mass extinction
Scientific-
The extinction of a large number of species within a relatively short period of geological time, thought to be due to factors such as a catastrophic global event or widespread environmental change that occurs too rapidly for most species to adapt. At least five mass extinctions have been identified in the fossil record, coming at or toward the end of the Ordovician, Devonian, Permian, Triassic, and Cretaceous Periods. The Permian extinction, which took place 245 million years ago, is the largest known mass extinction in the Earth's history, resulting in the extinction of an estimated 90 percent of marine species. In the Cretaceous extinction, 65 million years ago, an estimated 75 percent of species, including the dinosaurs, became extinct, possibly as the result of an asteroid colliding with the Earth.
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The most famous mass extinction included the destruction of the dinosaurs sixty-five million years ago. (See Alvarez hypothesis.)
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"This lets us more precisely infer causality between events in the geologic record, for example a meteor impact structure and a mass extinction," Renne said.
From Science Daily ● Sep. 30, 2026
It was in this ancient world, shortly after the greatest mass extinction in Earth’s history that a new species of fossil reptile discovered in the interior of Brazil’s Rio Grande do Sul state.
From Science Daily ● Aug. 10, 2026
Scientists agree that we're living though the world's sixth mass extinction event, the first caused by humans.
From BBC ● Aug. 8, 2026
They were more resistant to drying out, which would have been crucial in the dry and unstable climate following the mass extinction.
From Science Daily ● Apr. 14, 2026
Researchers had previously noted the temporal coincidence between the paleo-Indians’ arrival and the mass extinction, but they didn’t believe that small bands of hunters could wreak such ecological havoc.
From "1491" by Charles C. Mann
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