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

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Two thirds of all mammals vanished from Africa and the Arabian Peninsula around 30 million years ago, when the climate on Earth changed from swampy to icy. But we are only finding out about this mass extinction now. Researchers examined hundreds of fossils from multiple sites in Africa, built evolutionary trees, and pinpointed each species' first and last known appearances. The climate shift 'was a real reset button.'

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Scientists are using a new mathematical tool to predict how combinations of genetic mutations cause different types of tumors.

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The first 3D reconstructions of extinct Cretaceous birds reveal a reptilian tooth replacement pattern.

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As early as 18,000 years ago, humans in New Guinea may have collected cassowary eggs near maturity and then raised the birds to adulthood, according to an international team of scientists, who used eggshells to determine the developmental stage of the ancient embryos/chicks when the eggs cracked.

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Mathematical modeling of disease spread suggests that herd immunity could be achieved with fewer vaccine doses by using Bluetooth-based contact-tracing apps to identify people who have more exposure to others -- and targeting them for vaccination.

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When researchers first started to look at animal bones from Contrebandiers Cave, Morocco, they wanted to learn about the diet and environment of early human ancestors who lived there between 120,000 and 90,000 years ago. But they soon realized that the bones they had found weren't just meal scraps. They'd been shaped into tools, apparently for use in working leather and fur.

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Peacock tails are just one example of how evolution walks a line between favoring traits that make it easier to survive, and traits that make it easier to find a mate. In a new study, scientists have found evidence of this age-old conundrum in the form of a fossil bird from the Early Cretaceous with a pair of elaborate tail feathers longer than its body.

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Archaeologists have long had a dating problem. The radiocarbon analysis typically used to reconstruct past human demographic changes relies on a method easily skewed by radiocarbon calibration curves and measurement uncertainty. And there's never been a statistical fix that works -- until now.

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A new study has discovered the oldest known cavities found in a mammal, the likely result of a diet that included eating fruit.

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The conditions under which early members of the genus Homo dispersed outside Africa were analysed on a broader scale, across Europe during the Early and Middle Pleistocene. The model is based on the comparison of functional trait distribution of large herbivorous mammals in sites with archaeological or fossil evidence of human presence and in sites, which lack evidence of human presence.

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Bird dispersal movements are thought to depend on complex demographic and genetic factors. Researchers show that there may be a simpler explanation: bird dispersal distances depend on the morphology and flight efficiency of the wings. Bird populations and the capacity of species to move across the landscape can determine which species will thrive and which may become endangered.

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The rise and fall of Earth's land surface over the last three million years shaped the evolution of birds and mammals, a new study has found, with new species evolving at higher rates where the land has risen most.

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The COVID-19 pandemic may be the deadliest viral outbreak the world has seen in more than a century. But statistically, such extreme events aren't as rare as we may think, asserts a new analysis of novel disease outbreaks over the past 400 years. A newly assembled record of past outbreaks was used to estimate the probability of a pandemic with similar impact to COVID-19 is about 2 percent in any year. And that probability is growing.

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Scientists have discovered three new species of ancient creatures from the dawn of modern mammals that hint at rapid evolution immediately after the mass extinction of the dinosaurs.

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A new study has revealed that over the last 20,000 to 50,000 years, birds have undergone a major extinction event, inflicted chiefly by humans, which caused the disappearance of about 10 to 20 percent of all avian species. According to the researchers, the vast majority of the extinct species shared several features: they were large, they lived on islands, and many of them were flightless.

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Research on a newly discovered bird fossil found that a unique brain shape may be why the ancestors of living birds survived the mass extinction that claimed all other known dinosaurs.

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Newly-hatched pterosaurs may have been able to fly but their flying abilities may have been different from adult pterosaurs, according to a new study. Researchers found that hatchling humerus bones were stronger than those of many adult pterosaurs, indicating that they would have been strong enough for flight.

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A new method could lead to more accurate predictions of how new materials behave at the atomic scale.

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Researchers have modeled COVID-19 completion versus cessation in clinical trials using machine learning algorithms and ensemble learning.

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A major challenge in cancer therapy is the adaptive response of cancer cells to targeted therapies. Although this adaptive response is theoretically reversible, such a reversal is hampered by numerous molecular mechanisms that allow the cancer cells to adapt to the treatment. A team has used information theory, in order to objectify in vivo the molecular regulations at play in the mechanisms of the adaptive response and their modulation by a therapeutic combination.