In a new paper in Science, experts from the University of Chicago describe steps that took place some 66 million years ago to ...

It was about the size of a dog — it walked on two legs, ate plants and had spiky armored plates on its back — kind of like its distant family member the stegosaurus. Good morning. I'm Leila Fadel.

A species of dinosaur recently discovered in Argentina had an armored back, distinctive jaw and tiny arms — and was roughly the size of a dog. Fossils dated to the humid Late Cretaceous period — ...