Learn about the time period that took place 251 to 199 million ... including rodent-size mammals and the first dinosaurs. By the start of the Triassic, all the Earth's landmasses had coalesced ...

Explore the age of the dinosaurs. Discover what the prehistoric world was like and how it changed between when dinosaurs first appeared and the mass extinction at the end of the Cretaceous Period. Non ...

The Triassic period stands out in Earth’s history as the time when dinosaurs first evolved. It was followed by the Jurassic and Cretaceous periods – at the end of the latter, the dinosaurs ...