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Categories: Mathematics: Statistics, Paleontology: Early Mammals and Birds

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The ancestors of modern mammals managed to evolve into one of the most successful animal lineages -- the key was to start out small and simple, a new study reveals.

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A team of researchers compared the genomes of woolly mammoths with modern day elephants to find out what made woolly mammoths unique, both as individuals and as a species. The investigators report that many of the woolly mammoth's trademark features -- including their woolly coats and large fat deposits -- were already genetically encoded in the earliest woolly mammoths, but these and other traits became more defined over the species' 700,000+ year existence. They also identified a gene with several mutations that may have been responsible for the woolly mammoth's miniscule ears.

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An international research team has determined that Troodon, a dinosaur very close to modern birds, was a warm-blooded animal (an endotherm), but had a reproductive system similar to that of modern reptiles. The scientists applied a new method which allowed for accurate determination of the temperature when the egg's carbonate shell was formed. Furthermore, the researchers showed that Troodon laid 4 to 6 eggs per clutch. As nests with up to 24 Troodon eggs had been found, the scientists conclude that several Troodon females laid their eggs in communal nests.

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A new study suggests that predatory dinosaurs, such as Tyrannosaurus rex, did not have permanently exposed teeth as depicted in films such as Jurassic Park, but instead had scaly, lizard-like lips covering and sealing their mouths.

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A new study investigates how an extinct, carnivorous marsupial relative with canines so large they extended across the top of its skull could hunt effectively despite having wide-set eyes, like a cow or a horse. The skulls of carnivores typically have forward-facing eye sockets, or orbits, which helps enable stereoscopic (3D) vision, a useful adaptation for judging the position of prey before pouncing. Scientists studied whether the 'marsupial sabertooth' Thylacosmilus atrox could see in 3D at all.

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Researchers have mapped the sparse life hidden away in salt domes, rocks and crystals at Salar de Pajonales at the boundary of the Chilean Atacama Desert and Altiplano. Then they trained a machine learning model to recognize the patterns and rules associated with their distributions so it could learn to predict and find those same distributions in data on which it was not trained. In this case, by combining statistical ecology with AI/ML, the scientists could locate and detect biosignatures up to 87.5 percent of the time and decrease the area needed for search by up to 97 percent.

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A review of evidence from prior research provides new support for the possibility that the evolution of larger brains in some species was enabled through increased energy investment by parents in their offspring.

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Researchers have created and preliminarily tested what they believe may be one of the first models for predicting who has the highest probability of being resistant to COVID-19 in spite of exposure to SARS-CoV-2, the virus that causes it.

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Scientists have compared the relationship among the strength of flight bones, body mass, and the way modern birds fly to better understand the evolution of flight in birds and extinct animals, such as the Pteranodon.

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Researchers tested a large sample of the major AI technologies available today and found that not only did they reproduce human biases in facial age recognition, but they exaggerated those biases.

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Synthetic populations are computer-generated models that mimic real-world populations in terms of characteristics such as age, gender, and occupation; they are useful when conducting social simulations. In a recent study, researchers developed a new approach to assign workplaces to individuals in a synthetic Japanese population with household information, based on ODI (Origin-Destination-Industry) data. Their efforts will enable more accurate, realistic simulations of the day-time distribution of workers in Japan, helping to improve decision-making and planning.

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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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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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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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A new paper presents a mathematical model for the motion of bacteria that includes cell division and death, the basic ingredients of the cell cycle.

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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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A new study shows machine-learning models trained using simple symptoms, demographic features are effective in predicting COVID-19 infections.

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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.