More than two decades after scientists identified a fossil as the world’s oldest octopus — officials now say it wasn’t one at ...

Modern Nautilus and Allonautilus species inhabit deeper waters than their extinct ancestors did over 500 million years ago.

Skeleton season may be just around the corner, but the skeleton age dawned with the early Cambrian Period, about 538 million to 506 million years ago. Subscribe to our newsletter for the latest ...

For years, this fossil seemed to tell a thrilling story. Here was an animal from more than 300 million years ago that ...

The species in question was a therapsid, a group of animals that was the forefather to modern-day mammals, including humans.