What did the remains of dinosaurs found in the Western Unite...

What did the remains of dinosaurs found in the Western United States tell us?

Hi guest
You might want to be a little more specific. Dinosaur fossils from the Western USA span ~150 million years (I assume that New Mexico and Wyoming counts as Western), covering all 3 mesozoic time periods. That's a long time.

..but in general they tell us that most of the Western USA was above sea level during the mesozoic. Much of Europe was submerged under water in the time of the dinosaurs and the Central USA was a shallow inland-sea during the Cretaceus.