Behind the dinosaurs was a case with skulls of Permian synapsids. They don't get many visitors. Lystrosaurus, the synapsid that inherited the barren world of the Triassic, stared out empty-eyed.

Dinosaurs evolved from more primitive reptiles in the aftermath of Earth's biggest mass-extinction event caused by extreme ...

They were the only group of dinosaurs to survive the Cretaceous mass extinction around 65 million years ago (not to be confused with the Permian-Triassic mass extinction that happened some 250 million ...

This also marked the first time the earliest dinosaurs appeared. The Permian period’s mass extinction had wiped out the mammals that could have been competitors for these reptiles on land and in ...

One member of this group was a large, sail-backed animal called dimetrodon, which looks like it could be a dinosaur but isn’t. Then 252 million years ago came the Permian-Triassic extinction event.