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Nov 26, 2008 | 10
Ever wonder how a turtle got its shell? You're not the only one. Evolutionary biologists and paleontologists have long been stumped by the question. But a recently unearthed turtle fossil, the oldest on record, may hold the answer. Researchers report in Nature today that the fossil indicates shells evolved as an extension of turtles' backbones and ribs.
"Its discovery opens a new chapter in the study of the origins and early history of these fascinating reptiles," says vertebrate paleontologists Robert Reisz and Jason Head of the University of Toronto, in a commentary accompanying the article.
Scientist have been in the dark until now because all fossilized turtles previously discovered had complete shells. But this 220 million-year-old fossil is an ancestor of the modern turtle at a stage when its shell was still evolving.
Nov 24, 2008 | 34
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Increased carbon dioxide (CO2) in the atmosphere is making the Pacific coast acidic far more rapidly than previously believed, potentially wreaking havoc for creatures living in it that are unable to tolerate the swiftly changing environment.
Ecologists at the University of Chicago tracked the acidity of the Pacific off an island close to Washington state over the course of eight years. Their results, published today in Proceedings of the National Academy of Sciences: the waters here are becoming acidic 10 times more quickly than had been predicted using other models. Their data also shows that populations of mussels—key animals in that ecosystem—are declining rapidly as the ocean becomes less alkaline.
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The Geoffrey Beene Foundation Alzheimer’s Initiative (GBFAI) is launching the 2013 Geoffrey Beene Global NeuroDiscovery Challenge whose
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