Exactly where and when dinosaurs first evolved are still open questions in paleontology; it’s hard to even say what the first dinosaur was. In this episode, we dig into the evidence for dinosaur origins in the Triassic Period (between 252 and 201 million years ago) and try to understand the world they lived in. Being able to point to the first dinosaur might tell us something about how the biggest mass extinction of all time influenced the course of life on our planet. Eons: Mysteries of Deep Time is produced by Complexly for PBS. © 2022 PBS. All rights reserved.