Template:PD Help Page

The big mass extinction took place in chicxulub crater were the asteroid hit and were the dinosaurs Died on the impact. So today, a Stegosaurus fossil is found in western North America since 155 MYA.

Notes: Stegosaurus means amored dinosaur or protected dinosaur. See in Wikipedia for completion datas About stegosaurus. Lived in the late jurrasic and Early cretecious period (155 MYA- 145 MYA).