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Categories: Paleontology: Early Mammals and Birds, Physics: Acoustics and Ultrasound

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Aiming to emulate the quantum characteristics of materials more realistically, researchers have figured out a way to create a lattice of light and atoms that can vibrate -- bringing sound to an otherwise silent experiment.

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The flying reptiles known as pterosaurs are the closest relatives of dinosaurs and were the first vertebrates to evolve powered flight. However, many details of pterosaur flight anatomy and performance are still unclear. According to a new study pterosaurs evolved a muscular wing-body junction to reduce drag and improve flight performance.

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New examinations of skeletons and animal embryos have allowed researchers to discover how mammals developed protruding, flexible noses. This study contributes to uncovering the origin of mammals' strong sense of smell and creates the potential for new animal models, like chickens or frogs, that are often used in lab experiments to investigate facial development disorders such as cleft palate.

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Investigators have developed and tested a targeted contrast agent that can detect blood clots in the hearts of patients with atrial fibrillation, or an irregular heartbeat. The strategy could be used to find clots in other parts of the body as well, such as in vessels that, when blocked, can lead to stroke.

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Some people are born with hearing loss, while others acquire it with age, infections or long-term noise exposures. In many instances, the tiny hairs in the inner ear's cochlea that allow the brain to recognize electrical pulses as sound are damaged. As a step toward an advanced artificial cochlea, researchers report a conductive membrane, which translated sound waves into matching electrical signals when implanted inside a model ear, without requiring external power.

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Researchers trace the first tusks back to ancient mammal relatives that lived before the dinosaurs and shed light on the evolution of mammalian tusks by first defining what makes a tusk a tusk.

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Humans did not cause woolly mammoths to go extinct -- climate change did. For five million years, woolly mammoths roamed the earth until they vanished for good nearly 4,000 years ago -- and scientists have finally proved why. The hairy cousins of today's elephants lived alongside early humans and were a regular staple of their diet -- their skeletons were used to build shelters, harpoons were carved from their giant tusks, artwork featuring them is daubed on cave walls, and 30,000 years ago, the oldest known musical instrument, a flute, was made out of a mammoth bone.

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Researchers found that complex teeth, a hallmark of mammals, also evolved several times in reptiles, prompting the evolutionary success of plant-eating lizards. However, contrary to mammals their tooth evolution was not unidirectional.

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Although there has been evidence of our species living in rainforest regions in Southeast Asia from at least 70,000 years ago, the poor preservation of organic material in these regions limits how much we know about their diet and ecological adaptations to these habitats. An international team of scientists has now applied a new method to investigate the diet of fossil humans: the analysis of stable zinc isotopes from tooth enamel. This method proves particularly helpful to learn whether prehistoric humans and animals were primarily eating meat or plants.

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When an asteroid struck 66 million years ago and wiped out dinosaurs not related to birds and three-quarters of life on Earth, early ancestors of primates and marsupials were among the only tree-dwelling (arboreal) mammals that survived, according to a new study.

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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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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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Physics researchers discover a new physical effect relating to the interactions between light and twisted materials -- an effect that is likely to have implications for emerging new nanotechnologies in communications, nanorobotics and ultra-thin optical components.

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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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Researchers have studied aerosol production from playing wind instruments, singing and acting, allowing them to develop recommendations to minimize COVID transmission.

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Researchers outline an algorithm that adapts personalized sound zones within a car to changes in seat position, allowing riders to listen to their own audio without headphones and interruption.

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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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Researchers have devised an ingenious method of using acoustics to conceal and simulate objects.