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Categories: Biology: Evolutionary, Paleontology: Dinosaurs

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Scientists have deciphered a comprehensive, continuous genome for a parasite responsible for transmitting Lyme disease and other serious infections to hundreds of thousands of Americans yearly. With their newly described genome for the black-legged tick, or deer tick, the researchers identified thousands of novel genes and new protein functions, including proteins associated with tick immunity, disease transmission and developmental stages.

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The discovery of more than 250 fossilized eggs reveals intimate details about the lives of titanosaurs in the Indian subcontinent, according to a new study.

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Madagascar is home to a unique biodiversity with a large number of endemic species, among those many lemur species, including the mouse lemurs. This diversity is also found in their retroviruses. Biologists analyzed the mouse lemur genome and identified viruses of two classes that represent ancient infections of the mouse lemur germline. The viruses now behave similarly to lemur genes and are thus called endogenous retroviruses (ERVs). It was surprising that some of the identified retroviruses are closely related to viruses found in other, very different mammals such as polar bears or domestic sheep. This suggests an intriguing and complex pattern of host switching of retroviruses, much more complex than previously thought.

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A study is providing a glimpse into dinosaur and bird diversity in Patagonia during the Late Cretaceous, just before the non-avian dinosaurs went extinct. The fossils represent the first record of theropods -- a dinosaur group that includes both modern birds and their closest non-avian dinosaur relatives -- from the Chilean portion of Patagonia. The researchers' finds include giant megaraptors with large sickle-like claws and birds similar to todays ducks and geese.

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The crocodilian edition of hemoglobins -- the scuba tanks of the blood -- work so well that crocs can go hours without air. The hyper-efficiency of that adaptation has led some biologists to wonder why, of all the jawed vertebrates, crocodilians were the lone group to hit on such an optimal solution to making the most of a breath. After resurrecting the hemoglobin of ancient crocodilian ancestors, a team may have an answer.

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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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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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Europasaurus is a long-necked, herbivorous dinosaur that lived in the Late Jurassic, about 154 million years ago, on a small island in modern-day Germany. Recently, scientists examined fossil braincase material of Europasaurus with the aid of micro-computed tomography (micro-CT). The digital reconstruction of the inner ear of Europasaurus gave the researchers new insights not only into its hearing ability, but also into its reproductive and social behavior.

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The earliest dinosaurs included carnivorous, omnivorous and herbivorous species, according to a team of palaeobiologists.

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Climate change, rather than competition, played a key role in the ascendancy of dinosaurs through the Late Triassic and Early Jurassic periods.

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Scratches on dinosaur teeth could reveal what they really ate. Dental microwear texture analysis (DMTA) has now been used to infer the feeding habits of large theropods, including Allosaurus and T. rex. By taking 3D images of individual teeth and analyzing the pattern of marks scratched into them, researchers could reason which dinosaurs may have frequently crunched on hard bone and which may have regularly eaten softer foods and prey. This technique opens up a new avenue of research for paleontology, helping us to better understand not only dinosaurs themselves but also the environment and communities in which they lived.

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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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Scientists have found new evidence for how armored dinosaurs used their iconic tail clubs. The exceptional fossil of the ankylosaur Zuul crurivastator has spikes along its flanks that were broken and re-healed while the dinosaur was alive -- injuries that the scientists think were caused from a strike by another Zuul's massive tail club. This suggests ankylosaurs had complex behavior, possibly battling for social and territorial dominance or even engaging in a 'rutting' season for mates.

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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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The oldest Pterodactylus specimen was found near Painten, Germany. The fossil is about one million years older than other Pterodactylus specimens. The specimen is a complete, well-preserved skeleton of a small-sized individual. With a 5-cm-long skull, it represents a rare 'sub-adult' individual.