Why the Shells You Find on the Beach Survived Earth’s Worst Extinction

Why the shells you find on the beach survived Earth’s worst extinction

Scientists have found why some sea creatures survived Earth’s biggest extinction while others disappeared, showing that rising temperatures and falling oxygen levels played a major role, with warnings for today.Samples of the modern fauna (left three samples) and the Paleozoic fauna (right four samples). Credit: Sarah Leibovitz.A new study led by Stanford University describes how some marine life survived the planet’s largest mass extinction. Ar…

The worst mass extinction in Earth's history struck 252 million years ago, before dinosaurs had even appeared: eruptions in what is now Siberia produced millions of cubic kilometres of basalt—enough, at the highest estimates, to bury the continental United States nearly a kilometre deep—and wiped out as many as 90 percent of marine species.

The asteroid that ended the age of dinosaurs is the extinction most people can name. It left a crater, a global layer of debris and an unforgettable victim in Tyrannosaurus rex. It was not the worst mass extinction in Earth’s history. That distinction belongs to the end of the Permian Period, about 252 million years ago. The crisis arrived before dinosaurs existed and struck a world filled with entirely different communities. In the sea, the lat…