A 29- to 28-million-year-old primate fossil found in Saudi Arabia assists scientists in timing a major evolutionary transition.

A recently discovered fossil demonstrates that giant whales weren’t always as gentle as they are today.

Warm-bloodedness may help explain the creatures’ evolutionary success, a new study suggests.

After examining more than 90 new specimens of Nectocaris pteryx, paleontologists put it near the root of the cephalopod evolutionary tree.