Paleontologists say the fossils could prove dinosaurs lived in the northern hemisphere millions of years earlier than previously thought.

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?

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

This small, chicken-sized dinosaur lived around 230 million years ago. Interestingly, this pushes back the timeline for dinosaur presence in the northern hemisphere by millions of

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.

A newfound "chicken-size" dinosaur, recently unearthed in Wyoming, changes what paleontologists thought they knew about how dinosaurs spread across the globe.