Backed by a National Science Foundation grant of more than $500,000, Pfeifer, the lead principal investigator, and a team of ...
The Earth has experienced five major mass extinctions, beginning with the Ordovician period about 443 million years ago, and continuing through the Devonian, Permian, Triassic, and Cretaceous periods ...
Sharks might be the all time bullet-dodging champions. They’ve been around for about 450 million years, longer than trees, longer than the rings of Saturn, and longer than most of the other life on ...
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