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Categories: Biology: Developmental, Paleontology: General

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Humans began altering environments long before records were kept of the things that lived in them, making it difficult for scientists to determine what healthy ecosystems should look like. Researchers show the recent fossil record preserves a reliable snapshot of marine environments as they existed before humans.

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Movement in the Earth's tectonic plates indirectly triggers bursts of biodiversity in 36 million-year cycles by forcing sea levels to rise and fall, new research has shown.

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Research shows global cooling of the climate 10 million years ago led to an explosion of diversity in terrestrial orchids.

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Extinct dwarf hippos that once roamed Madagascar lived in forests rather than open grasslands preferred by common hippos on mainland Africa. The findings suggest grasslands that now cover much of the enormous island off the eastern coast of southern Africa were a relatively recent change facilitated by people rather than a natural habitat sustained in part by these famously large vegetarians.

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Researchers describe a 500 million-year-old tunicate fossil species. The study suggests that the modern tunicate body plan was already established soon after the Cambrian Explosion.

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Birds are the only group of dinosaurs that survived the asteroid-induced mass extinction 66 million years ago. But not all the birds alive at the time made it. Why the ancestors of modern birds lived while so many of their relatives died has been a mystery that paleontologists have been trying to solve for decades. Two new studies point to one possible factor: the differences between how modern birds and their ancient cousins molt their feathers.

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Biomechanical studies on the arachnid-like front 'legs' of an extinct apex predator show that the 2-foot (60-centimeter) marine animal Anomalocaris canadensis was likely much weaker than once assumed. One of the largest animals to live during the Cambrian, it was probably agile and fast, darting after soft prey in the open water rather than pursuing hard-shelled creatures on the ocean floor.

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An international team has, for the first time, accurately determined the age of the East Anatolian fault, allowing geologists to learn more about its seismic history and tendency to produce earthquakes.

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The lower jaws of lizards, birds, fish and even dinosaurs are comprised of multiple bones per side. Yet mammals diverged from all other vertebrates and settled on just one bone, repurposing the extra bones into a more elaborate inner ear, perhaps the better to hear. The single bone per side, fused in primates into one jawbone, makes the jaw more rigid. A paleontologist asks, Did the stiffer, rigid jaw make mammals more successful?

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Scientists have filled a major gap in the state's fossil record -- describing the first known Jurassic vertebrate fossils in Texas. The weathered bone fragments are from the limbs and backbone of a plesiosaur, an extinct marine reptile.

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Scientists have been mystified as to why animals are missing in much of the fossil record. Researchers have now developed a new method to determine if animals really were absent during certain geological eras, or if they were present but too fragile to be preserved.

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A Cretaceous origin for placental mammals, the group that includes humans, dogs and bats, has been revealed by in-depth analysis of the fossil record, showing they co-existed with dinosaurs for a short time before the dinosaurs went extinct.

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50 million years ago in what is now northwestern Colorado, a katydid died, sank to the bottom of a lake and was quickly buried in fine sediments, where it remained until its compressed fossil was recovered in recent years. When researchers examined the fossil under a microscope, they saw that not only had many of the insect's hard structures been preserved in the compressed shale, so had several internal organs and tissues, which are not normally fossilized.

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How the megalodon, a shark that went extinct 3.6 million years ago, stayed warm was a matter of speculation among scientists. Using an analysis of tooth fossils from the megalodon and other sharks of the same period, a study suggests the animal was able to maintain a body temperature well above the temperature of the water in which it lived. The finding could help explain why the megalodon went extinct during the Pliocene Epoch.

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Researchers have identified the oldest decisive evidence of humans' close evolutionary relatives butchering and likely eating one another.

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Warmer temperatures are known to make more turtle eggs become female hatchlings, but new research shows that those females also have a higher capacity for egg production, even before their sex is set. This finding may explain why many animals besides turtles have temperature-dependent sex determination and why the system persists, despite seeming like a risky strategy. It may also provide a troubling glimpse of what could lie ahead in a warming world.

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An obscure aquatic plant has helped to explain how plants avoid cracking up under the stresses and strains of growth.

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Engineers designed a technology to probe connections between the brain and the digestive tract. Using fibers embedded with a variety of sensors, as well as optogenetic stimulation, the researchers could control neural circuits connecting the gut and the brain, in mice.

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Fifteen years of archaeological work in the Tam Pa Ling cave in northeastern Laos has yielded a reliable chronology of early human occupation of the site. The team's excavations through the layers of sediments and bones that gradually washed into the cave and were left untouched for tens of thousands of years reveals that humans lived in the area for at least 70,000 years -- and likely even longer.

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Researchers have outlined the structure and function of a protein complex which is required to repair damaged DNA and protect against cancer.