A weathered sign in the Minnesota River Valley proudly proclaims: “World’s Oldest Rock.” Erected in 1975, it marks a 3.8-billion-year-old gneiss — or so scientists thought.

Researchers created 3D models of ancient tracks in Oregon’s John Day Fossil Beds National Monument. The study revealed a ...

They’re like terrifying versions of crabs, with a sort of gravitational attraction to the same body form again and again.

Ancient giant crocodiles that rivaled dinosaurs once thrived in North America. A new study led by Hungarian researchers ...