species (excluding mites), of which almost 4000 are insects.Beetles (order Coleoptera) were most abundant, followed by sawflies, wasps, bees and ants (order Hymenoptera), flies (Diptera), butterflies and moths (Lepidoptera), and various Amphipoda -- a diverse order of small, shrimp-like crustaceans that mostly occur in the ocean, but also in freshwater and some terrestrial habitats.In total, they added over 2500 new DNA sequences to GenBank, which houses data from more than 100,000 distinct organisms, and has become an important database for research in biological fields."We were surprised that so few of the invertebrates were already represented in GenBank," said Dopheide, "which suggested that we had recovered mostly new or little-studied species despite using very traditional collection methods, and emphasized the lack of knowledge about these important organisms... It's likely that many of the invertebrates without DNA sequences in GenBank are indeed new species, but we don't know for sure."With insect populations dwindling worldwide, at least there are still new species being sequenced and documented. This work by Dopheide et al. has marked the trail, and set the bar, for mixing old-school natural science with DNA sequencing to characterize species that dominate the structure and function of ecosystems... while marveling at how many of them are beetles.
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New Species
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February 25, 2019
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https://www.sciencedaily.com/releases/2019/02/190225105106.htm
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Spring migration is now earlier in European and North American birds
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The greatest advances were found among short-distance migrants that winter in Europe or North America: about 1.5-2 days per decade. Long-distance migrants that winter in the tropics have also advanced the start of their migration, but only by approximately 0.6-1.2 days per decade.
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"Based on changes in median migration dates, birds have on average advanced their spring migration by a little over a week since the late 1950s," says Aleksi Lehikoinen from the Finnish Museum of Natural History, University of Helsinki.Some species show much greater advances. For instance, Whooper Swans now arrive in Finland about two weeks earlier than in the 1980s.The advances in spring migration dates are not equal across the migration season. Early migrants of a given species have advanced their migration dates more than late migrants within the species' migration season. First migrants have the highest pressure to arrive at their breeding grounds as early as possible, whereas late migrants are typically non-breeders, which have no rush to move north. This asymmetry has led to an overall increase in the duration of migration.Annual arrival dates of bird species were explained by local temperatures: the earlier the spring, the earlier the timing of migration and the longer the migration season. Geographical differences in climate change also explained regional differences in the advancement of spring migration."Birds advanced their migration dates more in Europe than in Canada, because spring temperatures have risen more quickly in Europe," says Andreas Lindén from Yrkeshögskolan Novia, Finland.The study is based on long-term monitoring data from 21 North European and Canadian bird observatories and included almost 200 study species. The longest time series started in 1959 and the early 1960s and a large part of the data was collected by volunteer birdwatchers. The results were published in the international journal
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New Species
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February 22, 2019
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https://www.sciencedaily.com/releases/2019/02/190222101235.htm
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Studying species interactions using remote camera traps
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Species are often involved in complex interactions with other species, which can affect their occurrence, abundance, feeding habits and disease transmission. Observing and studying species interactions can be difficult. To circumvent this problem, ecologists increasingly rely on remote devices such as camera traps. In a recent study carried out by researchers from the Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) in Germany and University of California, Davis, USA, the scientists explored to what extent camera trap data are suitable to assess subtle species interactions such as avoidance in space and time. The study is published in the international journal
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Species interact in numerous ways. In mammals, many interactions are detrimental for at least one of the species, such as cases of predation or disease transmission. In such cases, a species (say, a prey) may choose to avoid encounters with a second species (say, a predator). The researchers focussed on two situations: spatiotemporal avoidance, where the prey avoids its predator simply by going somewhere else, and temporal segregation, where the prey avoids being present in the same location as its predator by being active at times when the predator is not.The aim of the current study was to create a framework that researchers worldwide could use to detect interactions between species based on their own camera trap data. The scientists used computer simulations to find out how camera-trap data can best be used to study such species interactions. "Identifying which statistical tool is the most sensitive was one of the main goals of our work, as we are aware how challenging it can be to collect large datasets under natural conditions, even with camera traps," explains Dr Alexandre Courtiol, one of the leading Leibniz-IZW scientists on this project. The proposed approach should allow other scientists to determine which statistical method to use and how many records they need to best understand species interactions for their specific field study. "We show that for many realistic scenarios many records are needed to produce trustworthy results, but I am optimistic: we can achieve this by standardizing data collection and combining datasets from multiple studies. In short, we must collaborate," Courtiol adds.
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New Species
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February 20, 2019
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https://www.sciencedaily.com/releases/2019/02/190220133534.htm
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Bat influenza viruses could infect humans
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Bats don't only carry the deadly Ebola virus, but are also a reservoir for a new type of influenza virus. These newly discovered flu viruses could potentially also attack the cells of humans and livestock, researchers at the University of Zurich have now shown.
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Seasonal outbreaks of the flu are caused by influenza viruses that can only infect people. Influenza types that circulate in birds or pigs are normally not a threat to humans. However, in rare cases an avian or pig virus can pass on to humans -- a process called zoonotic transmission -- which at worst can lead to a global influenza pandemic with numerous serious illnesses and deaths.About six years ago, a new kind of influenza virus was discovered in bats in South America. The flying mammals have been the focus of virologists for a long time already. This is because they carry many different kinds of viruses, including lethal ones such as the Ebola virus. However, it has previously been unclear whether bat influenza viruses also present a threat to humans. An international research team led by the University of Zurich (UZH) has now discovered that these new influenza viruses have the potential to also infect humans and livestock.Previously known influenza viruses bind to host cells via sialic acids. These groups of chemicals can be found on the surface of almost all human cells and in various animals. This is one of the reasons why influenza viruses can infect species that are very different from one another, such as ducks, chickens, pigs and humans. Unlike these viruses, the bat influenza viruses don't bind to sialic acids, which is why several research teams all over the world started searching for the receptor through which they enter human cells.Silke Stertz and her team at the Institute of Medical Virology at UZH have now been able to identify this "entry gate." "The influenza viruses use MHC-II molecules to enter the host cell," says the head of the study. These protein complexes are normally located on the surface of certain immune cells, and their role is to distinguish between the body's own cells and structures and those that are foreign. A few other virus types also enter cells in this way."What surprised us is that bat influenza viruses can not only use the MHC-II complexes of human cells, but also those of chickens, pigs, mice and several bat species," explains UZH PhD candidate Umut Karakus, first author of the study. The influenza viruses of bats thus have the potential to infect both humans as well as livestock, at least at the level of entering cells. "Such an infection has not yet been observed. However, our findings show that the viruses generally have this zoonotic potential," adds Silke Stertz. This is reason enough for the UZH virologist to continue researching the potentially dangerous viruses, not least since due to migration and travel the problem is not restricted to South America.
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New Species
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February 19, 2019
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https://www.sciencedaily.com/releases/2019/02/190219132918.htm
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Marsupial lived among Arctic dinosaurs
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A research team has discovered a previously unknown species of marsupial that lived in Alaska's Arctic during the era of dinosaurs, adding a vivid new detail to a complex ancient landscape.
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The thumb-sized animal, named The discovery adds to the picture of an environment that scientists say was surprisingly diverse. The tiny animal, which is the northernmost marsupial ever discovered, lived among a unique variety of dinosaurs, plants and other animals.Alaska's North Slope, which was at about 80 degrees north latitude when Finding a new marsupial species in the far north adds a new layer to that evolving view, said Patrick Druckenmiller, the director of the University of Alaska Museum of the North."Northern Alaska was not only inhabited by a wide variety of dinosaurs, but in fact we're finding there were also new species of mammals that helped to fill out the ecology," said Druckenmiller, who has studied dinosaurs in the region for more than a decade. "With every new species, we paint a new picture of this ancient polar landscape."Marsupials are a type of mammal that carries underdeveloped offspring in a pouch. Kangaroos and koalas are the best-known modern marsupials. Ancient relatives were much smaller during the late Cretaceous, Druckenmiller said. The research team, whose project was funded with a National Science Foundation grant, identified the new marsupial using a painstaking process. With the help of numerous graduate and undergraduate students, they collected, washed and screened ancient river sediment collected on the North Slope and then carefully inspected it under a microscope. Over many years, they were able to locate numerous fossilized teeth roughly the size of a grain of sand."I liken it to searching for proverbial needles in haystacks -- more rocks than fossils," said Florida State University paleobiologist Gregory Erickson, who contributed to the paper.Jaelyn Eberle, curator of fossil vertebrates at the University of Colorado Museum of Natural History, led the effort to examine those teeth and a few tiny jawbones. Their analysis revealed a new species and genus of marsupial.Mammal teeth have unique cusps that differ from species to species, making them a bit like fingerprints for long-dead organisms, said Eberle, the lead author of the study."If I were to go down to the Denver Zoo and crank open the mouth of a lion and look in -- which I don't recommend -- I could tell you its genus and probably its species based only on its cheek teeth," Eberle said.The name Other co-authors of the
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New Species
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February 14, 2019
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https://www.sciencedaily.com/releases/2019/02/190214115535.htm
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Aloe sanginalis, a new red Aloe from Somaliland
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<em>Aloe sanguinalis</em>
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It remains a mystery how this beautiful and showy aloe species has remained undescribed by science for so long, but one of the theory is that the plant was 'hiding in plain sight"' in an area not usually known for its hight biological diversity.The locals in the area have long known that the plants were different from other kinds of "Dacar," (the Somali name for Aloes) in the region and were referring to them as "Dacar cas" or "Red aloe."Similarly, the scientific name for the new species -- The story of the formal recognition of "Dacar cas" or Later on, when the plant came to the attention of Mary Barkworth, a botanist interested in building botanical capacity in Somaliland. After listening to Ahmed, the two of them began looking formally into the possibility that "Dacar cas" was, indeed, an undescribed species. They were soon convinced it was. After the initial excitement, the next step required demonstrating that "Dacar Cas" differs from all the other 600+ known species of Aloe. That step took longer, but finally it has been done."This news comes from a region which had experienced periods of conflict and instability, climate change effects and accelerated environmental degradation, whereby much of the people's attention has been focused on promoting livelihoods and resilience. With this positive piece of information we hope that we inspire scientists to further explore the area," explains Dr Barkworth.The new species is currently known from only two locations, but it is hoped that naming and sharing pictures of it online will encourage discovery and documentation of additional locations.
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New Species
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February 12, 2019
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https://www.sciencedaily.com/releases/2019/02/190212141406.htm
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New frog species found on remote Ethiopian mountain
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In summer 2018, NYU Abu Dhabi Postdoctoral Associates Sandra Goutte and Jacobo Reyes-Velasco explored an isolated mountain in southwestern Ethiopia where some of the last primary forest of the country remains. Bibita Mountain was under the radars of the team for several years due to its isolation and because no other zoologist had ever explored it before.
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"Untouched, isolated, and unexplored: it had all the elements to spike our interest," says Dr. Reyes-Velasco, who initiated the exploration of the mountain. "We tried to reach Bibita in a previous expedition in 2016 without success. Last summer, we used a different route that brought us to higher elevation," he added.Their paper, published in Back in NYU Abu Dhabi, the research team sequenced tissue samples from the new species and discovered that "The discovery of such a genetically distinct species in only a couple of days in this mountain is the perfect demonstration of how important it is to assess the biodiversity of this type of places. The Bibita Mountain probably has many more unknown species that await our discovery; it is essential for biologists to discover them in order to protect them and their habitat properly," explains NYU Abu Dhabi Program Head of Biology and the paper's lead researcher Stéphane Boissinot, who has been working on Ethiopian frogs since 2010.
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New Species
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February 12, 2019
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https://www.sciencedaily.com/releases/2019/02/190212104707.htm
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Cancer comparison across species highlights new drug targets
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Cancer genes in mucosal melanoma, a rare and poorly understood subtype of melanoma, have been compared in humans, dogs and horses for the first time by scientists at the Wellcome Sanger Institute and their collaborators. Researchers sequenced the genomes of the same cancer across different species to pin-point key cancer genes.
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The results, reported in Mucosal melanoma is a rare form of melanoma, a tumour type usually associated with skin cancer. Of the 15,400 people diagnosed with melanoma in the UK each year*, around 1 per cent will be diagnosed with mucosal melanoma.The cancer arises from the cells that produce pigment, known as melanocytes, which are found not only in the skin but also mucosal surfaces of the body, such as the sinuses, nasal passages, mouth, vagina and anus.The risk factors for mucosal melanoma are unknown, and there is no known link to UV exposure or family history. Patients with the cancer often present late in the progression of the disease, and the main treatment for mucosal melanoma is surgical removal of the tumour. As well as humans, the cancer affects dogs and horses with varying outcomes for the different species.To uncover the genetics underpinning the cancer, researchers at the Sanger Institute and their collaborators sequenced the genomes of mucosal melanoma tumours taken from human, canine and equine patients that had been diagnosed with the disease.Analysing the genomic data from 46 human, 65 canine and 28 equine melanoma tumours, all at the primary stage of cancer, scientists revealed a handful of genes that were mutated in all species.Dr David Adams, corresponding author from the Wellcome Sanger Institute, said: "Genomics gives us a unique view into the hidden similarities and differences of cancer between species. The genetic changes, or mutations, we found in mucosal melanoma tumours across humans, dogs and horses suggests they are important enough to be conserved between species. These key mutations are likely to drive the cancer and could be targets for the development of new drugs."Immunotherapy, the stimulation of the body's own immune system to attack cancer cells, has been used to treat some people with melanoma, but has not been effective for people with the subtype, mucosal melanoma, and the reason was unknown. Researchers now suggest that unlike skin melanoma, mucosal melanoma tumours carry few mutations so they remain 'hidden' to the immune system and do not spark the immune response needed to target the cancer.Kim Wong, first author from the Wellcome Sanger Institute, said: "Understanding the genetic changes underpinning mucosal melanoma suggests why people with this particular type of cancer may not benefit from immunotherapies. Genomics can help identify who is at greater risk of developing mucosal melanoma and provide information to genetic counsellors and doctors advising patients on disease management."This study is the first to sequence horse tumours, and the first genomic experiment of this scale on dog tumours. Grey horses are genetically predisposed to getting melanoma. However, the cancer is very different in horses as it does not usually spread, unlike the disease in humans and dogs.Professor Geoffrey Wood, from the University of Guelph in Canada, said: "Spontaneous tumours in dogs are gaining recognition as 'models' of human cancers for the development of therapies that can benefit both species. This study shows the importance of understanding the genetic similarities and differences of cancers across species so that the most biologically relevant drug targets are prioritized."
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New Species
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February 12, 2019
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https://www.sciencedaily.com/releases/2019/02/190212104658.htm
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New tarantula species from Angola distinct with a one-of-a-kind 'horn' on its back
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A new to science species of tarantula with a peculiar horn-like protuberance sticking out of its back was recently identified from Angola, a largely underexplored country located at the intersection of several Afrotropical ecoregions.
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Collected as part of the National Geographic Okavango Wilderness Project, which aims to uncover the undersampled biodiversity in the entire Okavango catchment of Angola, Namibia and Botswana, thereby paving the way for sustainable conservation in the area, the new arachnid is described in a paper published in the open-access journal Although the new spider (The new tarantula's extraordinary morphology has also prompted its species name: "No other spider in the world possesses a similar foveal protuberance," comment the authors of the paper.During a series of surveys between 2015 and 2016, the researchers collected several female specimens from the miombo forests of central Angola. To find them, the team would normally spend the day locating burrows, often hidden among grass tufts, but sometimes found in open sand, and excavate specimens during the night. Interestingly, whenever the researchers placed an object in the burrow, the spiders were quick and eager to attack it.The indigenous people in the region provided additional information about the biology and lifestyle of the baboon spider. While undescribed and unknown to the experts until very recently, the arachnid has long been going by the name "chandachuly" among the local tribes. Thanks to their reports, information about the animal's behaviour could also be noted. The tarantula tends to prey on insects and the females can be seen enlarging already existing burrows rather than digging their own. Also, the venom of the newly described species is said to not be dangerous to humans, even though there have been some fatalities caused by infected bites gone untreated due to poor medical access.In conclusion, the researchers note that the discovery of the novel baboon spider from Angola does not only extend substantially the known distributional range of the genus, but can also serve as further evidence of the hugely unreported endemic fauna of the country:"The general paucity of biodiversity data for Angola is clearly illustrated by this example with theraphosid spiders, highlighting the importance of collecting specimens in biodiversity frontiers."Apart from the described species, the survey produced specimens of two other potentially new to science species and range expansions for other genera. However, the available material is so far insufficient to formally diagnose and describe them.
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New Species
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February 11, 2019
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https://www.sciencedaily.com/releases/2019/02/190211182850.htm
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Almost 2,000 unknown bacteria discovered in the human gut
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Researchers at EMBL's European Bioinformatics Institute and the Wellcome Sanger Institute have identified almost 2000 bacterial species living in the human gut. These species are yet to be cultured in the lab. The team used a range of computational methods to analyse samples from individuals worldwide.
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The results, published in the journal The human gut is home to many species of microbes, collectively referred to as the gut microbiota. Despite extensive studies in the field, researchers are still working on identifying the individual microbial species that live in our guts and understanding what roles they play in human health.There are many reasons why some microbial species that are part of the gut microbiota have remained unknown for so long, such as a low abundance in the gut or an inability to survive outside it. By using computational methods, researchers were able to reconstruct the genomes of these bacteria."Computational methods allow us to understand bacteria that we cannot yet culture in the lab. Using metagenomics to reconstruct bacterial genomes is a bit like reconstructing hundreds of puzzles after mixing all the pieces together, without knowing what the final image is meant to look like, and after completely removing a few pieces from the mix just to make it that bit harder," says Rob Finn, Group Leader at EMBL-EBI. "Researchers are now at a stage where they can use a range of computational tools to complement and sometimes guide lab work, in order to uncover new insights into the human gut."The research highlighted how the composition of gut bacteria differs around the world, and how important it is for the samples that we study to reflect this diversity."We are seeing a lot of the same bacterial species crop up in the data from European and North American populations," continues Finn. "However, the few South American and African datasets we had access to for this study revealed significant diversity not present in the former populations. This suggests that collecting data from underrepresented populations is essential if we want to achieve a truly comprehensive picture of the composition of the human gut.""Computational methods allow us to get an idea of the many bacterial species that live in the human gut, how they evolved and what kind of roles they may play within their microbial community," says Alexandre Almeida, Postdoctoral Fellow at EMBL-EBI and the Wellcome Sanger Institute. "In this study, we leveraged the most comprehensive public databases of gastrointestinal bacteria to identify bacterial species that have not been seen before. The analysis methods we used are highly reproducible and can be applied to larger, more diverse datasets in the future, enabling further discovery.""Research such as this is helping us create a so-called blueprint of the human gut, which in the future could help us understand human health and disease better and could even guide diagnosis and treatment of gastrointestinal diseases," concludes Trevor Lawley, Group Leader at the Wellcome Sanger Institute.
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New Species
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February 11, 2019
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https://www.sciencedaily.com/releases/2019/02/190211131449.htm
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Brazil-endemic plant genus Mcvaughia highlights diversity in a unique biome
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A new species of the Brazil-endemic small genus
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In fact, Seasonally Dry Tropical Forests have only been recognized as a worldwide biome recently and taxonomic studies focusing on its endemic plant species are imperative for conservation management.In their newly published monograph, the team of scientists from Universidade Federal de Minas Gerais, Universidade Federal de Viçosa, Universidade Federal do Amazonas, Universidad Nacional Autónoma de México & Smithsonian answer the need for a deeper understanding on this unique biome, starting with genus "We are truly fascinated by the members of this new and exciting biome and when during a visit in Brazilian herbaria, we found a third species of The name of the newly described species "The results presented in this study are the second step towards a complete taxonomic revision of the Mcvaughioid clade using several additional methods in biosystematics. The macro and micromorphological data presented here are promising for future taxonomic and phylogenetic studies focusing on understanding the morphological evolution in the Mcvaughioid clade, and in Malpighiaceae, as well," conclude the authors.
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New Species
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February 7, 2019
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https://www.sciencedaily.com/releases/2019/02/190207150030.htm
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Seafood mislabelling persistent throughout supply chain, study finds
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Not only does Canada continue to have a problem with fish mislabelling, but that problem persists throughout the supply chain, according to a first-ever study by University of Guelph researchers.
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In a new study, U of G researchers found 32 per cent of fish were mislabelled and the number of incorrectly identified samples became compounded as the samples moved through the food system."We've been doing seafood fraud studies for a decade," said Prof. Robert Hanner, lead author and associate director for the Canadian Barcode of Life Network. "We know there are problems. But this is the first study to move beyond that and look at where the problems are happening throughout the food supply chain."The findings reveal that mislabelling happens before fish are imported into Canada, as well as throughout the supply chain, Hanner added."It seems it's not isolated to foreign markets, but it's also happening at home. The Canadian Food Inspection Agency (CFIA) has partnered with us to actively find solutions to this persistent problem," said Hanner.Published recently in the journal Hanner is the associate Director for the Canadian Barcode of Life Network, headquartered at the Biodiversity Institute of Ontario, University of Guelph."As a science-based regulator, the CFIA works with an array of partners to address mislabelling and promote compliance within industry," said the CFIA's Deputy Chief Food Safety Office, Dr. Aline Dimitri. "It is only through our collective efforts that we will be able to tackle this global issue."U of G researchers examined 203 samples from 12 key targeted species collected from various importers, processing plants and retailers in Ontario. Of the samples, 141 (69.5 per cent) were from retailers, 51 (25 per cent) from importers and 11 (5.5 per cent) from processing plants.Researchers identified the samples using DNA barcoding. Developed at U of G, DNA barcoding allows scientists to determine species of organisms using a short, standardized region of genetic material.The findings revealed 32 per cent of the samples overall were mislabelled. The mislabelling rate was 17.6 per cent at the import stage, 27.3 per cent at processing plants and 38.1 per cent at retailers."The higher mislabelling rate in samples collected from retailers, compared to that for samples collected from importers, indicates the role of distribution and repackaging in seafood mislabelling," said Hanner.He points to a few reasons for the problem."It's either economically motivated, meaning cheaper fish are being purposely mislabelled as more expensive fish. Or it's inconsistent labelling regulations between countries and the use of broader common names being used to label fish instead of scientific species names that are leading to mislabelling."In both Canada and the U.S., fish are labelled using a common name rather than a specific scientific name. For example, a variety of species may be sold as tuna, although different species can significantly vary in price."It creates ambiguity and opens the door for fraud or honest mistakes," he said. "It also makes it more difficult to track species at risk or indicate if a fish is a species that has higher mercury content. At the end of the day, Canadian consumers don't really know what type of fish they are eating."European countries that recently included species names along with common names have seen less fraud, he added.That might help curb the problem with fish imports, Hanner said, but this new study shows a need for verification testing at multiple points along the supply chain."The next step would be to follow one package from import to wholesale to retail and see what happens."
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New Species
| 2,019 |
February 7, 2019
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https://www.sciencedaily.com/releases/2019/02/190207142148.htm
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Butterflies are genetically wired to choose a mate that looks just like them
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Male butterflies have genes which give them a sexual preference for a partner with a similar appearance to themselves, according to new research. In a study publishing February 7th in the open-access journal
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This is one of the first ever genome studies to look at butterfly behavior and it unlocks the secrets of evolution to help explain how new species are formed. The scientists sequenced the DNA from two different species of Heliconius butterflies which live either side of the Andes mountains in Colombia. Heliconians have evolved to produce their own cyanide which makes them highly poisonous and they have distinct and brightly colored wings which act as a warning to would-be predators.Professor Chris Jiggins of the University of Cambridge, one of the lead authors on the paper, said: "There has previously been lots of research done on finding genes for things like color patterns on the butterfly wing, but it's been more difficult to locate the genes that underlie changes in behavior."What we found was surprisingly simple -- three regions of the genome explain a lot of their behaviors. There's a small region of the genome that has some very big effects."The male butterflies were introduced to female butterflies of two species and were scored for their levels of sexual interest directed towards each. The scientists rated each session based on the number of minutes of courtship by the male -- shown by sustained hovering near or actively chasing the females.Unlike many butterflies which use scented chemical signals to identify a mate, Heliconians use their long-range vision to locate the females, which is why it's important each species has distinct wing markings.When a hybrid between the two species was introduced, the male would most commonly show a preference for a mate with similar markings to itself. The research showed the same area of the genome that controlled the coloration of the wings was responsible for defining a sexual preference for those same wing patterns.Dr Richard Merrill, one of the authors of the paper, based at Ludwig-Maximilians-Universität, Munich, said: "It explains why hybrid butterflies are so rare -- there is a strong genetic preference for similar partners which mostly stops inter-species breeding. This genetic structure promotes long-term evolution of new species by reducing intermixing with others."The paper is one of two publishing together in Dr Simon Martin, one of the authors of the second paper, from the University of Edinburgh, explained: "Over a million years a very small number of hybrids in a generation is enough to significantly reshape the genomes of these butterflies."Despite this genetic mixing, the distinct appearance and behaviors of the two species remain intact, and have not become blended. The researchers found that there are many areas of the genome that define each species, and these are maintained by natural selection, which weeds out the foreign genes. In particular, the part of the genome that defines the sex of the butterflies is protected from the effects of inter-species mating.As with the genetics that control mating behavior, these genes enable each butterfly type to maintain its distinctiveness and help ensure long-term survival of the species.But can the findings translate into other species, including humans? Professor Jiggins said: "In terms of behavior, humans are unique in their capacity for learning and cultural changes, but our behavior is also influenced by our genes. Studies of simpler organisms such as butterflies can shed light on how our own behavior has evolved. Some of the patterns of gene sharing we see between the butterflies have also been documented in comparisons of the human and Neanderthal genomes, so there is another link to our own evolution.""Next we would like to know how novel behavior can arise and what kind of genetic changes you need to alter behavior. We already know that you can make different wing patterns by editing the genes. These studies suggest that potentially new behaviors could come about by putting different genes together in new combinations."
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New Species
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February 6, 2019
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https://www.sciencedaily.com/releases/2019/02/190206200401.htm
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Six new species of hideously adorable tentacle-nosed catfish discovered in Amazon
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No one knows just how many species live in the Amazon rainforest -- scientists estimate that it's home to one-third of the world's animal and plant species. There are still thousands out there waiting to be discovered -- like these six new catfish with faces covered in tentacles.
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"We discovered six new species of really cool catfish from the Amazon and Orinoco River basins. They have tentacles on their snouts, they have spines that stick out from their heads, almost like claws, to protect themselves and their nests, and their body is covered with bony plates like armor," says Lesley de Souza, a conservation scientist and ichthyologist at Chicago's Field Museum and lead author of a paper in The new catfish are all members of the genus Some of the new species' names hint at the animals' traits or the story of their discovery. For instance, The catfish are found in northeastern South America, in an area of Venezuela, Colombia, and Guyana known as the Guiana Shield. The fish live in clear, fast-moving rivers and streams. "If you're in the right habitat, you're going to find a lot of them," says de Souza, who co-authored the Threats to the fishes' habitat include large-scale agriculture, deforestation and gold mining. "Miners dredge up the river bottom causing increased sediment load, this changes the habitat structure of the river system, thus impacting the fishes ability to survive," says de Souza. "Another effect from gold mining is the use of mercury to extract the gold in the river. This impacts all wildlife and principally local people that consume these fishes and other species in the watershed."And problems affecting the catfish don't stop with the tentacle-faced Romeos. "The whole ecosystem is interconnected -- you can't separate the species in it. Giant river otters love to eat these catfish, and jaguars have been observed to have higher mercury levels from eating contaminated fish or other species that feed on fish. This can have dire impacts on the whole ecosystem," says de Souza. "All the layers of the Amazon basin are interconnected from the rivers to the forest canopy."According to de Souza, the process of saving the Amazon starts with things like discovering new species and putting names on them. "Everything begins with naming a species and determining how many species you have. Once you have done the taxonomy then you can study the ecology, behavior, and do conservation action," says de Souza. "For example, The importance of these catfish to the bigger picture of Amazonian conservation inspired de Souza to name one of the new species after Connie Keller, the former chair of the Field Museum's Board of Trustees. "When I met Connie, I was immediately inspired by her contributions to our Science Action Center," says de Souza. "It might just be that the fish I named after her could help us protect this river system. Even as a fish, she'd be supporting conservation."With untold unknown species remaining in the Amazon, the work is far from over. "I have this undying curiosity -- what's around that bend, that corner, what's in that creek, what can I find? And this project was all about discovery, whether we were finding new species in rivers in Guyana or in jars in museum collections. This study included more than 500 specimens, but this is just a drop in the bucket -- there's still so much more to learn about
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New Species
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February 6, 2019
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https://www.sciencedaily.com/releases/2019/02/190206144454.htm
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Fossils of new oviraptorosaur species discovered in Mongolia
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A new oviraptorosaur species from the Late Cretaceous was discovered in Mongolia, according to a study published in February 6, 2019 in the open-access journal
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Oviraptorosaurs were a diverse group of feathered, bird-like dinosaurs from the Cretaceous of Asia and North America. Despite the abundance of nearly complete oviraptorosaur skeletons discovered in southern China and Mongolia, the diet and feeding strategies of these toothless dinosaurs are still unclear. In this study, Lee and colleagues described an incomplete skeleton of an oviraptorosaur found in the Nemegt Formation of the Gobi desert of Mongolia.The new species, named The finding of a new oviraptorosaur species in the Nemegt Formation, which consists mostly of river and lake deposits, confirms that these dinosaurs were extremely well adapted to wet environments. The authors propose that different dietary strategies may explain the wide taxonomic diversity and evolutionary success of this group in the region.The authors add: "A new oviraptorid dinosaur
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New Species
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February 6, 2019
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https://www.sciencedaily.com/releases/2019/02/190206115623.htm
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When does noise become a meaningful message?
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Background noise is generally regarded as a nuisance that can mask important sounds. But noise can be beneficial too. It can convey information about important environmental conditions and allow animals to make informed decisions. When bat researchers recorded and played back rain sounds for two different species of bats, both species chose to delay emergence from their roosts.
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"Bats are acoustic specialists," said Inga Geipel, a Tupper Postdoctoral Fellow at the Smithsonian Tropical Research Institute in Panama. "They are active at night and depend on sound to navigate their environment and to find food. When they hear the sound of rain at sunset, they decide to stay inside their roosts for a while longer."Bats have good reasons not to want to go out in the rain, as wet bats spend more energy when flying. Further, rain might also have a strong impact on the bats ability to navigate and find food through sound. Rain noise could mask prey sounds or jam the echolocation system of the hunting bats.Geipel and colleagues investigated the effect of rain noise on bat decision making. They studied two different species of bats: the common big-eared bat (Micronycteris microtis), which catches insects from leaves and other surfaces in forest understory, and the Pallas's mastiff bat (Molossus molossus) that hunts insects on the wing as they fly through open spaces."We wondered whether bats are staying longer in the safety of their roosts during rain storms and whether noise would inform them about the rainfall outside," Geipel said.To test their ideas, Geipel and her team put a speaker near entrances of bat roosts and broadcast recordings of heavy downpours. Simultaneously, they video-recorded the responses of the bats. For comparison, they also played recordings of normal forest sounds. Both species delayed their emergence from their roosts when they heard the sound of rain.The scientists also observed that the big-eared bats rapidly flew in and out of their roosts on short 'exploration flights,' likely meant to gather direct information about environmental conditions."Noise is often thought to be a nuisance with negative consequences," Geipel said. "But through this study we show that noise can actually be used as a salient informational cue. It can provide individuals with important information about their environment and when it's safe to hunt."
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New Species
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February 5, 2019
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https://www.sciencedaily.com/releases/2019/02/190205115401.htm
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Ice Age survivors or stranded travellers? A new subterranean species discovered in Canada
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The discovery of a new to science species of rare and primitive arthropod from the depths of a cave that was covered by a thick ice sheet until recently is certain to raise questions. In their study, published in the open-access journal
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According to the study, the dipluran's presence could either mean that terrestrial arthropods have indeed been able to survive within the deep subterranean habitats during the Last Glacial Maximum period some 26,500 years ago or it is the result of related species having dispersed to the area during the deglaciation, making their way from as far as Asia.Contrary to most people's expectations, the new creature was discovered only an easy hike away from the nearest town of Port Alberni (Vancouver Island, British Columbia). There, cavers Craig Wagnell, Tawney Lem and Felix Ossigi-Bonanno from the Central Island Caving Club, together with Alberto Sendra, Alcala University (Spain), reported a remarkable, previously unknown species of dipluran from a couple of caves recently unearthed in the small limestone karstic area.Named Haplocampa wagnelli, the new species pays tribute to co-author Craig Wagnell, "who has dedicated many years sampling and exploring in Vancouver Island caves."Unlike most cave-adapted campodeid diplurans, whose bodies and appendages are characteristically elongated and slender -- a "trademark" feature for strictly underground arthropods -- the new species (Haplocampa wagnelli) has only slightly elongated antennae and legs and a thicker body. This is the reason why the researchers conclude that the species is not exclusively subterranean and is likely to also be present in soil habitats. On the other hand, its North American sister species seem to be even less adapted to life underground.Interestingly, the scientists note close relationships between the genus (Haplocampa) of the new species and three others known from the two sides of the north Pacific Ocean: Pacificampa (Japanese Islands and the Korean Peninsula), Metriocampa (Siberia) and Eumesocampa (North America). According to the team, this is evidence for dispersal events where populations would cross over the old Bering Land Bridge, which used to connect America and Asia.Furthermore, the new species is also one of the most northerly cave-adapted dipluran species, found at a latitude of 49º north. Some 26,500 years ago, its modern habitat would have been located underneath the Cordilleran Ice Sheet, part of the Late Wisconsinan North American ice sheet complex.
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New Species
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February 5, 2019
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https://www.sciencedaily.com/releases/2019/02/190205102625.htm
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Deaf moth evolves sound-production as a warning to outwit its predator
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A genus of deaf moth has evolved to develop an extraordinary sound-producing structure in its wings to evade its primary predator the bat. The finding, made by researchers from the University of Bristol and Natural History Museum, is described in
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It's already known that some species of moth have evolved a range of defensive mechanisms to evade insectivorous bats' highly-tuned echolocation (biosonar) detection skills. The discovery of a wingbeat-powered sound producing structure in the wings of a deaf moth is completely new.Many larger species of moth use ears tuned to detect the echolocation calls of bats to provide an early warning of approaching bats allowing them to perform evasive manoeuvres. While others, such as some silk moths, have hindwing tails that produce salient echoes which act as false targets to bats -- like the towed decoys fighter planes use against radar guided missiles.The team of researchers from Bristol's School of Biological Sciences and the Natural History Museum, London, were studying a group of smaller British moths known as the small ermine moths (The sounds these moths produce are very similar to sounds produced by larger moths, such as the tiger moths, which warn bats of the moth's distastefulness or toxicity (known as acoustic aposematism). At night an unpalatable moth cannot provide a bat with a conspicuous warning colour, so instead it warns its predator acoustically. The team suggest that small ermine moths are acoustically mimicking unpalatable, sound producing moths, to warn bats of their own distastefulness.Typically, anti-bat sounds are produced by structures called tymbals, small areas of thin cuticle on a moth's body, which are connected to a muscle. As the muscle contracts, the tymbal buckles and produces a click, then as the muscle relaxes, the tymbal snaps back to its resting state and produces another click. However, the wing-based tymbals of small ermine moths are not connected to a muscle, instead sound production is initiated by the moth's wingbeat during flight.Liam O'Reilly, the study's lead author and a PhD student at Bristol's School of Biological Sciences, said: "Bat defences in larger moths are well studied, however, the defences in smaller moths are not."Many animals use a conspicuous visual signal such as bright colouration to warn their predators of a defence, but at night an unpalatable moth cannot provide a bat with a visual warning signal, so instead it warns its predator acoustically through a clear sound -- loud high frequency (ultrasonic) clicks."The fact that sound production in these moths has remained undiscovered for so long reminds us of how little we know of the complex acoustic world of bats and moths."Following this discovery, the team are working with material scientists to find out the exact mechanism by which the small ermine moth tymbal produces sound. Specialists in buckling mechanics are working on modelling the system to artificially recreate the sounds of these moths.
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New Species
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February 4, 2019
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https://www.sciencedaily.com/releases/2019/02/190204114602.htm
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More than 100 new gut bacteria discovered in human microbiome
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Scientists working on the gut microbiome have discovered and isolated more than 100 completely new species of bacteria from healthy people's intestines. The study from the Wellcome Sanger Institute, Hudson Institute of Medical Research, Australia, and EMBL's European Bioinformatics Institute, has created the most comprehensive collection of human intestinal bacteria to date. This will help researchers worldwide to investigate how our microbiome keeps us healthy, and its role in disease.
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Reported today (4th February) in About 2 per cent of a person's body weight is due to bacteria and the intestinal microbiome is a major bacterial site and an essential contributor to human health. Imbalances in our gut microbiome can contribute to diseases and complex conditions such as Inflammatory Bowel Disease, Irritable Bowel Syndrome allergies and obesity. However, as many species of gut bacteria are extremely difficult to grow in the laboratory, there is a huge gap in our knowledge of them.In this study, researchers studied faecal samples from 20 people from the UK and Canada, and successfully grew and DNA sequenced 737 individual bacterial strains from these. Analysis of these isolates revealed 273 separate bacterial species, including 173 that had never previously been sequenced. Of these, 105 species had never even been isolated before.Dr Samuel Forster, first author on the paper from the Wellcome Sanger Institute and Hudson Institute of Medical Research, Australia, said: "This study has led to the creation of the largest and most comprehensive public database of human health-associated intestinal bacteria. The gut microbiome plays a major in health and disease. This important resource will fundamentally change the way researchers study the microbiome."Standard methods to understand how the gut microbiome impacts on human health involves sequencing the DNA from mixed samples of gut bacteria to try to understand each component. However, these studies have been severely hampered by the lack of individually isolated bacteria and reference genomes from them.The new culture collection and reference genomes will make it much cheaper and easier for researchers to determine which bacteria are present within communities of people and research their role in disease.Dr Rob Finn, an author from EMBL's European Bioinformatics Institute, said: "For researchers trying to find out which species of bacteria are present in a person's microbiome, the database of reference genomes from pure isolates of gut bacteria is crucial. Then if they want to test a hypothesis, for example that a particular species is enriched in a certain disease, they can get the isolate itself from the collection and physically test in the laboratory if this species seems to be important."Dr Trevor Lawley, Senior author from the Wellcome Sanger Institute, said: "This culture collection of individual bacteria will be a game-changer for basic and translational microbiome research. By culturing the unculturable, we have created a resource that will make microbiome analysis faster, cheaper and more accurate and will allow further study of their biology and functions. Ultimately, this will lead us towards developing new diagnostics and treatments for diseases such as gastrointestinal disorders, infections and immune conditions."
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New Species
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February 1, 2019
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https://www.sciencedaily.com/releases/2019/02/190201114117.htm
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Butterflies thrive in grasslands surrounded by forest
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For pollinating butterflies, it is more important to be close to forests than to agricultural fields, according to a study of 32,000 butterflies by researchers at Linköping University and the Swedish University of Agricultural Sciences (SLU) in Uppsala. The results provide important knowledge about how to plan and manage the landscape to ensure the survival of butterflies.
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Semi-natural grasslands are one of Sweden's most species-rich habitats, with a multitude of plants and butterflies. However, the amount of such areas has been reduced by 90% in the past 100 years. Semi-natural grasslands are often preserved as just small fragments in the landscape. Their loss has led to many species of butterfly being decimated, and in some cases eliminated from parts of Sweden. The researchers who carried out the new study, published in the scientific journal "Several of our results are really exciting, and demonstrate that the species richness of semi-natural grasslands is influenced by other factors than the properties of the grasslands themselves. The surrounding landscape is also important for butterflies. If the semi-natural grasslands are embedded within large regions of arable land, the number of species is reduced," says Karl-Olof Bergman, senior lecturer in the Department of Physics, Chemistry and Biology, IFM.The species richness of butterflies was in general greater in locations where large areas of semi-natural grasslands lay within 10-20 kilometres around the studied semi-natural grassland. Another important landscape feature linked to a larger number of butterfly species was if the grasslands were surrounded by forest."Forests have habitats that butterfly can use, such as forest edges, power lines, forestry tracks, glades and cleared areas. Together with semi-natural grasslands, forests can be used to create landscapes that butterflies thrive in. Agricultural fields, in contrast, seem to have few resources that the butterflies can use, and the resources that are available benefit only a few species," says Karl-Olof Bergman.Different species of butterfly reacted differently to the surrounding landscape. Some species were sensitive to the immediate vicinity, while others were influenced by the composition of the surrounding landscape further away from the semi-natural grasslands."These results are important if we are to preserve the butterflies and other pollinators in the countryside, and create and preserve landscape that enables them to survive. The most species-rich regions for butterflies in southern Sweden are those that still have relatively large areas of semi-natural grasslands, principally in eastern Sweden including parts of Östergötland. It is important that these habitats are preserved," says Karl-Olof Bergman.The study used data about butterflies from NILS, the National Inventory of Landscapes in Sweden. The research has been financed by, among other bodies, WWF Sweden, the Formas research council, the Swedish Environmental Protection Agency, and the Swedish Board of Agriculture.
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New Species
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January 31, 2019
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https://www.sciencedaily.com/releases/2019/01/190131125947.htm
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Climate change and infertility -- a ticking time bomb?
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Rising temperatures could make some species sterile and see them succumb to the effects of climate change earlier than currently thought, scientists at the University of Liverpool warn.
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"There is a risk that we are underestimating the impact of climate change on species survival because we have focused on the temperatures that are lethal to organisms, rather than the temperatures at which organisms can no longer breed," explains evolutionary biologist Dr Tom Price from the University's Institute of Integrative Biology.Currently, biologists and conservationists are trying to predict where species will be lost due to climate change, so they can build suitable reserves in the locations they will eventually need to move to. However, most of the data on when temperature will prevent species surviving in an area is based on the 'critical thermal limit' or CTL -- the temperature at which they collapse, stop moving or die.In a new opinion article published in Certain groups are thought to be most vulnerable to climate-induced fertility loss, including cold-blooded animals and aquatic species. "Currently the information we have suggests this will be a serious issue for many organisms. But which ones are most at risk? Are fertility losses going to be enough to wipe out populations, or can just a few fertile individuals keep populations going? At the moment, we just don't know. We need more data," says Dr Price.To help address this, the researchers propose another measure of how organisms function at extreme temperatures that focuses on fertility, which they have called the Thermal Fertility Limit or 'TFL'."We think that if biologists study TFLs as well as CTLs then we will be able to work out whether fertility losses due to climate change are something to worry about, which organisms are particularly vulnerable to these thermal fertility losses, and how to design conservation programmes that will allow species to survive our changing climate."We need researchers across the world, working in very different systems, from fish, to coral, to flowers, to mammals and flies, to find a way to measure how temperature impacts fertility in that organism and compare it to estimates of the temperature at which they die or stop functioning," urges Dr Price.The work was carried out in collaboration with scientists from the University of Leeds, University of Melbourne and Stockholm University and was funded by the UK Natural Environment Research Council (NERC).
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New Species
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January 29, 2019
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https://www.sciencedaily.com/releases/2019/01/190129124803.htm
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Huge step forward in decoding genomes of small species
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For the first time, scientists have read the whole genetic code of one single tiny mosquito. Traditionally, it has been difficult to extract enough DNA from insects and other small organisms to build a high quality genome for a single individual. Scientists from the Wellcome Sanger Institute and Pacific Biosciences worked in partnership to advance technology and lower the starting amount of DNA needed to just 'half a mosquito-worth', producing the first high quality whole genome of a single mosquito.
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The results, reported in In 2018, collaborating organisations around the world officially launched the Earth BioGenome Project*, a global mission to sequence all 1.5 million known species of animals, plants, protozoa and fungi on Earth. The Earth BioGenome Project will ultimately create a new foundation for biology to drive solutions for preserving biodiversity and sustaining human societies.When studying the biology of a species, the genome of a single individual can be used as a reference to explore the genetic differences attributing to varying susceptibility to disease, fitness and adaptation within others of the same species.However, it is much easier to extract DNA and sequence the genome of some species over others. In particular, it has not been possible to assemble the genome from single small organisms such as insects using current sequencing technology. This leaves the genetic codes of individual insects and other similar-sized species inaccessible.Until now, scientists have had to pool the DNA of multiple individuals of the same species, or inbreed them to produce genetically related individuals, in order to gather enough DNA to build a genome. This creates challenges when putting the genetic sequence back together again after it has been sequenced, as it can be difficult to know which genetic fragment came from which individual, resulting in genome sequences full of gaps and errors.In the new study, Sanger Institute researchers worked with scientists at the sequencing technology provider, Pacific Biosciences (PacBio) to produce the first high-quality genome from a single insect using new technology that reduces the starting DNA needed.Dr Mara Lawniczak, co-lead author from the Wellcome Sanger Institute, said: "This advancement in sequencing technology is vital to decoding the genomes of a huge number of species in the tree of life, giving us greater power to completely understand genetic diversity within even the tiniest species."Sanger scientists extracted DNA from a single Anopheles coluzzii mosquito and sent it to PacBio in the United States.To reduce the amount of starting DNA required for genome sequencing, the PacBio team tweaked the preparation chemistry for genomic sequencing. They removed two steps from the process that result in the loss of DNA: shearing -- cutting the DNA fragments into certain size ranges, and size selection -- removing the unwanted small fragments.The team were able to generate a high quality genome from just 100 nanograms of DNA -- about half a mosquito's worth -- which is over an order of magnitude less than the 5 micrograms of DNA previously required.The resulting genome was quick to assemble, complete and accurate. As a result of the complete genomic picture, nearly half of the previously unplaced DNA fragments for this mosquito species could now be placed within the correct chromosomal context.Dr Jonas Korlach, Chief Scientific Officer at Pacific Biosciences and co-lead author of the study, said: "This has been a real team effort and we've thoroughly enjoyed the collaboration in developing this protocol. It's a great example of the significant advances we can bring to the scientific community when academia and industry work together."This advance could have positive potential for humans as well, for example in the future it could be possible to assemble the whole genetic code of a patient's cancer, from a single biopsy.Dr Peter Campbell from the Wellcome Sanger Institute, who was not involved in the study, said: "The sequencing technology also shows promise for reading the whole genetic code of an individual patient's cancer biopsy. 100 nanograms of DNA collected with a needle prick could be enough to give a detailed view of the cancer's genetics and inform targeted therapies for that specific patient."
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New Species
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January 28, 2019
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https://www.sciencedaily.com/releases/2019/01/190128105224.htm
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New family of fungi threatens a UNESCO-listed 8-century-old cathedral in Portugal
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To be listed as UNESCO World Heritage requires special care and protection of valuable cultural monuments and pieces of Art from threats such as biodeterioration caused by microcolonial black fungi. The culprits lodge their branch-like structures (hyphae) deep into the stone forming fissures and cracks and also produce polysaccharides that trigger corrosion.
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These fungi are well known for their unique resistance to hostile environmental conditions, including extreme temperatures, high solar and UV radiation, severe droughts and low abundance of nutrients. As a result, they survive in hot and cold deserts, saltpans, acidic and hydrocarbon-contaminated sites and exposed rocks surfaces. All of this makes them a particular challenge to conservationists and biologists who care for historic monuments.During a multi-disciplinary scientific survey at the 8-century-old cathedral Sé Velha de Coimbra (Old Cathedral of Coimbra), which is the only Romanesque cathedral in Portugal to have survived relatively intact since the Reconquista times, scientists retrieved a peculiar slow-growing microcolonial black fungus.What João Trovão of the University of Coimbra (Portugal) and his colleagues were looking at turned out to be a species of a whole new family (Aeminiaceae) in the order of the sooty mould fungi. The new species, its new genus and the novel family are described in the open-access journal To define the new group of fungi, the researchers first scraped off samples from a deteriorated limestone artwork in the "Santa Maria" chapel and then conducted an extensive and integrative analysis, based on morphological, physiological, ecological characters and DNA sequences.As for the origin of the previously unknown fungus, the scientists hypothesise that the species had 'arrived' at the Old Cathedral of Coimbra with the limestone used during its construction. Coming from the unique nearby areas of Ançã and Portunhos, such limestone has been used on several of the "Our Ladies of the O" statues, as well as in the portal of the Royal Hospital in Santiago de Compostela (Spain). Currently, these fungi are considered endemic to the limestone quarries in the Iberian Peninsula."Regarding stone monuments exposed to the environment, microcolonial black fungi are considered one of the main culprits for the phenomenon of stone biodeterioration, being responsible for severe aesthetic, biochemical and biophysical alterations," comment the scientists."It is, therefore, crucial to gather deeper knowledge regarding their biodiversity and their biological, ecological and physiological unique characteristics, in order to span our knowledge regarding these fungi and, at the same time, allow the development and improvement of tools to protect stone monuments from their deteriorative effects."
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New Species
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January 25, 2019
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https://www.sciencedaily.com/releases/2019/01/190125172944.htm
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Record-breaking salamander
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Researchers at UT have discovered the largest individual of any cave salamander in North America, a 9.3-inch specimen of Berry Cave salamander. The finding was published in
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"The record represents the largest individual within the genus The find is making scientists reexamine growth limits of these animals in harsh environments and how hospitable underground environments really are.Salamanders can be found in a variety of habitats across Tennessee. Some species have adapted to live in cave environments, which are thought of as extreme and inhospitable ecosystems due to the absence of light and limited resources.Salamanders are one of only two vertebrate animal groups to have successfully colonized caves. The other is fish, said Gladstone.The record-breaking specimen had some damage to the tail, leading researchers to believe that it was once nearly 10 inches long.The Berry Cave Salamander can be found in only 10 sites in eastern Tennessee, and in 2003 it was placed on the US Fish and Wildlife Service's Candidate Species List for federal protection."This research will hopefully motivate additional conservation efforts for this rare and vulnerable species," said Gladstone.
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New Species
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January 24, 2019
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https://www.sciencedaily.com/releases/2019/01/190124095100.htm
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It's a bird-eat-bird world
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Baby birds and eggs are on the menu for at least 94 species of animals in Australia's forests and woodlands, according to new research from The University of Queensland.
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PhD candidate Graham Fulton reviewed 177 existing bird studies across the country, identifying Australia's most prolific nest predators and the factors affecting nest attacks."Predators attacking bird nests -- known as nest predation -- is the leading cause of nesting failure," Mr Fulton said."Predators are always looking for their next meal and now we know who Australia's common culprits are."In the reviewed research, 94 nest predators -- from birds to reptiles to ants -- were found to be attacking both natural and artificial nests."If you take out the artificial nests, it's 69 species, and from that data there's a clear dominant nest attacker in the Australia's natural environment -- the pied currawong."The pied currawong was found to be taking eggs and young from 29 different bird species; followed by the square-tailed kite (18 species), the tiger snake (15 species), the laughing kookaburra (10 species) and the grey strike-thrush (eight species)."These five nest predators were recorded as attacking a whopping 40 per cent of the prey measured by the number of prey species taken," Mr Fulton said."The other 60 per cent of predation was carried out by the other 64 species, which included, by order of importance: birds, mammals, reptiles, frogs and ants."It also appears that the young and eggs of small 'cup' nesting birds, like the willie wagtail, are more often on the menu than other birds."This is probably because birds like willie wagtails are easily seen in the open, and they're probably delicious and certainly nutritious," Mr Fulton said."And predation at 'cup' and 'dome' nests was more frequently reported than at burrow, ground and hollow nests."When birds attack, they also prefer to eat the babies of other bird species whose parents are a quarter to a third of the predators' weight."It's a bird-eat-bird world out there, but at least we now know who's doing the eating."
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New Species
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January 23, 2019
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https://www.sciencedaily.com/releases/2019/01/190123105757.htm
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Copy cats: When is a bobcat not a bobcat?
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Two UBC Okanagan biologists, who have publicly solicited images of wild cats for their research, have answered that question.
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Their recently published study explains how hard it can be when it comes to wildlife classification -- even experts have difficulty agreeing on whether a cat in a picture is a bobcat or a lynx.Biology Professor Karen Hodges and master's student TJ Gooliaff collected and compared wildlife images for several years as part of their research tracking bobcat and lynx distributions in British Columbia. Camera trapping and solicitation of wildlife pictures through citizen science have become common tools in ecological research, explains Gooliaff.While it's generally easy to collect many images of animals, some species are difficult to tell apart, making species classification challenging."Camera-trapping and citizen-science studies collect many wildlife images for which correct species classification is crucial," says Gooliaff. "Even low misclassification rates can result in erroneous estimation of the geographic range or habitat use of a species -- including underestimation of the occupancy, habitat preferences or distribution of a species. This potentially hinders conservation and management efforts."There are some species, such as mountain goats and porcupines, where it's obvious. But for others, including bears, deer, lemurs, wild cats and antelopes, classification to a species may be unreliable as the animals can be similar in size, shape or colour. It gets even trickier when the pictures are blurry, taken in poor lighting, show only part of the animal or when only one image is available for a given animal.In a 2018 study published in the Because lynx and bobcats are similar, Gooliaff and Hodges then measured agreement among experts who were asked to distinguish between bobcats and lynx from those images. The researchers asked 27 individual bobcat and lynx authorities to classify the species in a subsample of 300 images to see how often the experts agreed on whether it was a bobcat or a lynx.What became clear was that the experts found it difficult to tell bobcats and lynx apart -- indeed, many images were labelled as "unknown" by the experts -- and they did not always agree with each other. Experts were inconsistent even with themselves, changing their classifications of some images when they were asked to reclassify the same pictures months later.Gooliaff and Hodges also examined if agreement among experts varied with what part of the animal was in each image (paws, head, tail, etc.), the habitat in the background, and whether it was day or night. These factors all affected how many experts agreed on the species in each image."These results are particularly troubling given that the images were all of high photographic quality," says Gooliaff.Hodges says this study helps researchers improve how they work with images, by knowing when misidentifications are most likely. Further, classification of images of similar?looking species should not be relied upon for critical conservation or management decisions. Instead, physical or genetic evidence should be required in these cases.She also emphasises that pictures provided by the public are becoming a powerful tool in wildlife research and eventual conservation and management efforts. This research benefits citizen science and image-based studies, as they continue to refine how people use submitted images."We encourage researchers who use images to be more willing to call the species in a picture "unknown" or to use them as a screen for habitats or regions where more survey work should be done, rather than trusting images alone."The image study, partially funded by a Natural Sciences and Engineering Research Council grant, was recently published in
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January 21, 2019
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https://www.sciencedaily.com/releases/2019/01/190121103414.htm
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Ancient carpet shark discovered with 'spaceship-shaped' teeth
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The world of the dinosaurs just got a bit more bizarre with a newly discovered species of freshwater shark whose tiny teeth resemble the alien ships from the popular 1980s video game Galaga.
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Unlike its gargantuan cousin the megalodon, Galagadon nordquistae was a small shark (approximately 12 to 18 inches long), related to modern-day carpet sharks such as the "whiskered" wobbegong. Galagadon once swam in the Cretaceous rivers of what is now South Dakota, and its remains were uncovered beside "Sue," the world's most famous T. rex fossil."The more we discover about the Cretaceous period just before the non-bird dinosaurs went extinct, the more fantastic that world becomes," says Terry Gates, lecturer at North Carolina State University and research affiliate with the North Carolina Museum of Natural Sciences. Gates is lead author of a paper describing the new species along with colleagues Eric Gorscak and Peter J. Makovicky of the Field Museum of Natural History."It may seem odd today, but about 67 million years ago, what is now South Dakota was covered in forests, swamps and winding rivers," Gates says. "Galagadon was not swooping in to prey on T. rex, Triceratops, or any other dinosaurs that happened into its streams. This shark had teeth that were good for catching small fish or crushing snails and crawdads."The tiny teeth -- each one measuring less than a millimeter across -- were discovered in the sediment left behind when paleontologists at the Field Museum uncovered the bones of "Sue," currently the most complete T. rex specimen ever described. Gates sifted through the almost two tons of dirt with the help of volunteer Karen Nordquist, whom the species name, nordquistae, honors. Together, the pair recovered over two dozen teeth belonging to the new shark species."It amazes me that we can find microscopic shark teeth sitting right beside the bones of the largest predators of all time," Gates says. "These teeth are the size of a sand grain. Without a microscope you'd just throw them away."Despite its diminutive size, Gates sees the discovery of Galagadon as an important addition to the fossil record. "Every species in an ecosystem plays a supporting role, keeping the whole network together," he says. "There is no way for us to understand what changed in the ecosystem during the mass extinction at the end of the Cretaceous without knowing all the wonderful species that existed before."Gates credits the idea for Galagadon's name to middle school teacher Nate Bourne, who worked alongside Gates in paleontologist Lindsay Zanno's lab at the N.C. Museum of Natural Sciences.
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New Species
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January 19, 2019
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https://www.sciencedaily.com/releases/2019/01/190119095710.htm
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New species of snake found in stomach of predator snake
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Herpetologists at The University of Texas at Arlington have described a previously unknown species of snake that was discovered inside the stomach of another snake more than four decades ago.
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The new snake has been named The researchers' work identifies The specimen was found in the stomach of a Central American coral snake -- a species that has been known to eat smaller snakes -- by palm harvesters in the southern Mexico state of Chiapas in 1976. The 10-inch long specimen was preserved in a museum collection. Amazingly, a live specimen has never been found in the ensuing 42 years."This small snake was obtained now over 40 years ago, and the report of its discovery has been a long time in coming," the co-authors wrote in the The first two of those features are not found in any other known snake in the family Colubridae in the Western Hemisphere. Colubridae is the largest snake family and includes just over 51 percent of all known living snake species.Utilizing the vast resources of UTA's Amphibian and Reptile Diversity Research Center for comparative purposes, the researchers made CT scans of dozens of specimens of snakes. The biologists believe that due to some of the specimen's physical features, "This provides evidence of just how secretive some snakes can be," Campbell told National Geographic, which ran a story about the discovery in its Dec, 19, 2018, edition. "Combine their elusive habits with restricted ranges and some snakes do not turn up often."He noted said that because of the snake's unique nature, the Chiapas highlands area of southern Mexico where it was found all those years ago should be considered for protected status, so that more unknown species can be discovered and not face possible extinction.
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New Species
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January 17, 2019
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https://www.sciencedaily.com/releases/2019/01/190117160404.htm
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Orchards in natural habitats draw bee diversity, improve apple production
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Apple orchards surrounded by agricultural lands are visited by a less diverse collection of bee species than orchards surrounded by natural habitats, according to a new Cornell University-led study, published in the journal
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In turn, apple production suffers when fewer, more closely-related species of bees pollinate an orchard. Production improves in orchards surrounded by natural habitats, which then draw a broader selection of species to apple blossoms.The researchers examined 10 years of data from 27 New York state apple orchards. The study accounted for the types of landscapes that surround these orchards, measured apple production and surveyed the species of bees that visited each orchard.The researchers also reconstructed the evolutionary history and relatedness of New York native bee species to better understand species patterns that played out across these orchard bee communities. This reconstruction is represented by a branching tree-like diagram of related species, called a phylogeny."Orchards that have bee communities that are more closely related to each other did worse in terms of their fruit production, and the communities that are more broad across the phylogeny did much better," said Heather Grab, Ph.D., the paper's first author and a postdoctoral researcher in the lab of Katja Poveda, associate professor of entomology and a co-author of the study. Brian Danforth, professor of entomology, is a senior author of the study.Species of bees exhibit different behaviors in how and when they pollinate flowers. Some species approach from the side, others from the top, and they each may feed at different times of day and with varied frequencies, all of which affect how completely an apple flower is pollinated.Organs in apple flowers must receive a certain number of pollen grains in order to develop a full complement of seeds. When seeds do well, the tissue that supports those seeds, the fleshy part of the fruit, is also more fully developed."If only half of the seeds mature fully, then the fruit is misshapen," which in turn affects weight and salability, Grab said.In this way, habitats that surround farms affect the diversity of bee communities and, thus, an orchard's productivity.Co-author Michael Branstetter, a research entomologist at the United States Department of Agriculture-Agricultural Research Service in Logan, Utah, created the phylogeny. Other co-authors are Greg Loeb, Cornell professor of entomology; Mia Park, Ph.D., a postdoctoral fellow at North Dakota State University; and Eleanor Blitzer, a biologist at Carroll College.The study was funded by the USDA and the Atkinson Center for a Sustainable Future.
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New Species
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January 15, 2019
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https://www.sciencedaily.com/releases/2019/01/190115121103.htm
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Scientists identify two new species of fungi in retreating Arctic glacier
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Two new species of fungi have made an appearance in a rapidly melting glacier on Ellesmere Island in the Canadian Arctic, just west of Greenland. A collaborative team of researchers from Japan's National Institute of Polar Research, The Graduate University for Advanced Studies in Tokyo, Japan, and Laval University in Québec, Canada made the discovery.
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The scientists published their results on DATE in two separate papers, one for each new species, in the "The knowledge of fungi inhabiting the Arctic is still fragmentary. We set out to survey the fungal diversity in the Canadian High Arctic," said Masaharu Tsuji, a project researcher at the National Institute of Polar Research in Japan and first author on both papers. "We found two new fungal species in the same investigation on Ellesmere Island."One species is the 10th to join the genus The samples of fungi were collected from the unofficially named Walker Glacier. The designation comes from Paul T. Walker, who installed the datum pole that measures the glacier's growth and shrinkage, in 1959. At the time of sample collection in 2016, measurements showed that the glacier was receding at a rate two-and-a-half times faster than its retreat over the previous 50 years."Climate-related effects have been observed in this region over the last 20 years," Tsuji said. "Soon, some of the glaciers may completely melt and disappear."Only about five percent of fungi species have been discovered, but their function across ecological climates is well understood -- from the tropics to the Arctic, fungi decompose dead organic material. Each species operates a little differently, but their general role is to reintroduce nutrients from dead plant material back into the ecosystem. If the glaciers melt, the fungi lose their habitat. The results could have catastrophic knock-on effects throughout the ecosystem, according to Tsuji, although more research is needed to understand exactly how the changing climate is influencing fungi beyond destroying their habitat.Next, Tsuji and his team plan to survey the fungi in Ward Hunt Lake, the northern most lake in the world. It is on Ward Hunt Island, just off the northern coast of Ellesmere Island, and less than 500 miles from the North Pole"Normally, the lake's ice doesn't melt during the summer season. However, the ice melted completely in 2016. We plan to continuously check how the lake's fungal diversity changes," Tsuji said. The different species could evolve, or, potentially, go extinct. "Eventually, we plan to compile all of our studies to provide an overview of terrestrial ecosystems in the Arctic and Antarctic regions."
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New Species
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January 14, 2019
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https://www.sciencedaily.com/releases/2019/01/190114161131.htm
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Marine bacterium sheds light on control of toxic metals
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An ocean-dwelling bacterium has provided fresh insights into how cells protect themselves from the toxic effects of metal ions such as iron and copper, in research led by the University of East Anglia (UEA).
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Although essential to life, metal ions can also generate reactive oxygen species (ROS) -- highly reactive molecules that damage cells as they try to form bonds with other molecules.In humans, reactive oxygen species are linked to ageing and also to diseases such as cancers.To reduce the toxic effects of iron, a family of proteins called ferritins detoxify and store the metal ions within their football-shaped protein shell, generating a safe but accessible deposit that can be drawn on by the cell when iron in the environment becomes scarce.Working with researchers at the University of Essex and the Scripps Institute in California, the UEA team have discovered how a ferritin in one particular marine bacterium succeeds in carrying out this detoxification process.Unusually, the bacterium produces the ferritin in response to high levels of copper, not iron.The team discovered that there was no direct interaction between the ferritin and the copper, but instead the ferritin catalysed a new kind of reaction between oxygen and iron. This generated a form of the ferritin that has an enhanced ability to detoxify ROS directly, whilst also carrying out its iron storage and detoxification roles.Prof Nick Le Brun, from UEA's School of Chemistry, said: "We believe the iron involved in this new pathway has been displaced from other iron-containing proteins by the copper, and the bacterium manages the toxicity of the displaced iron by producing the ferritin. This of particular interest because the ferritin involved more closely resembles those in animals than in other bacteria."This type of process has not previously been spotted by scientists and confirms that there are many different ferritin mechanisms at work across different organisms.Dr Dima Svistunenko, from the University of Essex, said: "The chemistry between iron and O2, that generates harmful ROS, has been studied in many systems, and that includes a number of ferritins from a range of organisms. But, here, we saw reactivity that is entirely new, pointing to an unprecedented detoxification process that involves long-range electron transfer across the protein molecule."A search of genomic databases carried out by the team also revealed that many other similar marine bacteria may produce similar ferritins under conditions of stress.The team now plan to expand their research to investigate how widespread the new mechanism is."None of the previously studied ferritins, or indeed iron enzymes in general, react in the way this newly discovered ferritin does," said Prof Le Brun."This novel chemistry not only represents a breakthrough for our understanding of natural anti-oxidant processes, it also reveals new possibilities for future engineered biocatalysts that could, for example, find use in drug development."
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New Species
| 2,019 |
January 11, 2019
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https://www.sciencedaily.com/releases/2019/01/190111095106.htm
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Skull scans tell tale of how world's first dogs caught their prey
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Analysis of the skulls of lions, wolves and hyenas has helped scientists uncover how prehistoric dogs hunted 40 million years ago.
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A study has revealed that the first species of dog -- called The findings also show that the largest dog species ever to live -- known as Epicyon haydeni -- hunted in a similar way. The animals -- which lived from 16 until seven million years ago -- could grow to the size of a grizzly bear.Comparisons between computerised scans of fossils and modern animals have shed light on the hunting methods used by prehistoric members of a group of mammals known as carnivorans. These include modern-day foxes, wolves, cougars and leopards.Scientists at the Universities of Edinburgh and Vienna used the scans to create digital models of the inner ears of 36 types of carnivoran, including six extinct species.The team found that the size of three bony canals in the inner ear -- the organ that controls balance and hearing -- changed over millions of years as animals adopted different hunting styles.Faster predators -- such as cheetahs, lions and wolves -- developed large ear canals that enable them to keep their head and vision stable while ambushing or chasing prey at speed, the team says.Their findings reveal that inner ear structure indicates whether a species descended from dog-like animals or belongs to one of four families of animals resembling cats. A distinctive angle between two parts of the inner ear is much larger in dog-like animals, the team found.The study is based on research carried out by Julia Schwab, a current PhD student at the University of Edinburgh, during her MSc studies at the University of Vienna, Austria. It is published in the journal Ms Schwab, based in the University of Edinburgh's School of GeoSciences, said: "For me, the inner ear is the most interesting organ in the body, as it offers amazing insights into ancient animals and how they lived. The first dog and the largest-ever dog are such fascinating specimens to study, as nothing like them exists in the world today."
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New Species
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January 8, 2019
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https://www.sciencedaily.com/releases/2019/01/190108084435.htm
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The first case of a Portuguese beetle living exclusively in groundwater
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A diving beetle demonstrating various adaptations to the life underground, including depigmentation and evolutionary loss of eyes, was discovered at the bottom of a clay pound in the cave Soprador do Carvalho, Portugal. The species turned out to be the very first in the whole order of beetles (Coleoptera) to be known exclusively from the underground waters of the country.
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Despite not being able to find any other specimens during their study -- save for the single female, the team of Dr Ignacio Ribera, Institute of Evolutionary Biology (Spain) and Prof Ana Sofia P. S. Reboleira, University of Copenhagen (Denmark) identified the beetle as new to science, thanks to its unambiguous morphology in combination with molecular data.Aptly named With a uniformly pale orange body measuring 2.8 mm in length and 1.1 mm in its widest part, the beetle is larger than the rest species known in its genus, and its appendages are longer and more slender. While blindness and depigmentation are clear adaptation to life away from sunlight, the elongated limbs and antennae reflect poor swimming abilities needed in a subterranean habitat. Going for 4 km in horizontal direction, Soprador do Carvalho is the largest in the Dueça cave system, located in the north-eastern part of the Sicó karst area in central Portugal. In recent years, the cave is being explored for tourism."The knowledge of the subterranean fauna from Portugal has significantly increased over the last decade, with the description of a high number of obligate subterranean species (tripling their number) and the establishment of new biogeographic patterns," explain the authors of the study. "A high number of these species are stygobiont (i.e. confined to groundwater), mostly from wells in the north of the country, where evapotranspiration is higher."
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New Species
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January 7, 2019
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https://www.sciencedaily.com/releases/2019/01/190107150740.htm
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Evolution used same genetic formula to turn animals monogamous
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Why are some animals committed to their mates and others are not? According to a new study led by researchers at The University of Texas at Austin that looked at 10 species of vertebrates, evolution used a kind of universal formula for turning non-monogamous species into monogamous species -- turning up the activity of some genes and turning down others in the brain.
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"Our study spans 450 million years of evolution, which is how long ago all these species shared a common ancestor," said Rebecca Young, research associate in UT Austin's Department of Integrative Biology and first author of the study published today in the journal The authors define monogamy in animals as forming a pair bond with one mate for at least one mating season, sharing at least some of the work of raising offspring and defending young together from predators and other hazards. Researchers still consider animals monogamous if they occasionally mate with another.The researchers studied five pairs of closely related species -- four mammals, two birds, two frogs and two fish -- each with one monogamous and one non-monogamous member. These five pairs represent five times in the evolution of vertebrates that monogamy independently arose, such as when the non-monogamous meadow voles and their close relatives the monogamous prairie voles diverged into two separate species.The researchers compared gene expression in male brains of all 10 species to determine what changes occurred in each of the evolutionary transitions linked to the closely related animals. Despite the complexity of monogamy as a behavior, they found that the same changes in gene expression occurred each time. The finding suggests a level of order in how complex social behaviors come about through the way that genes are expressed in the brain.This study covers a broader span of evolutionary time than had been explored previously. Other studies have looked at genetic differences related to evolutionary transitions to new traits, but they typically focus on animals separated by, at most, tens of millions of years of evolution, as opposed to the hundreds of millions of years examined with this study."Most people wouldn't expect that across 450 million years, transitions to such complex behaviors would happen the same way every time," Young said.The paper's other UT Austin authors are senior author professor Hans Hofmann and professor Steven Phelps. Researchers examined gene activity across the genomes of the 10 species, using RNA-sequencing technology and tissue samples from three individuals of each species. The scientists detected gene-activity patterns across species using bioinformatics software and the Texas Advanced Computing Center's Wrangler data-intensive supercomputer. Arranging genes from distantly related species -- such as a fish and a mammal -- into groups based on sequence similarities, the team was able to identify the common evolutionary formula that led to pair bonds and co-parenting in the five species that behave monogamously.
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New Species
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January 7, 2019
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https://www.sciencedaily.com/releases/2019/01/190107131214.htm
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New bat-borne virus related to Ebola
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Researchers from Singapore's Duke-NUS Medical School, in collaboration with scientists in China, have identified and characterised a new genus of filovirus from a
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"Studying the genetic diversity and geographic distribution of bat-borne filoviruses is very important for risk assessment and outbreak prevention as this type of infectious disease can affect the general public without warning with devastating consequences," said Professor Wang Lin-Fa, Director of the Emerging Infectious Diseases Signature Research Programme at Duke- NUS Medical School, Singapore, and a senior author of the study.The researchers discovered the new virus while analysing the diversity of filoviruses in The results showed that the Menga virus represents a new genus named Dianlovirus within the filovirus group. The Mengla virus is genetically distinct, sharing just 32 percent to 54 percent of its genetic sequence with other known filoviruses. It is found in different geographic locations compared to other filoviruses. This new genus, which could include more than one species, sits in between Ebola virus and Marburg virus on the evolutionary tree.The researchers tested the Mengla virus in cell lines from various animal species and found that, like other filoviruses, it poses a potential risk of interspecies transmission.The results confirmed that the Mengla virus is evolutionarily closely related to Ebola virus and Marburg virus and shares several important functional similarities with them. For example, the genome organisation of the Mengla virus is consistent with other filoviruses, coding for seven genes. The Mengla virus also uses the same molecular receptor, a protein called NPC1, as Ebola virus and Marburg virus to gain entry into cells and cause infection."The early identification of the filovirus from At present, the virus has only been identified in
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New Species
| 2,019 |
January 3, 2019
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https://www.sciencedaily.com/releases/2019/01/190103120852.htm
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What makes two species different?
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Most evolutionary biologists distinguish one species from another based on reproductivity: members of different species either won't or can't mate with one another, or, if they do, the resulting offspring are often sterile, unviable, or suffer some other sort of reduced fitness.
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For most of the 20th century, scientists believed that this reproductive incompatibility evolved gradually between species as a by-product of adapting to different ecological circumstances: if two species were geographically isolated, they would adapt differences based on their environment. New research conducted at the University of Rochester, in collaboration with the University of Nebraska, shows, however, that there are more factors at play -- specifically the presence of selfish genes called meiotic drive elements, whose flow among species may dictate whether two species converge or diverge. In a new paper published in the journal When two members of a species mate and exchange genetic material, this is known as gene flow. When two members of different species mate, however, gene flow is reduced. "Genes from one species simply can't talk to genes from the other species," says Daven Presgraves, a dean's professor of biology at Rochester. Though the genes may work fine on their own genetic background, when they are moved into the genetic background of another species, they have negative effects. "All of the gene copies in you and me work in the human genome. But if we were to take a gene out of you and stick it in a macaw parrot, they haven't seen this sequence before and it might not work together with the other genes. That would compromise some sort of function like fertility."This is what happened when Presgraves and members of his lab crossed two different species of fruit flies, one from Madagascar and the other from the island of Mauritius. When the two species were crossed, their female hybrid offspring were fertile, but the hybrid male offspring were completely sterile. "One of the steps on the way to complete reproductive isolation is that the XY sex becomes sterile first in that gradual build-up of incompatibility," Presgraves says. In the case of fruit flies, as in human beings, the XY sex is male.Chromosomes are divided into two types: allosomes, or sex chromosomes, and autosomes, or body chromosomes. Genetic traits linked to an organism's sex are passed on through the sex chromosomes. The rest of the genetic hereditary information is passed on through the autosomes. When the researchers mapped the factors that cause hybrid males to become sterile, they found that there were many more incompatibility factors on the X allosome compared to the autosomes. This means that sex chromosomes become functionally different between species much faster than non-sex chromosomes, Presgraves says. "There's a lot more exchange going on between the autosomes than on the X."But what is it that makes sex chromosomes accumulate genetic incompatibility faster than the rest of the genome?The researchers found that a class of "selfish genes" called meiotic drive elements are responsible for making sex chromosomes genetically incompatible at a faster rate. In general, selfish genes are parasites of the genome -- they propagate themselves at the expense of other genes. Meiotic drive elements in particular sabotage the rules of typical inheritance: in normal Mendelian inheritance, a gene is transmitted to half the offspring. Meiotic drive elements, however, manipulate reproduction so they can transmit themselves to more than their fair share of the genome. In hybrid male fruit flies, meiotic drive elements usually kill any sperm that don't carry them, leaving only (or mostly) sperm that do carry the meiotic drive elements."This could be because multiple meiotic drive elements from both parental species are unsuppressed in hybrids, and their combined action causes sterility," says Colin Meiklejohn, a former postdoctoral student in Presgraves's lab.In a twist, however, the researchers also found that if meiotic drive elements are able to experience gene flow, they can also help bring species together. During early speciation, when two different species are just beginning to break away from one another, reproductive incompatibility can be incomplete and "leaky" -- some part of the genome may still be compatible and exchangeable."If two populations are leaky and there is opportunity for gene flow, a selfish gene can leak over into the other population and spread there," Presgraves says. If the species interbreeds and this selfish gene is able to be passed down, instead of becoming incompatible, "that part of the genome will become perfectly exchangeable. In some cases a selfish gene will basically erase the build-up of incompatibilities for a part of the genome."That is, meiotic drive elements can cause incompatibilities between species if they do not experience gene flow, or they can cause a convergence of the species, if they species does experience gene flow. A major factor in determining whether or not a species is compatible hinges on whether or not there is gene flow between the species, Presgraves says. "Species -- even ones that are geographically isolated -- are much leakier than we thought."
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New Species
| 2,019 |
January 3, 2019
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https://www.sciencedaily.com/releases/2019/01/190103110633.htm
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Fruit flies help to shed light on the evolution of metabolism
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Diet choice of animal species is highly variable. Some are specialists feeding only on one food source, such as a sugar-rich fruit or protein-rich meat. Other species, like humans, are generalists that can feed on different kinds of food sources.
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Because of these differences, animal species ingest different amounts of macronutrients, like carbohydrates and amino acids. It is conceivable that the metabolism has to match the diet choice of each species. However, we understand poorly the evolution of animal metabolism -- what are the underlying genetic changes and how these changes define the optimal nutrient composition for a given species.The research group led by Associate Professor Ville Hietakangas at the University of Helsinki have studied the evolution of metabolism by using two very closely related fruit fly species.The first one of them is a generalist, Drosophila simulans, which feeds on varying fruits and vegetables, which typically contain a high amount of sugars. The second one is Drosophila sechellia, which has specialized to feed on one fruit, Noni, Morinda citrifolia, which has low sugar content."We found pretty dramatic metabolic differences between these species. D. sechellia larvae, that are not exposed on sugar in nature, were not able to grow when placed on a sugar-rich diet, while D. simulans had no problems handling dietary sugar," explains Hietakangas.The close relatedness of the fruit fly species allowed the scientist interbreed the species, to make hybrids that were largely genetically like D. sechellia, but contained those genomic regions of D. simulans that were needed for sugar tolerance."The ability to analyze hybrid animals was the key advantage of our study. This way we could not only rely on correlating the findings but were able to identify genetic changes that were causally important. We also could tell that sugar tolerance comes with a cost. D. simulans and the sugar tolerant hybrids survived poorly on a low nutrient diet. This suggests that D. sechellia has evolved to survive on a low nutrient environment, which has required rewiring the metabolism in a way that has made feeding on high sugar impossible," says Hietakangas.This study opens up many interesting questions, also related to humans. In the future, it will be interesting to explore whether human populations that have different dietary histories, for example experiencing extremely limited nutrition for many generations, may respond differently to modern diets rich in sugars.
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New Species
| 2,019 |
January 3, 2019
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https://www.sciencedaily.com/releases/2019/01/190103110608.htm
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Extraordinary treefrog discovered in the Andes of Ecuador
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A new treefrog species was discovered during a two-week expedition to a remote tabletop mountain at Cordillera del Cóndor, a largely unexplored range in the eastern Andes.
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"To reach the tabletop, we walked two days along a steep terrain. Then, between sweat and exhaustion, we arrived to the tabletop where we found a dwarf forest. The rivers had blackwater and the frogs were sitting along them, on branches of brown shrubs similar in color to the frogs' own. The frogs were difficult to find, because they blended with their background," Alex Achig, one of the field biologists who discovered the new species comments on the hardships of the expedition.Curiously, the frog has an extraordinary, enlarged claw-like structure located at the base of the thumb. Its function is unknown, but it could be that it is used either as a defence against predators or as a weapon in fights between competing males.Having conducted analyses of genetic and morphologic data, scientists Santiago R. Ron, Marcel Caminer, Andrea Varela, and Diego Almeida from the Catholic University of Ecuador concluded that the frog represented a previously unknown species. It was recently described in the open-access journal The species name, Despite being newly described,
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New Species
| 2,019 |
December 25, 2018
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https://www.sciencedaily.com/releases/2018/12/181225162815.htm
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Trees' 'enemies' help tropical forests maintain their biodiversity
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Scientists have long struggled to explain how tropical forests can maintain their staggering diversity of trees without having a handful of species take over -- or having many other species die out.
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The answer, researchers say, lies in the soil found near individual trees, where natural "enemies" of tree species reside. These enemies, including fungi and arthropods, attack and kill many of the seeds and seedlings near the host tree, preventing local recruitment of trees of that same species.Also playing a key role in the tropical forest dynamic are seed dispersers. Seeds from individual trees that are carried a distance away -- often by rodents, mammals or birds -- have a chance to get established because the fungi and arthropods in the new region target different species. This restriction of tree recruitment near the adult trees creates a long-term stabilizing effect that favors rare species and hinders common ones, the researchers say.Overturning previous theory, the researchers demonstrate that these interactions with enemies are important enough to maintain the incredible diversity of tropical forests. Results of the study are being published this week in "In many North American forests, trees compete for space and some have a niche that allows them to outcompete others," said Taal Levi, an Oregon State University ecologist and lead author on the study. "Douglas-firs are the species that grow best after a fire. Hemlock thrives in the shade and grows well under a canopy. Some species do well at elevation."But in the tropics, all of the tree species appear to have a similar competitive advantage. There is an abundance of species, but few individuals of each species. The chances of blinking out should be high. But there has to be a mechanism that keeps one species from becoming common, becoming dominant. And it is these natural enemies that have a high host-specificity."Egbert Leigh, of the Smithsonian Tropical Research Institute, best described the diversity of tropical forests in one statement: "How can a half square-kilometer (of forest) in Borneo or Amazonia contain as many tree species as 4.2 million kilometers of temperate zone forest in Europe, North American and Asia combined?"Levi said some tropical forests have as many as 1,000 different tree species living in the same general area. The idea of natural enemies restricting the recruitment of juvenile trees is not new, he said, and in fact was posited nearly a half-century ago by two scientists in what has become known as the Janzen-Connell hypothesis.Although Janzen-Connell effects should prevent one species from taking over, they don't explain or predict how a thousand tree species can be maintained together. In fact, previous researchers suggested that the Janzen-Connell effects could only maintain a very few species, and thus were relatively unimportant to the overall maintenance of tropical forest diversity.Instead, Levi and his colleagues from the University of Florida, Oregon State, and James Cook University in Australia says this close relationship between trees and their natural enemies is the key to tropical forest diversity. They found that if fungi, arthropods and other natural enemies produce even small zones around trees where a new tree of the same species cannot establish, then the very high levels of tree diversity observed in tropical forests can be maintained almost indefinitely."There is a 'seed shadow' around adult trees and some escape the curve and get out, allowing recruitment in other areas until the host-specific enemies get established in the new location," Levi said. "That's why it is critically important to maintain the biodiversity of birds and mammals in these forests, or recruitment eventually will decline -- especially in over-hunted areas."Levi is in Oregon State's Department of Fisheries and Wildlife, in the College of Agricultural Sciences.
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New Species
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December 22, 2018
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https://www.sciencedaily.com/releases/2018/12/181222180746.htm
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Howler monkey study examines mechanisms of new species formation
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A new University of Michigan study of interbreeding between two species of howler monkeys in Mexico is yielding insights into the forces that drive the evolution of new species.
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How do new species emerge in nature? One common but overly simplified version of the story goes like this: A population of animals or plants becomes geographically isolated -- by a river that changes course or a mountain range that rises up, for example -- and the two separated groups accumulate genetic differences over time as they adapt to their environments in isolation.Eventually, the DNA of the two groups is so different that the two populations are considered distinct species. Voilà, speciation has occurred.In reality, the process is much more complex than that. While geographic isolation can start the speciation process, evolutionary biologists believe that other forces -- including various forms of natural selection -- can help to complete it.The new U-M study provides rare empirical evidence that multiple forms of natural selection, including a contentious one called reinforcement, are helping to complete the speciation process in a natural howler monkey "hybrid zone," a place where the two species coexist and occasionally interbreed in a process called hybridization.The study is scheduled for online publication Dec. 22 in the journal Molecular Ecology. In the paper, the researchers use the primate hybrid zone to identify parts of the genome that are likely to contain genes underlying speciation and to test for signals of the selection forces that shaped them."We observed patterns in the genetic data suggesting that hybridization is playing a direct role in completing the speciation process by enhancing genetic differences between species," said U-M doctoral candidate Marcella Baiz, the study's first author. The other authors are Liliana Cortés-Ortiz and Priscilla Tucker of the U-M Department of Ecology and Evolutionary Biology."We found a signal for multiple forms of natural selection driving species differences, including reinforcement, a process that has been highly debated," Baiz said. "This result is particularly notable because empirical evidence for reinforcement is extremely rare, especially genetic evidence."The two species at the center of the study, mantled howler monkeys and black howler monkeys, diverged about 3 million years ago and lived apart until relatively recently when they came into contact again -- perhaps within the last 10,000 years -- in a roughly 12-mile-wide hybrid zone in the southeastern Mexican state of Tabasco.A species was once defined as a group of actually or potentially interbreeding individuals that are reproductively isolated from other such groups. The concept of reproductive isolation is key to that definition and means that despite any hybridization, true species maintain their uniqueness.However, the modern view of what a species is does not require full reproductive isolation, and hybridization has been discovered to be quite common in nature.At the howler monkey hybrid zone in Mexico where U-M's Cortés-Ortiz and her colleagues have worked for about two decades, analysis of DNA samples has confirmed that black and mantled howler monkeys interbreed and produce hybrid offspring. The fact that hybridization is occurring between the two groups means that reproductive isolation is incomplete.Evolutionary biologists believe that various natural selection pressures can help complete the process by strengthening barriers to gene flow between two groups, pushing them toward full reproductive isolation.And because natural selection favors organisms that successfully reproduce over those that don't, it is biased against hybrids, which sometimes die before reproducing or are simply incapable of reproducing.Natural selection tries to block the formation of these "unfit" hybrids. One way to do that is to gradually increase the genetic differences between two groups of organisms -- in this case black and mantled howler monkeys -- so that it's more difficult for them to mate and to produce hybrid offspring.While working to thwart the formation of hybrids in this way, natural selection strengthens reproductive isolation by increasing genetic differences. This process is called reinforcement; while the idea has been around for more than a century, empirical evidence to support it is scarce.To test for the presence of reinforcement, Baiz and her colleagues compared the DNA of black and mantled howler monkeys living the Tabasco hybrid zone to the DNA of black and mantled howler monkeys living far from the hybrid zone.If reinforcement is working to thwart hybridization and to strengthen reproductive isolation, then the genetic differences between the two species in the hybrid zone should be greater than the genetic differences between monkeys of these two species living on either side of the hybrid zone.And that's exactly what Baiz and her colleagues found when they compared genetic markers that are at or near genes likely associated with reproductive isolation."Speciation is a complex process that can be driven by direct and indirect mechanisms that interact to maintain and strengthen the process, and this study is one of the few natural examples that documents this," Baiz said.
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New Species
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December 21, 2018
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https://www.sciencedaily.com/releases/2018/12/181221123911.htm
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Female penises evolved twice in bark lice
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In a group of bark lice, a penis has evolved twice -- in the females. In their nutrient-scarce environment, "seminal gifts" are an incentive for females to force mating, leading to the co-evolution of female penises and male vaginas.
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Two geographically distinct genera of the bark lice, The bark lice live in caves that offer extremely scarce sources of nourishment. This gives females an incentive for repeated mating, since the 'seminal gift' from males is rich in nutrients. In addition, long mating times of up to 70 hours require females to grasp and stimulate their partners, sometimes even through coercion."Of course, one of the important functions of penis and vagina is probably the secure delivery of semen in non-aquatic environments," Yoshizawa explains. "However, I think sexual selection is a more important factor for the evolution of the 'male' penis, because not all terrestrial animals possess it. For example, many birds do not have a penis. Under typical sexual selection in which females are choosy and males are courting, the male penis has evolved many times independently, probably for active and sometimes coercive mating. A simple reversal of gender roles in sexual selection, however, cannot simply cause the reversed genital organs." In their study, they argue that it is their scarce environment and the competition for male seminal gifts that drove the evolution of female penises in these two groups of bark lice.The researchers noted that one species of To test hypotheses linking sexual selection pressures, specific environments, and the evolution of penises, it is insightful to study the conditions of species with reversed sexual organs. In the words of Yoshizawa: "The study of female penises could also shed light on the evolution of male penises."
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New Species
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December 20, 2018
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https://www.sciencedaily.com/releases/2018/12/181220104705.htm
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Spectacular flying reptiles soared over Britain's tropical Jurassic past
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Spectacular flying reptiles armed with long teeth and claws which once dominated the skies have been rediscovered, thanks to a palaeontology student's PhD research.
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Dr Michael O'Sullivan, at the University of Portsmouth, has uncovered evidence of well armed and substantial flying reptiles from historically important, but overlooked, British Jurassic fossils.He's also found a new species of pterosaur with a wingspan of two metres -- as large as a modern mute swan, and a giant in its time.Some 200 fossils of flying reptiles -- pterosaurs -- have been collected over the last two centuries from the Stonesfield Slate, but their significance has been long neglected by palaeontologists, probably because they are mere fragments.Closer inspection has revealed evidence of multiple pterosaur lineages in the UK's Jurassic past, including some unexpectedly large and formidably armed species.The research is Published in Dr O'Sullivan, in the University's School of Earth and Environmental Sciences, said: "It's large fangs would have meshed together to form a toothy cage, from which little could escape once "The excellent marine reptiles and ammonites of the UK's Jurassic heritage are widely known, but we celebrate our Jurassic flying reptiles far less."The Stonesfield pterosaurs are rarely pretty or spectacular, but they capture a time in flying reptile evolution which is poorly represented globally. They have an important role to play in not only understanding the UK's natural history, but help us understand the bigger global picture as well."He has named the new species The generic name means 'cage tooth', in reference to its huge, fang-like teeth -- up to 26mm long at a time when few pterosaurs had any teeth -- and the species name honours comic book artist Nick Roche in recognition of the role popular media has in how extinct animals are portrayed.Only the lower jaw of Much of Dr O'Sullivan's research has involved untangling the messy science associated with these neglected specimens.He said: "Dr O'Sullivan was examining the Stonesfield pterosaur collections held in museums across the UK for his PhD studies when he found evidence of three distinct types of pterosaur, some of which are the oldest of their kind, as well as evidence of a new pterosaur species.Stonesfield Slate, where the new pterosaur fossils were found, is a rich source of Jurassic fossils about 10 miles northwest of Oxford. It is where, in 1824, Britain's first discovered dinosaur, the The quantity and quality of such fossils from the area might be why these fragments have until now been overlooked.
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New Species
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December 19, 2018
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https://www.sciencedaily.com/releases/2018/12/181219115600.htm
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450 fossilized millipedes found in 100-million-year-old amber
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Since the success of the Jurassic Park film series, it is widely known that insects from the Age of the Dinosaurs can be found exceptionally well preserved in amber, which is in fact fossilised tree resin.
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Especially diverse is the animal fauna preserved in Cretaceous amber from Myanmar (Burma). Over the last few years, the almost 100-million-year-old amber has revealed some spectacular discoveries, including dinosaur feathers, a complete dinosaur tail, unknown groups of spiders and several long extinct groups of insects.However, as few as three millipede species, preserved in Burmese amber, had been found prior to the study of Thomas Wesener and his PhD student Leif Moritz at the Zoological Research Museum Alexander Koenig -- Leibniz Institute for Animal Biodiversity (ZFMK). Their research was recently published in the open-access journal Having identified over 450 millipedes preserved in the Burmese amber, the scientists confirmed species representing as many as 13 out of the 16 main orders walking the Earth today. The oldest known fossils for half of these orders were found within the studied amber.The researchers conducted their analysis with the help of micro-computed tomography (micro-CT). This scanning technology uses omni-directional X-rays to create a 3D image of the specimen, which can then be virtually removed from the amber and digitally examined.The studied amber is mostly borrowed from private collections, including the largest European one, held by Patrick Müller from Käshofen. There are thought to be many additional, scientifically important specimens, perhaps even thousands of them, currently inaccessible in private collections in China.Over the next few years, the newly discovered specimens will be carefully described and compared to extant species in order to identify what morphological changes have occurred in the last 100 million years and pinpoint the speciation events in the millipede Tree of Life. As a result, science will be finally looking at solving long-standing mysteries, such as whether the local millipede diversity in the southern Alps of Italy or on the island of Madagascar is the result of evolutionary processes which have taken place one, ten or more than 100-million years ago.According to the scientists, most of the Cretaceous millipedes found in the amber do not differ significantly from the species found in Southeast Asia nowadays, which is an indication of the old age of the extant millipede lineages.On the other hand, the diversity of the different orders seems to have changed drastically. For example, during the Age of the Dinosaurs, the group Colobognatha -- millipedes characterised by their unusual elongated heads which have evolved to suck in liquid food -- used to be very common. In contrast, with over 12,000 millipede species living today, there are only 500 colobognaths.Another curious finding was the discovery of freshly hatched, eight-legged juveniles, which indicated that the animals lived and reproduced in the resin-producing trees."Even before the arachnids and insects, and far ahead of the first vertebrates, the leaf litter-eating millipedes were the first animals to leave their mark on land more than 400-million-years ago," explain the scientists. "These early millipedes differed quite strongly from the ones living today -- they would often be much larger and many had very large eyes."The larger species in the genus Arthropleura, for example, would grow up to 2 m (6.5 ft) long and 50-80 cm (2-3 ft) wide -- the largest arthropods to have ever crawled on Earth. Why these giants became extinct and those other orders survived remains unknown, partly because only a handful of usually badly preserved fossils from the whole Mesozoic era (252-66-million years ago) has been retrieved. Similarly, although it had long been suspected that the 16 modern millipede orders must be very old, a fossil record to support this assumption was missing.
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New Species
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December 18, 2018
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https://www.sciencedaily.com/releases/2018/12/181218115224.htm
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Broading the biodiversity catalogue of spider populations in the Iberian Peninsula
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The new study, covering the largest study area on this animal group in peninsular territory, is now published in the journal
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The scientific team has studied a total of 20,539 samples of different Iberian spider species -with 8,521 adult specimens corresponding to 190 genera, 39 families and 376 species- in the oak woodlands of National Parks in Aiguestortes i Estany de Sant Maurici, Ordesa i Mont Perdut, the Peaks of Europe, Monfragüe, Cabañeros and Sierra Nevada.These forests with temperate climate -where arboreal species and deciduous trees are abundant- represent the most appropriate natural habitat "to study the biogeographic patterns of spiders at a peninsular scale," says Professor Miquel Àngel Arnedo. "In a broader sense, oak woodlands are a few of the forest communities that are represented in all National Parks building up our study. These are natural habitats of interest regarding conservation, and show a high level of endemism and their evolutionary history is quite well known."The degree of knowledge on the geographic distribution of Iberian spiders is still very little compared to other Mediterranean countries. "The lack of tradition in natural history studies in the country and the reduced amount of admirers of arachnology could explain these differences," says Arnedo, member of the Department of Evolutionary Biology, Ecology and Environmental Sciences of the Faculty of Biology and IRBio.The research team has found eleven new spider species -so far more than 1,300 species were known in the peninsula and the Balearic Islands- apart from other twenty species whose taxonomic identification is still pending. According to the experts, some of the new species could be especially vulnerable to the environmental factors (in most of the cases, only one or a few individuals have been discovered in one geographical place or even one parcel).Moreover, the experts add seven new spider species to the peninsular biological inventory -and three more in the Spain- with the identification in the area of species such as "There are still many spider species to be found," adds Arnedo. "These results show there is a lack of systematic samplings in the arachnological biodiversity in Spain and are a good example of the few things we know about our own fauna."The sampling technique for spider specimens in the natural environment has followed the standardized protocol COBRA. This methodology -applied in studies of terrestrial arthropod communities worldwide- enables researchers to create an inventory of the species in a specific area and brings data to extrapolate the amount and abundance of species that can live in a geographical area.Moreover, the methodology based on content such as DNA barcoding -that is, the use of a short and standardized DNA fragment as the identifier of a species- is the innovating technique for applied comparative genetics to speed up the identification of species and improve the resolution of the analysis of biodiversity in this animal group. "This methodology enables developing high-resolution bioinformatic tools to help automatizing the classification and identification of species, even in populations of the same species in different places," says Arnedo."For instance, young individuals cannot be classified as species through morphological criteria, which in many cases they only reach the family taxon. With the DNA barcoding we can categorize them under specific species. This technique also helps to identify different vital stages in the same species -even remains such as exuvia or overlayers, excrements or environmental DNA- which would be impossible to distinguish otherwise.Loss of natural habitat, invasive species, environmental pollution and global warming are threats that put the conservation of peninsular arachnological fauna in danger. Some spider species tolerate environmental perturbations better than others -these are generalist predators and adapt to changes- but other groups are more sensitive to environmental factors. In the future, samplings will need standardized protocols and wider taxonomical data with nuclear molecular markers, the morphological studies and ecological information as well to know about the evolutionary and biogeographic history of peninsular spiders to guarantee their conservation."Like the other organisms, spiders are submitted to variations in their environmental and biological environment. We are all in the same boat and with the same destination, the difference is that we are the in charge of this destiny," concludes Professor Miquel Àngel Arnedo.
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New Species
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December 18, 2018
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https://www.sciencedaily.com/releases/2018/12/181218115205.htm
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Fossils suggest flowers originated 50 million years earlier than thought
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Scientists have described a fossil plant species that suggests flowers bloomed in the Early Jurassic, more than 174 million years ago, according to new research in the open-access journal
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Before now, angiosperms (flowering plants) were thought to have a history of no more than 130 million years. The discovery of the novel flower species, which the study authors named Angiosperms are an important member of the plant kingdom, and their origin has been the topic of long-standing debate among evolutionary biologists. Many previously thought angiosperms could be no more than 130 million years old. However, molecular clocks have indicated that they must be older than this. Until now, there has been no convincing fossil-based evidence to prove that they existed further back in time."Researchers were not certain where and how flowers came into existence because it seems that many flowers just popped up in the Cretaceous from nowhere," explains lead author Qiang Fu, Associate Research Professor at the Nanjing Institute of Geology and Paleontology, China. "Studying fossil flowers, especially those from earlier geologic periods, is the only reliable way to get an answer to these questions."The team studied 264 specimens of 198 individual flowers preserved on 34 rock slabs from the South Xiangshan Formation -- an outcrop of rocks in the Nanjing region of China renowned for bearing fossils from the Early Jurassic epoch. The abundance of fossil samples used in the study allowed the researchers to dissect some of them and study them with sophisticated microscopy, providing high-resolution pictures of the flowers from different angles and magnifications. They then used this detailed information about the shape and structure of the different fossil flowers to reconstruct the features of The key feature of an angiosperm is 'angio-ovuly' -- the presence of fully enclosed ovules, which are precursors of seeds before pollination. In the current study, the reconstructed flower was found to have a cup-form receptacle and ovarian roof that together enclose the ovules/seeds. This was a crucial discovery, because the presence of this feature confirmed the flower's status as an angiosperm. Although there have been reports of angiosperms from the Middle-Late Jurassic epochs in northeastern China, there are structural features of Having made this discovery, the team now wants to understand whether angiosperms are either monophyletic -- which would mean "The origin of angiosperms has long been an academic 'headache' for many botanists," concludes senior author Xin Wang, Research Professor at the Nanjing Institute of Geology and Paleontology. "Our discovery has moved the botany field forward and will allow a better understanding of angiosperms, which in turn will enhance our ability to efficiently use and look after our planet's plant-based resources."
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New Species
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December 6, 2018
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https://www.sciencedaily.com/releases/2018/12/181206114702.htm
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Could algae that are 'poor-providers' help corals come back after bleaching?
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How much of the ability of a coral reef to withstand stressful conditions is influenced by the type of algae that the corals hosts?
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Corals are marine invertebrates from the phylum called cnidarians that build large exoskeletons from which colorful reefs are constructed. But this reef-building is only possible because of a mutually beneficial relationship between the coral and various species of single-celled algae called dinoflagellates that live inside the cells of coral polyps.The algae are photosynthetic -- meaning capable of converting the Sun's energy into chemical energy for food, just like plants. And the exchange of nutrients between the coral and the algae is essential for healthy reef communities. The coral provides the algae with carbon dioxide, nitrogen, and other compounds that they need to survive and perform photosynthesis. The algae, in turn, can stimulate the growth of the coral by providing them with sugars and fats, which are created via photosynthesis.An international research team based in New Zealand and including Carnegie's Arthur Grossman set out to determine how the abundance and diversity of sugars and other carbon compounds shared with the coral varies between species of algae and what this could mean for a coral's ability to survive under stressful conditions caused by climate change. They did this by studying the anemone Aiptasia -- a cnidarian like the coral -- which can also host symbiotic dinoflagellates, but it grows much faster and is easier to study than corals.Their findings are published by "We're very interested in what happens when external conditions force corals to switch from hosting one symbiotic algal species to another," Grossman said. "Having a long-term symbiotic relationship with a native algal species is advantageous to the coral. But if the surrounding conditions are altered by climate change, could a different algal species confer corals with improved fitness and chances of survival?"When comparing the sugars, fatty acids, and other metabolic products transferred to the host anemone by two different species of algae -- one native, the other a transplant that's not normally found in the anemone host -- the team found that the native species consistently provided more nutrition to the anemone than the non-native one.However, the transplanted "poor provider" algae used in this research, called Durusdinium trenchii, is known to have a high heat resistance and it's been observed to repopulate coral communities that have been damaged by bleaching and have lost their original algal tenants."Under normal conditions, coral or anemones that host a species of algae that's a poor nutrient provider will be forced to burn its own energy stores and take in nutrition from the surrounding water," Grossman explained. "But in the wake of a bleaching event, even a poor provider may be better than no provider."Further research that involves a greater variety of algae and studies the flow of nutrients between the organisms in greater detail is necessary to fully understand if more heat tolerant but less generous algal species might help these fragile ecosystems survive a world in which the climate is rapidly changing.
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New Species
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December 5, 2018
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https://www.sciencedaily.com/releases/2018/12/181205134047.htm
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30 years of experimental evolution results in a new sex chromosome
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The laboratory of Professor Axel Meyer, University of Konstanz has published new findings of an experimental evolutionary project that ran for 30 years on the genomic mechanisms of sex determination in swordtail fish in the journal
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The diversity of sex determination systems is remarkably diverse among fishes compared to mammals that all have a stereotypic XX, XY sex-chromosomal mechanism to determine sex. Why and how the genomic mechanisms and the evolutionary causes behind such diversity in sex determination in fish are so variable remained unknown. Evolutionary biologist Dr Paolo Franchini with his collaborators has now been able to describe such a mechanism and its exact function in this study entitled "Long-term experimental hybridisation results in the evolution of a new sex chromosome in swordtail fish."Professor Manfred Schartl, Head of the Department for Physiological Chemistry at the Biocenter of the University of Würzburg, initiated this experiment that included hybridisation with backcrossing by two Xiphophorus fish species with different sex chromosome systems three decades ago. Hybrid origins of species, the result of the crossing of two genetically different species, are found frequently in fish populations."What we know from the study of these systems in natural habitats is that hybridisation is a crucial mechanism for the evolution of new species," explains Paolo Franchini.In the experiment the researchers could study the effects of hybridisation on the genomic mechanism of sex-determination. Determining the sex of these fish is easy: as its name suggests, the male swordtail fish has a sword-like elongated caudal fin; the female, on the other hand, is rounder and fuller and does not have a swordtail. In this long-term laboratory study the effects of hybridisation that is thought to have resulted in at least two swordtail species in nature on the genome and the mechanisms that determine sex could be studied in detail.In an experimental design that makes it possible to track crossings of more than 100 generations over more than 30 years, a female Paolo Franchini explains further: "We found out that introgression -- the movement of genetic material from one species to another -- and the selection of pigmentation phenotypes results in the retention of an unexpectedly large maternally derived genomic region." During the hybridisation process, the sex-determining region on the X chromosome of one parent was transferred to an autosome of the hybrid fish. This transfer led to the evolution of a completely new sex chromosome. "Our results show above all the complexity of factors that contribute to patterns observed in hybrid genomes including such fundamental issues such as sex determination," summarises Paolo Franchini. The work proves that hybridisation can catalyse the rapid evolution of a new sex chromosome and thus makes an essential contribution to an experiment launched more than 30 years ago.
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New Species
| 2,018 |
December 5, 2018
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https://www.sciencedaily.com/releases/2018/12/181205133918.htm
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New butterfly named for pioneering 17th-century entomologist Maria Sibylla Merian
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More than two centuries before initiatives to increase the number of women in STEM fields, 52-year-old Maria Sibylla Merian sailed across the Atlantic on a largely self-funded scientific expedition to document the animals and plants of Dutch Suriname.
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Born in Germany in 1647, Merian was a professional artist and naturalist whose close observations and illustrations were the first to accurately portray the metamorphosis of butterflies and moths and emphasize the intimate relationship between insects and their host plants.Now, a new Central American butterfly species has been named in her honor.Catasticta sibyllae is a rare, black butterfly known from only two male specimens found in Panama decades apart. One had been stowed, unidentified, in a drawer at the Smithsonian National Museum of Natural History since the 1980s. The other was collected in May."Since this is such a distinctive butterfly, we wanted to name it after someone who would deserve it," said Shinichi Nakahara, the study's lead author and a Lepidopterist at the Florida Museum of Natural History. "Merian was centuries ahead of her time, and her discoveries changed the course of entomology. The fact that she accomplished so much against all odds -- as a divorced woman in the 17th century who taught herself natural history -- is remarkable. And she did it so beautifully."Two subspecies of butterflies have previously been named for Merian, but to Nakahara's knowledge, this is the first butterfly species named in her honor.Her other namesakes include the Cuban sphinx moth, a species of cane toad, a snail, the Argentine black-and-white tegu lizard, a bird-eating spider, a genus of praying mantises, a genus of exotic flowering plants, a bug, the African stonechat bird and a species of bugle lily.But Merian's first love was butterflies and moths, and like many entomologists, the obsession struck early. She began collecting insects in her youth and raised silkworms as a teenager. After realizing that other caterpillars also produced beautiful butterflies or moths, "this led me to collect all the caterpillars I could find in order to observe their appearance," she wrote.Artistically trained by her stepfather, a still-life painter, she drew and painted her observations, publishing her first book of illustrations at age 28 and following this with a two-volume set on caterpillars that showed the metamorphosis and host plants of 186 species. At a time when many naturalists believed insects were the products of spontaneous generation, Merian's work was the first to show their complete life cycles, from eggs to adults.While collecting butterflies was a common hobby for women of Merian's class and era, science was reserved for men. Nevertheless, Merian was not content to merely illustrate live insects but also noted their habits, life stages and interactions with other species. A self-taught scholar, she learned Latin and studied natural history while living with a religious sect for several years, and after her marriage ended, she earned a livelihood by selling her artwork.She carefully recorded and depicted hundreds of species, several decades before Carl Linnaeus introduced the modern system of scientific classification. Linnaeus and other scientists would later use Merian's descriptions to name and describe about 100 species.Amsterdam granted her a permit to travel to the then-Dutch colony of Suriname in 1699, and she sold 255 of her paintings to underwrite the expedition. Her subsequent volume on Suriname's flora and fauna described 60 species of plants, including the pineapple, and more than 90 species of animals. Notably, she often illustrated animals in their ecological context, depicting leafcutter ants defoliating a plant and a tarantula feeding on a hummingbird.The artwork in her Suriname study journal was executed with such detail and accuracy that modern entomologists could identify 73 percent of the butterflies and moths to genus and 56 percent to species.Notably, Merian also published works in German and Dutch, which allowed lay readers unprecedented access to scientific discoveries, arguably making her one of the earliest science communicators.When Nakahara learned about Merian's significant contributions to entomology, he thought "she would be a very good person to name this unique butterfly after," he said.The butterfly first came to Nakahara's attention via former University of Florida graduate student Pablo Sebastián Padrón, who was examining the Smithsonian's collection of pierid butterflies when he came across an unusual specimen he could not identify. He snapped a picture and sent it to Nakahara at the Florida Museum's McGuire Center for Lepidoptera and Biodiversity.Nakahara drew a blank."I didn't know what it was," he said. "I told him it could be a new species, but it looked so bizarre. It could have been an aberration. We just wanted to wait for an additional specimen."Most Pieridae, a large family of butterflies, are colorful with a wide variety of wing patterns, Nakahara said. But Catasticta sibyllae is a dramatic black with simple rows of white dots lining its wings and tiny flares of red where the wings join its body. Several physical characteristics marked it as a pierid, but the coloring was unlike any other pierid species Nakahara or Padrón had seen.By a stroke of luck, Mississippi State University entomologist John MacDonald found a second example just a couple of months later. Not knowing of Padrón's specimen, he sent Nakahara a photo of the same species from a collecting trip in Panama."The first thought that came to my mind was that we could sequence its DNA," Nakahara said. "I immediately wrote back and was like, 'Hey, can you send me a leg?'"The DNA extracted from the leg confirmed that the two pierid specimens were an undescribed species. Both were found at lower elevations, outside of the family's usual Andean range, and both males were alone, unusual for butterflies in the Catasticta genus, which tend to congregate in groups.The researchers found no other C. sibyllae specimens in 14 museum collections, and MacDonald's 29-month survey of the area where the second specimen was collected did not uncover any other examples, suggesting the species is extremely rare."Perhaps another scientific expedition is warranted," Nakahara said.
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New Species
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December 5, 2018
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https://www.sciencedaily.com/releases/2018/12/181205171915.htm
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Weirdly shaped mouse sperm can be used to tell species apart
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Think back to health class and picture a sperm. It's got a smooth rounded head, with a long skinny tail at the end, right? As it turns out, the sperm from different species of animals have different shapes -- and, as a new study in the
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"In this paper, we looked at the shape of sperm in 18 different species of rodents, and we found that sperm shape is a characteristic that can be used to discriminate between closely related mammal species," says Noé de la Sancha, co-first author of the paper and a researcher at the Field Museum in Chicago. "This is the biggest study for this kind of rodent, this is brand spankin' new."To come to their conclusions, de la Sancha and his fellow first author, Luis Rossi of the Universidad de Buenos Aires, had to look at a lot of sperm. They analyzed upwards of 50 individual spermatozoa from 58 individual South American rodents from the subfamily Sigmodontinae of the family Cricetidae, and for that, they needed a lot of pickled mouse testicles."I trapped a lot of these mice when I was working on my dissertation. When we prepared the male specimens, we put the testicles in formalin, and that preserved the sperm," says de la Sancha. "A lot of people throw the testes away -- they're an underutilized resource."Rossi and de la Sancha were then able to study the preserved sperm, taking measurements and observing differences in shape and size. They discovered that the sperm varied quite a bit, even in very closely related species. Some had hooked heads, like the top of a soft-serve ice cream cone, while others were rounded and smooth, and their tails were different sizes. The most variation was found in the sperms' mid-sections, which are packed with energy-producing mitochondria that power the sperm to swim."The biggest surprise was that the sperm shapes didn't group the way we thought they would," says de la Sancha. "You'd expect the sperm of closely related species to be really similar to each other, but they discriminate really nicely. Sometimes the sperm from distantly related species looked more alike than the sperm from close relatives."It's not exactly clear why the different species have such differently-shaped sperm, but co-author Rossi hypothesizes that the different sperm shapes must be conferring some sort of advantage to the rodents. "Sperm competition is a form of post-coital sexual selection that influences the evolution of the semen characteristics of animals," explains Rossi. "This work represents an important step in our understanding of how evolutionary advances can maximize reproductive success. Looking at the sperm also lets us see if the shape can be traced back to the evolutionary relationships between species -- what biologists call a phylogenetic signal."The research begs the question, "Surely there's an easier way to tell these animals apart than by examining their sperm?" Not necessarily, says de la Sancha. "Many of these species are cryptic -- they look nearly identical, even to experts," he explains. "And using DNA to tell species apart isn't perfect, either. You can tell by DNA that two specimens are different from each other, but how different is different enough to be a separate species? Is it just geographic variation? For many closely related species, it's not that straightforward."But while two rodents' DNA might be very close and they might look the same, their sperm might have completely different shapes -- a dead giveaway that they belong to separate species. "This adds another level of evidence for telling species apart, just like the shape of their teeth or the length of their tails," says de la Sancha.And telling these rodents apart could have important implications for medicine and conservation, says de la Sancha. "Some of these species of mice are hosts of specific diseases," he explains. "The more accurately we can determine which specimens belong to which species, the better we can fight the spread of those diseases."Distinguishing between species is also crucial for researchers working to protect those species. "We still don't know how many species are on the planet right now, and we're in the sixth mass extinction. We're losing species faster than we can identify new ones," says de la Sancha. "This study could make us better able to understand bigger patterns of biodiversity. Using sperm to tell rodents apart is adding one more tool to the toolbox."
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New Species
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December 5, 2018
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https://www.sciencedaily.com/releases/2018/12/181205093726.htm
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Mystery of color patterns of reef fish solved
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Scientists have solved the mystery of why some closely-related species of an iconic reef fish have vastly different colour patterns, while others look very similar.
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Innovative research led by scientists at the ARC Centre of Excellence for Coral Reef Studies based at James Cook University, examined the differences in appearance of 42 species of the butterflyfish.They found that on reefs where closely related butterflyfish species ranges overlap, the differences in colour patterns between the two were most pronounced.The team used high-resolution digital colour photographs to quantify colour patterns and explore how they were influenced by evolutionary processes."Our results show that, over millions of years, butterflyfishes have evolved the greatest diversity of visual markings when they live in the same area as other, closely related species," said lead author and PhD student Christopher Hemingson."Crucially, we also found that this only happens when both species have ranges that are of similar sizes," said Mr Hemingson."We were surprised to find that when one species' range is a lot larger than the neighbouring species, the pattern is reversed -- with the colour pattern of overlapping species found to be less different," said co-author Dr Peter Cowman.Professor David Bellwood, a co-author and senior investigator, noted that this is the first time geographic range dynamics have been shown to be an important predictor of colour differences among marine fish species."This research is the first of its kind to quantify colour and pattern differences simultaneously among butterflyfish species. It showed us that colour pattern differences can evolve very quickly among species (within 300,000 years) but then remain stable over millions of years," said Professor Bellwood."Colour is far more complicated than just looking different from other species," said Mr Hemingson."These colour patterns also depend specifically on what other species are also present. It is an interesting piece to the puzzle and may help explain why reef fishes are so colourful."
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New Species
| 2,018 |
December 4, 2018
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https://www.sciencedaily.com/releases/2018/12/181204090325.htm
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Think about bees, say researchers, as Grand-Staircase Escalante National Monument Shrinks
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The state of Utah's nickname is "The Beehive State," and the moniker couldn't be more apt, say Utah State University scientists. One out of every four bee species in the United States is found In Utah and the arid, western state is home to more bee species than most states in the nation. About half of those species dwell within the original boundaries of the newly reduced Grand Staircase-Escalante National Monument.
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"The monument is a hotspot of bee diversity," says USU-Tooele entomologist Joseph Wilson, associate professor in USU's Department of Biology, who, with scientist and USU alum Olivia Messinger Carril, USDA entomologist Terry Griswold and USU emeritus professor James Haefner, reported 660 species identified in the protected region in the November 7, 2018 issue of Now, in a follow-up paper published Dec. 4, 2018, in the same journal, Wilson, Carril and New York-based free-lance journalist Matt Kelly, examine data on the 660 species to focus on what the newly reduced monument boundaries mean for the pollinators left out of protected areas.It's been exactly year, since President Donald Trump announced, in Salt Lake City, his intention to sharply reduce Utah's Grand Staircase-Escalante and Bears Ears National Monuments. What does this mean for pollinators inhabiting those areas?"That's exactly the question that should be asked, that's not being asked," says Wilson, lead author of the latter paper. "So that's what my co-authors and I, using data from the first paper, have examined."The good news is 87 percent of the 660 species identified by the USU scientists are found in the newly reduced boundaries of GSENM."But that leaves about 84 species no longer inhabiting protected land," Wilson says. "This includes some new, undescribed species, as well as 'morphospecies,' which are unique individuals that don't match known species."Further, he says, some species known only in the Mojave Desert are among the pollinators found in the now unprotected area."This is significant because these are 'edge' populations," Wilson says. "That is, in the face of climate change, they could be the first to go extinct as the region gets hotter and drier, or the area could provide a refuge for populations of the same species now inhabiting the Mojave desert."A broader concern, he says, is the lack of consideration of pollinators in the monument's new management plans."Will the reduction in monument size affect the pollinators?" Wilson asks. "We don't know. But if development is allowed in the unprotected areas, say, mining, road development, more recreational development than, yes, pollinator habitat could be lost."He notes President Clinton specifically mentioned pollinators, when he led the creation of the national monument in 1996."Bees need to be a part of the management decisions," Wilson says. "People should be aware of their pivotal role in our ecosystems."
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New Species
| 2,018 |
November 30, 2018
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https://www.sciencedaily.com/releases/2018/11/181130175058.htm
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New approach to assess sustainability of reef fish
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A new study helping to improve how sustainability is measured for popular reef fish could help better assess the eco-friendly seafood options at the dinner table.
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A team of researchers at the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science and NOAA Fisheries tested their newly developed fishery risk assessment method on groupers and snappers in the Florida Keys to determine if these tropical reef fish are being managed sustainability.The new approach developed by UM Rosenstiel School Professor Jerald Ault and colleagues uses fish size-structured abundance data to evaluate fisheries sustainability status, instead of the traditional "catch-per-unit effort" method that requires long-term information collected by fishers to assess the health of a fishery.The researchers then applied the length-based assessment to six key species in the Florida Keys region -- black grouper, red grouper, coney, mutton snapper, yellowtail snapper and hog snapper -- to evaluate the sustainability status of the fisheries.They found that only one species -- coney -- was within the sustainable range with a less than a 35 percent risk score. The other five species had estimated sustainability risks of greater than 95 percent.While the focus of this study was to develop a general length-based risk analysis methodology appropriate for data-limited fisheries worldwide, says the researchers, the results of the sustainability risk assessment for the species evaluated were in line with previous analyses for reef fishes in the Florida Keys and surrounding regions."The ecological and economic importance of tropical reef fish makes their sustainability a key conservation concern," said Ault, the lead author of the study. "The next challenge will be to evaluate the sustainability status of the over 50 principal exploited species in the Florida reef-fish community."The new risk analysis framework can evaluate the sustainability status of tropical reef fish stocks when traditional catch data are not reliable or available and provide a frame of reference to help balance sustainability risks with management decisions.In a separate but related study, Ault and colleagues developed a new fisheries-independent ecosystem monitoring survey to estimate biomass of deepwater snappers in the Hawaiian Islands. This new survey provides critical data for the risk analysis framework to assess fisheries sustainability in Hawaii."Our results help to improve the science and decision-making capacity for fisheries managers, and promotes the sustainability of coral reef fisheries subject to fishing and environmental changes," said Ault. "These combined methods will greatly improve the capacity and efficacy of fishery management for shallow and deep water coral reef fisheries in Florida, the U.S. Caribbean, and the U.S. Pacific Islands."The new methods developed are designed to ensure the quality of commercial and recreational fishing today and into the future, said Ault.
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New Species
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November 29, 2018
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https://www.sciencedaily.com/releases/2018/11/181129110141.htm
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Hidden biodiversity: 22 new moth species from across Europe
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Following a long-year study of the family of twirler moths, an Austrian-Danish research team discovered a startling total of 44 new species, including as many as 22 species inhabiting various regions throughout Europe.
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Given that the Old Continent is the most thoroughly researched one, their findings, published in the open access journal "The scale of newly discovered moths in one of the Earth's most studied regions is both sensational and completely unexpected," say authors Dr Peter Huemer, Tyrolean State Museum, and Ole Karsholt of the University of Copenhagen's Zoological Museum. To them, the new species come as proof that, "despite dramatic declines in many insect populations, our fundamental investigations into species diversity are still far from complete."For the authors, it all began when they spotted what seemed like an unclassifiable species of twirler moth in the South Tyrolean Alps. In order to confirm it as a new species, the team conducted a 5-year study into the type specimens of all related species spread across the museum collections of Paris, London, Budapest and many in between.To confirm the status of all new species, the scientists did not only look for characteristic colouration, markings and anatomical features, but also used the latest DNA methods to create unique genetic fingerprints for most of the species in the form of DNA barcodes.A particular challenge for the researchers was to choose as many as 44 names for the new species. Eventually, they named one of the species after the daughter of one of the authors, others -- after colleagues and many others -- after the regions associated with the particular species. Amongst the others, there is one which the scientists named All new moths belong to the genus of the large twirler moths (The genus of the large twirler moths presents an especially interesting group because of their relatively short wings, where their wingspan ranges between 8 and 26 millimetres and the females are often flightless. While it remains unknown why exactly their wings are so reduced, the scientists assume that it is most likely an adaptation to the turbulent winds at their high-elevation habitats, since the species prefer mountain areas at up to 3,000 metres above sea level.Out of the 85 documented species, however, both sexes are known in only 35 cases.The scientists suspect that many of the flightless females are hard to spot on the ground. Similarly, caterpillars of only three species have been observed to date.While one of the few things we currently know about the large twirler moths is that all species live on different grasses, Huemer and Karsholt believe that it is of urgent importance to conduct further research into the biology of these insects, in order to identify their conservation status and take adequate measures towards their preservation.
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New Species
| 2,018 |
November 28, 2018
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https://www.sciencedaily.com/releases/2018/11/181128082735.htm
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North American checklist identifies the fungus among us
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Some fungi are smelly and coated in mucus. Others have gills that glow in the dark. Some are delicious; others, poisonous. Some spur euphoria when ingested. Some produce antibiotics.
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All of these fungi -- and hundreds of thousands, if not millions, more -- occur in North America. Of those that are known to science, 44,488 appear in a new checklist of North American fungi, published this month in the journal "This checklist provides the basis for understanding our national mycoflora, which is timely since there is renewed interest in cataloging all North American fungi," said Illinois Natural History Survey mycologist Andrew Miller, who led the effort to compile the data. "Hundreds of citizen scientists are interested in helping with this project."By conservative estimates, scientists have so far documented less than one-third of all fungi thought to exist in North America, said Miller, who also is an affiliate of the department of plant biology at the University of Illinois at Urbana-Champaign, where the INHS is based.Collaborators on the checklist include Scott Bates, of Purdue University Northwest, and the Macrofungi and Microfungi Collections Consortia.While thousands of species of fungi were first identified and described from Europe, many North American fungi have evolved and diversified. Others are unique to the continent, Miller said."Many fungi in North America have European names, and while they may be related to their European counterparts, they often are genetically distinct," Miller said. "About half of the 44,488 fungi in the new checklist are type specimens, which means they are valid North American taxa."To compile the checklist, the team searched over 2.2 million records using the Mycology Collections Portal, which includes data from numerous universities, botanical gardens and other institutions. The researchers first built a checklist of all North American fungal species and subspecies, removed those categorized as lichen, then organized the list alphabetically by genus and species.About 20,000 of the fungi in the checklist are mushrooms; the rest are barely visible with the naked eye and are thus classified as "microfungi," Miller said. These include molds, mildews and rusts, along with species that break down organic matter in the soil.Some of the microfungi are pathogens, others are useful. The macrofungi can range in size from the barely visible to the colossal, Miller said."One of the largest living organisms on the planet is a honey mushroom, Another fungus, the giant puffball, "If every spore actually germinated and grew into a puffball, the puffballs produced would weigh more than the Earth," he said.Fungi have co-evolved with plants for millions of years and were instrumental in helping plants transition from aquatic environments onto land, Miller said. They are essential to the cycle of life, breaking down organic matter and converting it back to its fundamental components."Although an estimated 1.5-5.1 million species of fungi are believed to exist on Earth, only about 120,000 have been discovered and described," Miller said. "Obviously, we have a lot of work to do to fill in the gaps of our knowledge, but this checklist is a first step to getting our arms around North America's fungi."The INHS is a division of the Prairie Research Institute at the U. of I.This project was made possible by the National Science Foundation's Advancing Digitization of Biological Collections program, which supports the Macrofungi Collections Consortium and the Microfungi Collections Consortium.
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New Species
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November 27, 2018
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https://www.sciencedaily.com/releases/2018/11/181127092552.htm
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The warm and loving tegu lizard becomes a genetic resource
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Published today in the open-access journal
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Most reptiles are not able to control their body temperature like mammals do and instead must rely on its environment, such as available sun and shade, to attain an optimal body temperature. The tegu, The tegu genome sequence, provided by a team of researchers led by Michael Hiller at the Max Planck Institute for Molecular Cell Biology and Genetics in Dresden (Germany), is of unprecedented quality. To accomplish this the researchers used state-of-the-art technology to read the tegu's DNA and assemble its genome sequence. The newly released genome sequence of S. merianae is more than two billion DNA letters long and contains more than 22,000 genes. It is the most complete assembly of any reptile genome so far and will also aid scientists to study other lizards and snakes.By using so called "long read" (Pacific Biosciences) sequencing technology, the researchers were able to overcome some of the challenges of assembling reptile genomes. Hiller and first author Juliana Roscito explain: "Similar to other reptiles, a large portion of the tegu genomes consists of repetitive sequences, which occur many times in the genome. Repeats are a main problem when assembling a genome, especially when repeats are longer than the length of the sequenced DNA fragments, which results in gaps (breaks) in the assembly."The tegu is emerging as an interesting model species in its own right. One of the motivations for the authors to sequence the tegu genome actually related to their interest in another group of reptiles: snakes. The authors explain what they had in mind: "We were interested in studying limb loss in snakes and other reptiles. Since limbless reptiles had ancestors with fully developed limbs, we needed a well-assembled genome of a lizard with fully developed limbs as a reference." Given that there are few reptiles with sequenced genomes, the authors decided to produce this themselves.Another component of the article, especially given that reptiles are under-represented among. the vertebrates with sequenced genomes, the authors also provide a whole-genome alignment between the tegu and 16 other species. "We hope that these resources facilitate comparative reptile genomics to understand how unique morphological features evolved in this group of species and how vertebrate genomes evolve in general," Michael Hiller and Juliana Roscito conclude.
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New Species
| 2,018 |
November 27, 2018
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https://www.sciencedaily.com/releases/2018/11/181127092525.htm
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Newly discovered deep-sea microbes gobble greenhouse gases and perhaps oil spills, too
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Scientists at The University of Texas at Austin's Marine Science Institute have discovered nearly two dozen new types of microbes, many of which use hydrocarbons such as methane and butane as energy sources to survive and grow -- meaning the newly identified bacteria might be helping to limit the concentrations of greenhouse gases in the atmosphere and might one day be useful for cleaning up oil spills.
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In a paper published in "This shows the deep oceans contain expansive unexplored biodiversity, and microscopic organisms there are capable of degrading oil and other harmful chemicals," said assistant professor of marine science Brett Baker, the paper's primary investigator. "Beneath the ocean floor huge reservoirs of hydrocarbon gases -- including methane, propane, butane and others -- exist now, and these microbes prevent greenhouse gases from being released into the atmosphere."The new study, representing the largest-ever genomic sampling of Guaymas Basin sediments, was co-authored by former UT postdoctoral researcher Nina Dombrowski and University of North Carolina professor Andreas P. Teske.The researchers' analysis of sediment from 2,000 meters below the surface, where volcanic activity raises temperatures to around 200 degrees Celsius, recovered 551 genomes, 22 of which represented new entries in the tree of life. According to Baker, these new species were genetically different enough to represent new branches in the tree of life, and some were different enough to represent entirely new phyla."The tree of life is something that people have been trying to understand since Darwin came up with the concept over 150 years ago, and it's still this moving target at the moment," said Baker, who earlier was part of a team that mapped the most comprehensive genomic tree of life to date. "Trying to map the tree is really kind of crucial to understanding all aspects of biology. With DNA sequencing and the computer approaches that we use, we're getting closer, and things are expanding quickly."Only about 0.1 percent of the world's microbes can be cultured, which means there are thousands, maybe even millions, of microbes yet to be discovered.Baker's team investigates interactions between microbial communities and the nutrients available to them in the environment by taking samples of sediment and microbes in nature, and then extracting DNA from the samples. The researchers sequence the DNA to piece together individual genomes, the sets of genes in each organism, and infer from the data how microbes consume different nutrients."For this, we try to look for organisms that have been studied before and look for similarities and differences," said Dombrowski, who is now at the Royal Netherlands Institute for Sea Research. "This might initially sound easy, but really is not, since often more than half of the genes we find are so far uncharacterized and unknown."The samples were collected using the Alvin submersible, the same sub that found the Titanic, because the microbes live in extreme environments. Teske, who collaborated with Baker and Dombrowski, has driven sample collection at Guaymas Basin for several years, working with scientists across the world who are using different approaches to study life there.This month, Baker is part of a team on the Alvin sampling in areas of the basin that previously have never been studied."We think that this is probably just the tip of the iceberg in terms of diversity in the Guaymas Basin," Baker said. "So, we're doing a lot more DNA sequencing to try to get a handle on how much more there is. This paper is really just our first hint at what these things are and what they are doing."This research was supported by the U.S. Department of Energy, the Sloan Foundation and the U.S. National Science Foundation.
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New Species
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November 27, 2018
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https://www.sciencedaily.com/releases/2018/11/181127111055.htm
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A fresh look at winter footprints: Environmental DNA improves tracking of rare carnivores
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An innovative new project has discovered that animal footprints contain enough DNA to allow for species identification. Scientists have traditionally relied on snow-tracks and camera traps to monitor populations of rare carnivores, like Canada lynx, fishers and wolverines. These traditional techniques can tell part of, but not the entire story of an animal population, and are sometimes difficult to validate species identification.
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The study, led by the USDA Forest Service, collected snow samples within animal tracks from known locations of collared or photographed animals. DNA was extracted from these samples and analyzed with cutting-edge genomic tools and newly developed molecular genetic assays to identify each species. They found these assays positively detected the DNA of each species in various snow samples and outperformed traditional lab techniques on previously undetectable genetic samples, which suggests that this method could revolutionize winter surveys of rare species by greatly reducing or eliminating misidentifications and missed detections."It was the craziest thing, we were talking about how we use environmental DNA to detect aquatic species and thinking, maybe we could do the same in snow, since it is just water after all," said Thomas Franklin, a scientist with the USDA Forest Service National Genomics Center for Wildlife and Fish Conservation, who is lead author on the study. "This study shows that thinking outside the box and collaborating with researchers from other disciplines can pay real dividends in terms innovation and scientific advances."Monitoring for rare carnivores in the winter, using traditional methods, can be time intensive, expensive, and dangerous. "This new technique has the potential to make track misidentifications a thing of the past," said Jessie Golding, a study co-author and scientist with the USDA Forest Service. What this means for managers is gained efficiency and accuracy, and that better information will be available to help conserve these species of concern.
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New Species
| 2,018 |
November 26, 2018
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https://www.sciencedaily.com/releases/2018/11/181126142853.htm
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'Old-fashioned fieldwork' puts new frog species on the map
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Months of old-fashioned scientific fieldwork -- more than 2,000 surveys of chirping frog calls, hundreds of photos of individual frogs and tiny tissue samples taken from them -- has helped define the range and unique characteristics of the recently discovered Atlantic Coast leopard frog.
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A study published this month in the journal Given the challenges associated with hearing one frog and then finding and processing it in an expansive wetland, the researchers essentially triangulated their way to the information they were seeking. "Hearing a particular frog call, then going out, finding and catching it is pretty much an impossible task," Schlesinger said. "It doesn't happen that way." So, based on call surveys, they documented which frog species lived in which wetlands, then caught individual frogs from those wetlands for genetic and photographic analysis.The call surveys were conducted from Massachusetts to North Carolina. A team of 19 scientists and a cadre of field assistants ventured into wetlands up and down the East Coast in 2014 and '15 to listen for and record the "chuck" sound that sets the Atlantic Coast leopard frog apart from other species of leopard frogs. When possible, the scientists captured a frog, photographed it from multiple angles and clipped a tissue sample from its toes. The tissue underwent genetic analysis at UCLA."It's very old-fashioned field work," Schlesinger said. "You go out and do survey work and catch some animals. You look at their characteristics. And then you bring in some modern technology."The work resulted in the first field-verified range map for the species, which lives primarily in coastal plains from Connecticut to northern North Carolina.Schlesinger and colleagues first described the Atlantic Coast leopard frog as a distinct species in a study in
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New Species
| 2,018 |
November 23, 2018
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https://www.sciencedaily.com/releases/2018/11/181123134400.htm
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Gigantic mammal 'cousin' discovered
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During the Triassic period (252-201 million years ago) mammal-like reptiles called therapsids co-existed with ancestors to dinosaurs, crocodiles, mammals, pterosaurs, turtles, frogs, and lizards. One group of therapsids are the dicynodonts. Researchers at Uppsala University in Sweden, together with colleagues in Poland, have discovered fossils from a new genus of gigantic dicynodont. The new species Lisowicia bojani is described in the journal
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The earth is about 4.5 billion years old and has gone through many geological periods and dramatic change. During the Triassic period, about 252-201 million years ago, all land on Earth came together and formed the massive continent called Pangea. During this time, the first dinosaurs came into being as well as ancestors to crocodiles, mammals, pterosaurs, turtles, frogs, and lizards. Recently, scientists have become interested in another type of animal, therapsids. Therapsids were "mammal-like" reptiles and are ancestors to the mammals, including humans, found today. One group of therapsids is called dicynodonts. All species of dicynodonts were herbivores (plant eaters) and their sizes ranged from small burrowers to large browsers. Most of them were also toothless. They survived the Permian mass extinction and became the dominant terrestrial herbivores in the Middle and Late Triassic. They were thought to have died out before the dinosaurs became the dominant form of tetrapod on land.For the first time, researchers in the research programme Evolution and Development at Uppsala University in collaboration with researchers at the Polish Academy of Sciences (Warsaw), have discovered fossils from a new species of dicynodont in the Polish village of Lisowice. The species was named Lisowicia bojani after the village and a German comparative anatomist named Ludwig Heinrich Bojanus who worked in Vilnius and is known for making several important anatomical discoveries. The findings show that the Lisowicia was about the size of a modern-day elephant, about 4.5 metres long, 2.6 metres high and weighed approximately 9 tons, which is 40 percent larger than any previously identified dicynodont. Analysis of the limb bones showed that they had a fast growth, much like a mammal or a dinosaur. It lived during the Late Triassic, about 210-205 million years ago, about 10 million years later than previous findings of dicynodonts."The discovery of Lisowicia changes our ideas about the latest history of dicynodonts, mammal Triassic relatives. It also raises far more questions about what really make them and dinosaurs so large," says Dr Tomasz Sulej, Polish Academy of Sciences."Dicynodonts were amazingly successful animals in the Middle and Late Triassic. Lisowicia is the youngest dicynodont and the largest non-dinosaurian terrestrial tetrapod from the Triassic. It's natural to want to know how dicynodonts became so large. Lisowicia is hugely exciting because it blows holes in many of our classic ideas of Triassic 'mammal-like reptiles'," says Dr Grzegorz Niedzwiedzki, Uppsala University.The first findings of fossils from Lisowice in Poland were made in 2005 by Robert Borz?cki and Piotr Menducki. Since then, more than 1,000 bones and bone fragments have been collected from the area, including fossils from Lisowicia. The area is thought to have been a river deposit during the Late Triassic period.The discovery of Lisowicia provides the first evidence that mammal-like elephant sized dicynodonts were present at the same time as the more well-known long-necked sauropodomorph dinosaurs, contrary to previous belief. Sauropodomorphs include species like the Diplodocus or Brachiosaurus. It fills a gap in the fossil record of dicynodonts and it shows that some anatomical features of limbs thought to characterize large mammals or dinosaurs evolved also in the non-mammalian synapsid. Finally, these findings from Poland are the first substantial finds of dicynodonts from the Late Triassic in Europe."The discovery of such an important new species is a once in a lifetime discovery," says Dr Tomasz Sulej.
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New Species
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November 20, 2018
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https://www.sciencedaily.com/releases/2018/11/181120125903.htm
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Sticky and heavily armed, a tomato-relative is the new 'star' of the Brazilian inselbergs
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Armed with long thorns and sticky stems, newly described plant
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Recently described in open access journal In fact, the new species is baptised after yet another showy defence mechanism. The name kollastrum comes from the Greek words for glue and star, referring to the peculiar sticky hairs that end in a star-like formation.While all this heavy armour might at first fool you that this new species lives in isolation, a closer look has revealed that, contrary to the expectations, Field observations of the new species have suggested that it's preferred by medium- to large-sized bees with buzzing behaviour. The fruit structure of The heavy armour is, in fact, not that unusual in the group of 'spiny solanums' to which the new species belongs. With approximately 110 species of spiny solanums, the Brazilian In its own right, Endemic to eastern Brazil, the known records of the armed new species are mostly concentrated along the Mucuri River watershed, where it inhabits edge of small forest fragments. In fact, the species is especially seen in areas at the base or on the peculiar and gigantic geological formations known as inselbergs or 'sugar loaves'). Some populations were also found in disturbed sites near these rock outcrops, such as borders of unpaved roads and pastures."The discovery of "This highlights how urgent the need is to describe, study and conserve the country's plant diversity. Thus, we hope that this discovery encourages the study on the most diverse aspects of this species' biology."
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New Species
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November 15, 2018
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https://www.sciencedaily.com/releases/2018/11/181115145107.htm
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Human activity may influence the distribution and transmission of Bartonella bacteria
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<em>Bartonella</em>
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Cross-species The authors note that "phylogenetic inferences about the origin of infections should be interpreted with caution as they are heavily influenced by available data and the taxa that have been sampled." More data are needed to verify findings and fill in remaining knowledge gaps. However, their study advances scientific understanding of human impacts on the spread of infectious disease: "In thinking about disease transmission between animals and humans, we often focus on the animals as the source of new human infections and not the role of the humans in influencing their own risk. Our findings suggest that humans play a significant role in changing infection patterns not only for ourselves but for our domestic animals and wildlife, too."
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New Species
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November 14, 2018
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https://www.sciencedaily.com/releases/2018/11/181114104045.htm
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Advanced computer technology and software turn species identification interactive
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Representing a group of successful biocontrol agents for various pest fruit flies, a parasitic wasp genus remains largely overlooked. While its most recent identification key dates back to 1969, many new species have been added since then. As if to make matters worse, this group of visually identical species most likely contains many species yet to be described as new to science.
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Having recently studied a species group of these wasps in Central Europe, scientists Fabian Klimmek and Hannes Baur of the Natural History Museum Bern, Switzerland, not only demonstrate the need for a knowledge update, but also showcase the advantages of modern taxonomic software able to analyse large amounts of descriptive and quantitative data.Published in the open access The fully illustrated interactive database covers 27 species in the group and 18 related species, in addition to a complete diagnosis, a large set of body measurements and a total of 585 images, displaying most of the characteristic features for each species."Nowadays, advanced computer technology, measurement procedures and equipment allow more sophisticated ways to include quantitative characters, which greatly enhance the delimitation of cryptic species," explain the scientists."Recently developed software for the creation of biological identification keys like Xper3, Lucid or Delta could have the potential to replace traditional paper-based keys."To put the statement into context, the authors give an example with one of the studied wasp species, whose identification would take 16 steps if the previously available identification key were used, whereas only 6 steps were needed with the interactive alternative.One of the reasons tools like Xper3 are so fast and efficient is that the key's author can list all descriptive characters in a specific order and give them different weight in species delimitation. Thus, whenever an entomologist tries to identify a wasp specimen, the software will first run a check against the descriptors at the top, so that it can exclude non-matching taxons and provide a list of the remaining names. Whenever multiple names remain, a check further down the list is performed, until there is a single one left, which ought to be the one corresponding to the specimen. At any point, the researcher can access the chronology, in order to check for any potential mismatches without interrupting the process.Being the product of digitally available software, interactive identification keys are not only easy, quick and inexpensive to publish, but they are also simple to edit and build on in a collaborative manner. Experts from all around the world could update the key, as long as the author grants them specific user rights. However, regardless of how many times the database is updated, a permanent URL link will continue to provide access to the latest version at all times.To future-proof their key and its underlying data, the scientists have deposited all raw data files, R-scripts, photographs, files listing and prepared specimens at the research data Zenodo, created by OpenAIRE and CERN.
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New Species
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November 13, 2018
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https://www.sciencedaily.com/releases/2018/11/181113115438.htm
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'Rare' jellyfish not so rare
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When the
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In 1827 the French naturalists Jean René Constant Quoy and Joseph Paul Gaimard, while aboard the Astrolabe on a trip around the worlkd, discovered a new jellyfish species in the Strait of Gibraltar. Describing the During the following decades, this jellyfish went unnoticed and there were no scientific records of it over the last 60 years. It was not until 2013 when a team of scientists, led by Laura Prieto of the Institute of Marine Sciences of Andalusia (CSIC), confirmed the presence of this species in Mediterranean waters by means of a phylogenetic analysis."We believe that every time it was seen, it was mistakenly identified with such other jellyfish as the The new work, part of the future doctoral thesis by Karen Kienberger and recently published in the The results confirm more than 150 observations in the last 17 years, "which shows that it is not such a rare species after all," the authors emphasize."With this work, we did research work to see if what we thought was an unusual species was really one that had been ill-identified for many years," explains Prieto. The R. luteum is frequent in the coastal waters of the west and south coasts of the Iberian peninsula and the west and north coasts of Africa.The jellyfish can reach a diameter of more than 60 cm with some specimens; the oral arms end differently and sometimes -- but not always -- they are very long, and can reach more than two metres."Its geographical distribution is very wide: from Portugal to South Africa in the Atlantic and in the Alboran Sea in the Mediterranean. With subsequent studies, we've been able to verify that the mother carries her protected offspring in her gonads until she releases them in an appropriate environment," the researcher reports.In order to detect the jellyfish, Laura Prieto and Karen Kienberger were helped by citizens who sent historical accounts, photographs and videos taken in the North-East Atlantic Ocean and the Alboran Sea. "Posters were distributed in diving and marine clubs and a lot of non-scientific outreach literature, such as books on diving or marine fauna, was subjected to revision," says Prieto.The scientists contacted many authors of the photos, and explored open social networks and open access databases on jellyfish that included photos. "Any citizen could (and can) send an email with the place, the date and the photo of a sighting," the authors stress.For the researchers, this type of work makes it possible to monitor biodiversity and the manner in which species respond to climate change in marine ecosystems.
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New Species
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November 13, 2018
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https://www.sciencedaily.com/releases/2018/11/181113080917.htm
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The first cave-dwelling centipede from southern China
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Chinese scientists recorded the first cave-dwelling centipede known so far from southern China. To the amazement of the team, the specimens collected during a survey in the Gaofeng village, Guizhou Province, did not only represent a species that had been successfully hiding away from biologists in the subterranean darkness, but it also turned out to be the very first amongst the order of stone centipedes to be discovered underground in the country.
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Found by the team of Qing Li, Xuan Guo and Dr Hui-ming Chen of the Guizhou Institute of Biology, and Su-jian Pei and Dr Hui-qin Ma of Hengshui University, the new cavedweller is described under the name of Australobius tracheoperspicuus in the open-access journal The new centipede is quite tiny, measuring less than 20 mm in total body length. It is also characterised with pale yellow-brownish colour and antennae composed of 26 segments each. Similar to other cave-dwelling organisms which have evolved to survive away from sunlight, it has no eyes.In their paper, the authors point out that Chinese centipedes and millipedes remain poorly known, where the statement holds particularly true for the fauna of stone centipedes: the members of the order Lithobiomorpha. As of today, there are only 80 species and subspecies of lithobiomorphs known from the country. However, none of them lives underground.In addition, the study provides an identification key for all six species of the genus Australobius recorded in China.
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New Species
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November 12, 2018
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https://www.sciencedaily.com/releases/2018/11/181112095942.htm
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New light cast on fishing throughout history
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A new study from The Australian National University (ANU) has revealed new insights into ancient fishing throughout history, including what type of fish people were regularly eating as part of their diet.
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The study looked at fish bones unearthed in an archaeological dig on the Indonesian island of Alor -- home to the world's oldest fish-hooks ever found in a human burial site, dating back to about 12,000 years.Lead archaeologist Dr Sofia Samper Carro of the ANU School of Archaeology and Anthropology said on the study identified a shift in fishing behaviours about 7,000 years ago."People on Alor people were fishing for open water species about 20,000 years ago, then about 7,000 years ago they started to fish exclusively for reef dwelling species," she said.Dr Samper Carro said a similar pattern was identified on the nearby island of Timor, indicating that the change in behaviour was due to environmental circumstances."It seems to be due to changes in sea levels and environmental conditions, although human-induced changes cannot be ruled out," she said.The results were made possible through the use of an analysis method traditionally used in biology to identify fish habitat in archaeological material. Dr Samper Carro said she was forced to experiment with a new approach due to the difficulty in determining the difference between the very similar looking bones of the area's 2,000 known species of fish."This study is the first time researchers have been able to reliably determine fish habitat using vertebra through this method, and represents a significant step forward in being able to track human behaviour throughout history," Dr Samper Carro said."Most of the bones you find in archaeological sites are vertebra, which are very complicated to identify to species and all look very similar."If we don't know the species, we don't know their habitat."In Indonesia you have more than 2,000 species of fish, so to be able to know which bones belong to which species you would need 2,000 species of fish in your comparative collection."I spent probably five months trying to match each fish vertebra to a species and I think I got through 100 out of 9,000 bones, so I needed to find another method."Dr Samper Carro instead turned to geometric morphometrics, a process that looks at slight differences in size and shape of physical objects. Using more than 20,000 digital images and plotting 31 points on each bone, she was able to digitally identify the likely habitat from each vertebra.
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New Species
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November 9, 2018
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https://www.sciencedaily.com/releases/2018/11/181109101419.htm
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Sequencing pollen DNA to discover insect migratory routes
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Metabarcoding, a technique of mass DNA sequencing, allows for tracing migratory routes of insects, an understudied subject due to technical limitations. A small DNA fragment of the pollen that insects transport is used as a barcode to identify the plant species they visited previously.
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This British Ecological Society-funded study shows that transcontinental pollination mediated by migrating insects is possible and, therefore, various plants located very far apart can mix.The migration of insects is a natural phenomenon as important as it is unknown. In fact, it has only been studied in depth in some emblematic species, such as the migratory locust and the monarch butterfly. The reasons, in short, are the technical limitations to study this behaviour.Now, in a study published in the journal By means of this technique, a small DNA fragment can identify the plant species to which the pollen belongs to, analogously to a barcode. By knowing the geographic distribution of the plant species detected, we can infer the place where the insect was feeding and, therefore, its migratory route.Previously, long-distance migrations were studied either by capture-mark-recapture experiments, or through telemetry using radio trackers. These two methods, however, have great disadvantages: the recapture rate of marked individuals is extremely low; as for telemetry, it is only feasible to track the largest insects over short distances, given the weight of the transmitters and their short battery life.Another method to study long-distance migrations involves analysing hydrogen or carbon isotopes present in organic tissues, because they provide information about where the insects were born. However, the resolution of isotope analyses is low and this method is only useful for insects that migrate on very large distances.When insects feed on the flowers, pollen is deposited on their bodies and can be transported over long distances. Taxonomical classification of the pollen grains using optical and electron microscopy, however, is often impossible at species level. In addition, it requires a great investment of time and having specialized knowledge in taxonomy, which is why this is an unsuitable tool for large-scale studies.However, as explained by Roger Vila, one of the authors of the study and principal investigator at IBE, "the development of next-generation sequencing technologies has made it possible to massively sequence the genetic material present in a sample of pollen from various individuals."This is the metabarcoding technique, in which the species are identified from a small region of the DNA that performs a function analogous to that of a barcode.The researchers used the metabarcoding technique to study the pollen from 47 specimens of migrating painted lady butterflies (Vanessa cardui), which have been captured on the Spanish Mediterranean coast during spring. The objective was to test if the sequences obtained were from endemic African plant species and to shed light on the migratory circuits of these butterflies.The analysis revealed pollen of 157 species of plants of 23 different orders; the vast majority were, indeed, African and not present in Europe.The painted lady has recently been shown to be the butterfly species that performs the longest migrations in the world, traveling every year between tropical Africa and Europe (back and forth, crossing the Sahara desert) in successive generations, although the precise routes are still unknown.The results of this study represent an important discovery from the point of view of the plants, because it demonstrates, for the first time that the transcontinental pollination by migratory insects is possible. It is a phenomenon to be taken into account both in wild and in cultivated plants because it enables plants from very distant locations to mix."We hope that the technique opens a new line of research that helps to clarify which insects migrate, which routes they follow and when, as we still do not know much about the impact of insect migration for ecosystems and the transmission of diseases," says Gerard Talavera, co-author of the article, researcher at IBE and National Geographic Explorer.The project was funded by the National Geographic Society, the British Ecological Society, the European Community and the Spanish Ministerio de Ciencia, Innovación y Universidades.
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New Species
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November 8, 2018
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https://www.sciencedaily.com/releases/2018/11/181108130514.htm
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The secret behind coral reef diversity? Time, lots of time
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Strap on a diving mask and fins and slip under the crystal-clear water near a coral reef in Indonesia, Papua-New Guinea or the Philippines, and you'll immediately see why divers and snorkelers from across the world flock to the area. Known as the Coral Triangle, the region is famous for its unmatched diversity of reef fish and other marine creatures.
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Fish of all shapes and colors dart in and out of crevices created by the dazzling shapes of corals, colorful sponges and other reef-building organisms. With a little luck, a diver might catch a glimpse of a shark patrolling the reef or a turtle soaring across the landscape of colors.While underwater enthusiasts have long known and cherished the biodiversity in the Central-Indo Pacific Ocean, scientists have struggled for more than half a century to explain what exactly makes the region the world's No. 1 hot spot of marine biodiversity and sets it apart from other marine regions around the world.Several hypotheses have been put forth to explain the Central-Indo Pacific region's extraordinary diversity. Some researchers suggested species emerge at a faster rate there compared to other parts of the world's oceans, while others attributed it to the region's central location between several species-rich swaths of ocean in the broader Indo-West Pacific. Still others pointed to the region's low extinction rates.Now, a study led by University of Arizona doctoral student Elizabeth Miller has revealed that Indo-Pacific coral reefs have accumulated their unrivaled richness of fish species not because of some unknown, elusive quality, but simply because they had the time."People used to think that new species evolve more quickly in tropical marine areas, so you get the high diversity we see today very quickly," Miller said. "Instead, we found that diversity in the Central-Indo Pacific has slowly built over a long time."The study, published in the journal Until now, Miller explained, it was widely believed that tropical coral reefs, similar to tropical rain forests, are hot spots of biodiversity because of an intrinsic propensity to diversify into more species than other regions. Her research showed that wasn't the case.The team discovered that speciation rates are actually higher in cold marine areas such as the Arctic and Antarctic. However, while changes in biodiversity in the Central-Indo Pacific region could be compared to a slow but long-burning flame, in colder ocean regions, they are more like fireworks."There, species evolve relatively quickly, but each glaciation period clears out much of what was there before," Miller said. "Once the glaciers recede, they leave empty niches waiting to be repopulated by new species."Frequent environmental upheaval results in overall biodiversity being lower in colder ocean regions.In the Coral Triangle, on the other hand, new species have evolved less rapidly, but because conditions have been much more stable over long periods of geological time, they were more likely to stick around once they appeared and slowly accumulate to the biological diversity we see today."This suggests that a region may need long-term stability to accumulate high species diversity," Miller said. "According to our study, the magic number appears to be 30 million years."In the Central-Indo Pacific, plate tectonics created a wide platform of shallow ocean, while its central location made it a target for colonization. It was the right place at the right time for the fishes that colonized the region."Things haven't changed much there in the past 30 to 35 million years," Miller said. "In contrast, other marine regions, such as the Caribbean, underwent periods of instability and isolation, and therefore fewer colonizations and higher rates extinction of the lineages that were there previously -- all those factors add up to less evolutionary time."For the study, Miller and her team used distribution data of almost all spiny ray-finned fishes -- 17,453 species in total, representing about 72 percent of all marine fishes and about 33 percent of all freshwater fishes. They used several different statistical methods to reconstruct the causes of underlying species richness patterns among global marine regions.To disentangle how marine fish diversity unfolded over time, the team then used a published evolutionary tree of this fish group and performed biogeographic reconstructions."Biogeographic reconstructions help us understand where ancestors were living at various places back in time, based on where species live today and how they are related," Miller said. "It's easy if you only compare two species that live in the same place, but if you have thousands of species and go back further and further in time, more ancestors come into play and things become more difficult."Evolutionary biologists rely on sophisticated computer algorithms to manage and interpret the extremely large data sets. The method used by Miller and her team created many hypothetical scenarios of where species evolved. The researchers then used these scenarios to test how different models explain today's biodiversity."It's like drawing family histories, each slightly different," Miller said. "You start out with analyses and repeat them hundreds of times, each time based on some possible history to try and encompass uncertainty to see how they play out. In our study, it turned out the uncertainty is low, which is reassuring. It means it's a really robust result."The general idea that patterns of diversity can be explained by how long a group has been present rather than how quickly they proliferate is relevant to lots of different systems, according to the researchers. For example, biologists have observed that the timing of colonization explains the high diversity of certain animal groups in terrestrial ecosystems, such as treefrogs in the Amazon rainforests, salamanders in the Appalachian Mountains and lizards in the desert Southwest."The general takeaway is that these patterns of high diversity may take tens of millions of years to arise, but can be wiped out in a few years by human impacts," said John Wiens, senior author of the paper and a professor in the UA Department of Ecology and Evolutionary Biology. "Unfortunately, the high diversity of reef fish in the Coral Triangle may soon disappear because of the impacts of human-induced climate change on coral reefs. The diversity that gets lost in the next few years may take tens of millions of years to get back."
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New Species
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November 8, 2018
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https://www.sciencedaily.com/releases/2018/11/181108110040.htm
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Species' longevity depends on brain cell numbers
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Scientists have thought that the main determinant of maximal longevity in warm-blooded animals -- which varies from as little as 2 to as many as 211 years -- is a species' metabolic rate, which is inversely related to body size. It follows that at 2 years of life, small animals with high metabolic rates are already old, but large animals with low metabolic rates are still young.
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New research published in The Specifically, it appears that the more cortical neurons a species has, the longer it takes to mature, and the longer it lives thereafter. This may relate to the importance of the cortex not only for cognitive capabilities, but also for adaptability of physiological functions related to heart rate, respiratory rate, and metabolism."These new findings imply that everybody's brains accumulate damages at a similar rate, and the longer the brain still has enough neurons that are sufficiently healthy to keep the body functioning as a well-integrated whole, the longer one lives," said author Dr. Suzana Herculano-Houzel, of Vanderbilt University. "This puts the brain squarely in the center of new initiatives to promote healthy aging and wellbeing throughout the lifespan."
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November 7, 2018
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https://www.sciencedaily.com/releases/2018/11/181107082457.htm
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Utah's Grand Staircase-Escalante National Monument home to rich bee diversity
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The state of Utah's nickname is "The Beehive State," and the moniker couldn't be more apt, say Utah State University scientists. One out of every four bee species in the United States is found In Utah and the arid, western state is home to more bee species than most states in the nation. About half of those species dwell within the original boundaries of the newly reduced Grand Staircase-Escalante National Monument.
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"The monument is a hotspot of bee diversity," says USU-Tooele entomologist Joseph Wilson, associate professor in USU's Department of Biology, who, with scientist and USU alum Olivia Messinger Carril, USDA entomologist Terry Griswold and USU emeritus professor James Haefner, reported 660 species now identified in the protected region in the November 7, 2018 issue of Carril is lead author of the paper, which describes a four-year study, funded by the U.S. Bureau of Land Management and the USDA, in southern Utah's GSENM. "We identified almost as many species as are known in the entire eastern United States," says Carril, a bee researcher based in Santa Fe, NM. "We discovered 49 previously unknown species, as well as 150 'morphospecies,' that is, somewhat unique species that don't match known species."Located in south central Utah, about 250 miles south of Salt Lake City and 200 miles northeast of Las Vegas, Grand Staircase is situated in the arid, sandstone Kaiparowits Plateau and adjacent canyons."Many are surprised to learn 87 percent of Utah's flowering plant species live within the monuments boundaries," Carril says. "Which likely contributes to the rich diversity of pollinators."Bees found within the monument's original boundaries, she says, include ground-nesters, cavity and twig-nesters, cleptoparasites, narrow specialists, generalists, solitary and social species. During the team's study, the bee fauna reached peak diversity each spring, but also experienced a second peak in diversity in late summer, following monsoonal rains. "It's an amazing natural laboratory of pollinators, of which we don't know a lot," Wilson says. "The large reduction of this protected areas could have implications for future biodiversity."
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November 6, 2018
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https://www.sciencedaily.com/releases/2018/11/181106111603.htm
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Tropical mountain species in the crosshairs of climate change
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Lack of varied seasons and temperatures in tropical mountains have led to species that are highly adapted to their narrow niches, creating the right conditions for new species to arise in these areas, according to a new study published in the
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Still, the same traits that make tropical mountains among the most biodiverse ecosystems on Earth also make the species that live there more vulnerable to rapid climate changes, the study finds.The research compares rates of species evolution in three types of aquatic stream insects -- mayflies (Ephemeroptera), stoneflies (Plecoptera) and caddisflies (Trichoptera) -- in temperate and tropical mountain areas. The findings have implications for similar patterns in other tropical mountain species.An interdisciplinary team of physiologists, geneticists and genomics specialists, population biologists and taxonomists from four universities gathered samples and data from mountain streams in the Colorado Rocky Mountains and in the Ecuadorian Andes over a two-year period."Because the tropics are not as seasonal as the more northern temperate zones, bugs in the tropics can't get too cold or too hot, and thus they have a narrow thermal breadth," said Kelly Zamudio, professor in the Department of Ecology and Evolutionary Biology at Cornell University, and a senior co-author of the study. "We also found that they move less up and down the side of the mountain, and there are more species [on tropical mountains] as a result. Nobody had tested all three of those patterns in the same system before."The findings support and reveal the mechanisms behind a classic 1967 paper that predicted these dynamics.Factors of temperature tolerance and range of movement also effect how species in each of these regions will respond to climate change. Because tropical species can't withstand large temperature shifts and have limited movement, they are much more susceptible to rapid temperature shifts due to anthropogenic climate change."It's really paradoxical that the same factors that lead to a lot of species are the factors that are going to endanger those species in the tropics," Zamudio said.
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November 6, 2018
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https://www.sciencedaily.com/releases/2018/11/181106104255.htm
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Tiny thorn snail discovered in Panama's backyard
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Discoveries of biodiversity at the Lilliputian scale are more tedious than it is for larger animals like elephants, for example. Furthermore, an analysis producing a DNA barcode -- a taxonomic method using a short snippet of an organism's DNA -- is not enough to adequately identify it to the species level.
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In the case of tiny thorn snails -- appearing as minute white flecks grazing in moist, decomposing leaf litter -- it is the shell that provides additional and reliable information needed to verify or question molecular assessment of these otherwise, nondescript critters.However, at 2 mm, thorn snails are too small and fragile to handle and the few, if any, tangible details on the outside of the shells can only be seen using a high-powered microscope and computed tomographic (CT) images.This is exactly how the interdisciplinary team of Dr Adrienne Jochum, Naturhistorisches Museum der Burgergemeinde Bern (NMBE) and University of Bern, Dr. Bernhard Ruthensteiner, Zoologische Staatssammlung Muenchen, Germany, Dr. Marian Kampschulte, University Hospital of Giessen and Marburg, Gunhild Martels, Justus-Liebig University Giessen, Jeannette Kneubühler, NMBE and University of Bern, and Dr. Adrien Favre, Senckenberg Research Institute and Natural History Museum Frankfurt, managed to clarify the identity of a new Panamanian species. Their study is published in the open-access journal Even though the molecular analysis flagged what it was later to be named as the new to science species, The new snail is currently the second member of the family Carychiidae to be discovered in Panama. The first Panamanian, and southern-most member of its kind in the Western Hemisphere, is C. zarzaae, which was also described by Dr. A. Jochum and her team along with two sister species from North and Central America. The study was published in Much like X-rays showing the degree of damage in a broken bone, CT images visualise the degree of sinuosity of the potato chip-like wedge (lamella) along the spindle-like mast (columella) inside the thorn snail's shell. These structures provide stability and surface area on which the snail exerts muscular traction while manoeuvring the unwieldy and pointed, signature thorn-like shell into tight nooks and crannies. The alignment and degree of waviness of the lamella on the columella is also used by malacologists (mollusc specialists) to differentiate the species.Normally, a study of a thorn snail's shell would require drilling out minute 'windows' in the shell by using a fine needle under a high microscope magnification."This miserable method requires much patience and dexterity and all too often, the shell springs open into oblivion or disintegrates into dust under pressure," explains Dr. A. Jochum. "By exposing the delicate lamella using non-manipulative CT imaging, valuable shell material is conserved and unknown diversity in thorn snails becomes widely accessible for further study and subsequent conservation measures."The authors are hopeful that C. panamaense and C. zarzaae, which both inhabit the La Amistad International Park, Chiriquí, will remain a conservation priority along with other animalian treasures including the Resplendent Quetzal, Three-Wattled Bellbird and the Crested Eagles.The park is considered the 1st bi-national biosphere reserve, as it occupies land in both Costa Rica and Panama, and constitutes a UNESCO World Heritage Site since 1990.
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November 1, 2018
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https://www.sciencedaily.com/releases/2018/11/181101085237.htm
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Origin of an isolated bird species on South Atlantic island
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By wings or maybe riding on debris, that's how a now-flightless and rare species of tiny birds likely got to Inaccessible Island, an aptly named small island of volcanic origin in the middle of the South Atlantic.
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And it turns out that the bird, a rail, listed scientifically as Inaccessible Island, the westernmost of three islands in the Tristan Archipelago, is the only place in the world where this species of rail lives. The island, formed by a now-extinct volcano 3 to 6 million years ago, is located roughly 3,600 kilometers (2,250 miles) east of Porto Alegre, Brazil, and about 2,800 kilometers (1,750 miles) west of Cape Town, South Africa.The birds were first described in 1923 by British surgeon Percy Lowe, a bird-lover who then headed the ornithology collections at the British Museum. He placed the birds in the genus Atlantisia, a reference to mythical Atlantis, and named the species rogersi after the Rev. H.M.C. Rogers, a chaplain on nearby island Tristan da Cunha, who was the first to collect specimens.Lowe surmised that the birds walked to the island on a since-sunken land bridge from Africa or South America, but the later discovery of plate tectonics ruled out that idea, Stervander said."We found obviously that the birds did not walk by foot," he said. "They flew or were assisted by floating debris. Whether they flew all the way or were swept off by a storm and then landed on debris, we can't say. In any case, they managed to make it from the mainland of South America to Inaccessible Island."Using modern sequencing of mitochondrial and nuclear DNA and phylogenetic methods, Stervander's team tied the island's rail to the South American dot-winged crake, a rail species known as Porzana spiloptera. The split came 1.5 million years ago, with the rail colonizing Inaccessible Island in a single migration, the team concluded in a paper put online Oct. 12 by the journal Their genetics also make them relatives of black rails (Stervander's team recommends that the Inaccessible Island rail species be reclassified in the genus Laterallus as are the related species."We are sorry to be suggesting that we take away this beautiful name, Atlantisia, which is something we can all love, but we can now say that the closest relatives of this species are American birds that were given their name before the Inaccessible Island rail," Stervander said.When the birds arrived at the island, they found three predator-free habitats -- grasslands, tree fern bogs and woodland -- and abundant food sources, including worms, moths, berries and seeds. Soon after, the reclusive birds no longer needed strong wings for survival and evolved into a flightless species, he said.Stervander visited the island once, traveling by ship and helicopter in 2011, while a doctoral student at Sweden's Lund University. His research built on earlier efforts by study co-author Peter G. Ryan of the University of Cape Town.The genetic analyses began while Stervander was at Lund University and was completed using computational resources at the UO, where Stervander is doing research under a three-year fellowship from the Swedish Research Council.The island's rail population, Stervander said, is in a delicate situation. While some 5,500 mature birds now thrive on the island, an accidental introduction of rats or other predators could destroy them. Fossils found on other islands suggest that numerous other flightless rail species had been there but fell to predation with the arrival of humans.The rail is classified as vulnerable on the International Union for Conservation of Nature's red list of species threatened with extinction.The paper's other two co-authors are Martim Melo of the University of Cape Town and the CIBIO Research Centre in Biodiversity and Genetic Resources in Portugal, and Bengt Hansson of Lund University.The South African National Antarctic Programme, Swedish Research Council and Portuguese Science Foundation supported the research.
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New Species
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October 31, 2018
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https://www.sciencedaily.com/releases/2018/10/181031141426.htm
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Ballistic beetles seek safety in numbers by sheltering with other species
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A group of ground beetles known as bombardier beetles are famous for shooting a boiling-hot, noxious liquid at would-be attackers, but despite their formidable defense, they prefer not to shelter alone, according to a study publishing October 31 in the open-access journal
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Bombardier beetles in the genus Brachinus are nocturnal predators that shelter during the day in dark, moist crevices on the banks of rivers, but their tendency to form large groups containing many similar species has puzzled scientists because they would be expected to compete over food and territory. To investigate, the researchers sequenced DNA from all bombardier beetles in 59 sheltering groups collected in the Sonoran Desert Region in Arizona, conducting the first ever phylogenetic analysis for such a multi-species grouping.They found that groups included up to eight bombardier species -- 71% of groups contained at least two species and 21% provided a home to three or more species. The beetles tended to group with distantly related species on the Brachinus tree, which mate at different times of year -- a strategy that may help the beetles avoid accidental hybridization, the authors suggest. The team also video-recorded beetles in the lab as they chose from a selection of artificial shelters and found that individuals preferred to join existing groups rather than shelter alone, but most showed no preference for exactly which species they sheltered with.Bombardier beetles probably benefit from safety in numbers by sheltering with other beetles that share their lethal chemical defense strategy. It takes around 24 hours to recharge their noxious chemicals after use, but resting with other bombardiers may help ensure that more ammunition is available instantly to fend off persistent predators.Moore adds: "To me, the most important aspect of this study is that it combines fieldwork, natural history observations, behavioral ecology, and molecular phylogenetics to drill down on a question."
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New Species
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