Creatures adapt to changing environments ... the fact that at the end of the Permian Period they were gone seems unthinkable.

Some have proposed that the disappearance of certain predators and competitors allowed some of the surviving creatures to thrive. And others have proposed that the climate changes associated with the ...

Toward the end of the Permian period, Earth was reeling from ... where the die-offs of certain predator and competitor creatures allow one surviving group of organisms to go gangbusters.

About 250 million years ago, at the end of the Permian period, something killed some 90 percent of the planet's species. Less than 5 percent of the animal species in the seas survived. On land ...

proposed multiple mechanisms for why different locations had remarkably similar inhabitants following the end-Permian extinction. One hypothesis is "ecological release," where the die-offs of certain ...

These toughened-up creatures represented a crucial innovation ... the world's oceans until they were wiped out in the Permian extinctions about 250 million years ago. Photograph by James L.