The discovery of Ahvaytum bahndooiveche, a 230-million-year-old dinosaur in Wyoming, reveals dinosaurs existed in the northern hemisphere earlier than believed, challenging past theories. When and how did dinosaurs first appear and spread across the planet over 200 million years ago?

Paleontologists released a new report last week showing that the earliest dinosaur ever discovered in North America is from Wyoming. It's a

With a recent radioisotopic analysis of the fossil specimens dating the remains to around 230 million years old, this tiny 'terrible lizard' named Ahvaytum bahndooiveche is now the oldest-known dinosaur from Laurasia, the Northern Hemisphere land mass of the late Paleozoic supercontinent Pangea.

Researchers discovered Ahvaytum bahndooiveche fossils in Wyoming, revealing dinosaurs in Laurasia earlier than believed.