Fossil tracks from 545 million years ago suggest complex life forms were already crawling around before the Cambrian ...

A newly documented fossil site in Morocco’s Western Anti-Atlas reveals rare evidence of the Ediacaran-Cambrian transition, a ...

At least five times, a catastrophe has killed off the vast majority of Earth’s species. As scientists say we’re in a sixth mass extinction, what can we learn from the past?

Editor's Note: This story was updated on Friday, Dec. 22 at 4:15 p.m. E.D.T. to correct the timing of the first mass extinction. It occurred 20 million, not 20, years after the Cambrian explosion.