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Categories: Biology: Evolutionary, Paleontology: Early Mammals and Birds

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Researchers describe five new deep-sea squat lobster species. Combining molecular data and microCT their findings show a wider species distribution range and shallower genetic diversity, calling for a revision of the current classification of squat lobsters.

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90% of the plants and animals on Madagascar are found nowhere else on Earth, but this treasure trove of evolution is under serious threat due to habitat loss, over-hunting, and climate change. In this study, researchers examined how long it took Madagascar's unique modern mammal species to emerge and estimated how long it would take for a similarly complex set of new mammal species to evolve in their place if the endangered ones went extinct: 23 million years, far longer than scientists have found for any other island.

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All chlamydiae today live inside the cells of hosts ranging from amoeba to animals. A team of scientists found that the ancestor of chlamydiae likely already lived inside host cells, but that chlamydiae infecting amoeba evolved later in ways unexpected for intracellular bacteria. The study is an important step for understanding the emergence and evolution of endosymbiotic bacteria, including human pathogens.

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Lizards living in different cities have parallel genomic markers when compared to neighboring forest lizards, according to a new study. The genetic variations linked to urbanization underlie physical differences in the urban lizards, including longer limbs and larger toe pads that show how these lizards have evolved to adapt to city environments.

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Smallpox was once one of humanity's most devastating diseases, but its origin is shrouded in mystery. For years, scientific estimates of when the smallpox virus first emerged have been at odds with historical records. Now, a new study reveals that the virus dates back 2,000 years further than scientists have previously shown, verifying historical sources and confirming for the first time that the disease has plagued human societies since ancient times.

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What genetic changes are responsible for the evolution of phenotypic traits? This question is not always easy to answer. A newly developed method now makes the search much easier.

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Orangutans, mice, and horses are covered with it, but humans aren't. Why we have significantly less body hair than most other mammals has long remained a mystery. But a first-of-its-kind comparison of genetic codes from 62 animals is beginning to tell the story of how people -- and other mammals -- lost their locks.

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Microraptor was an opportunistic predator, feeding on fish, birds, lizards -- and now small mammals. The discovery of a rare fossil reveals the creature was a generalist carnivore in the ancient ecosystem of dinosaurs.

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Sediment cores obtained from Eifel maar sites provide insight into the presence of large Ice Age mammals in Central Europe over the past 60,000 years: Overkill hypothesis not confirmed. Herds of megafauna, such as mammoth and bison, have roamed the prehistoric plains in what is today's Central Europe for several tens of thousands of years. As woodland expanded at the end of the last Ice Age, the numbers of these animals declined and by roughly 11,000 years ago, they had completely vanished from this region. Thus, the growth of forests was the main factor that determined the extinction of such megafauna in Central Europe.

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While the Diprotodon -- the extinct megafauna species that is distantly related to wombats but was the size of a small car -- is commonly (but incorrectly) thought of as Australia's 'giant wombat', researchers have shed light on a large species that does belong in the modern-day wombat family. The complete skull of this true fossil giant wombat, found in a Rockhampton cave in Queensland, Australia and estimated to be around 80,000 years old, has been described for the first time.

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Researchers have tested the biting efficiency of Smilodon, an extinct species of carnivore close to the extant felines. Using high-precision 3D scans and simulation methods, the team has just revealed how these animals managed to bite despite the impressive length of their teeth.

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Dinosaurs dominated the world right up until a deadly asteroid hit the earth, leading to their mass extinction, some 66 million years ago, a landmark study reveals. Fresh insights into dinosaurs' ecosystems -- the habitats and food types that supported their lives -- suggests that their environments were robust and thriving, right up until that fateful day, at the end of the Cretaceous period.

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Fossilized fragments of a skeleton, hidden within a rock the size of a grapefruit, have helped upend one of the longest-standing assumptions about the origins of modern birds.

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Paleontologists say environmental DNA is not always helpful in identifying when animals like mammoths went extinct because genetic material found in sediment could have come from animals that died thousands of years earlier.

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A new study compiles data on more than 3,000 species to show how climate and geologic changes across Asia over the last 66 million years have shaped the evolution of the continent's mammals.

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A new study finds that bird species with extreme or uncommon combinations of traits face the highest risk of extinction.

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For a species of flycatcher in the remote Solomon Islands, scientists have so far found at least two genetic pathways leading to the same physical outcome: all-black feathers. This change was no random accident. It was a result of nature specifically selecting for this trait.

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Piecing together the crushed skull of a fossil bird that lived alongside the dinosaurs helped researchers extrapolate what its brain would have looked like: big olfactory bulbs would have meant that this bird, the earliest known animal to eat fruit, had a better sense of smell than most modern birds. And the bones around its eye sockets revealed that it would have been better at seeing by day than at night.

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Today, increasing levels of carbon dioxide in the atmosphere are warming up the planet. Climate change can disrupt the balance of ecosystems and contribute to endangerment and extinction of some species. New research suggests that a period of intense volcanism in the Central Andes may be the missing link in the story of past climate changes that led to the extinctions of ancient marine mammals.

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A giant kangaroo that once roamed on four legs through remote forests in the Papua New Guinea Highlands may have survived as recently as 20,000 years ago -- long after large-bodied megafauna on mainland Australia went extinct, new research indicates. Palaeontologists, archaeologists and geoscientists, have used new techniques to re-examine megafauna bones from the rich Nombe Rock Shelter fossil site in Chimbu Province in a bid to better understand the intriguing natural history of PNG.