The dinosaurs dominated the Earth for over 165 million years during the Mesozoic Era, but mysteriously went extinct 65 million years ago. Paleontologists study their fossil remains to learn about the amazing prehistoric world of dinosaurs.

When the dinosaurs went extinct about 65 million years ago,it was at the end of the Cretaceous period, which was a time of high volcanic and tectonic activity. There are a lot of theories why the extinction occurred. The most widely accepted theory is that an asteroid impact caused major climactic changes to which the dinosaurs couldn't adapt.

Dinosaurs probably live on today as the birds. All that's left of the dinosaurs are fossils and, perhaps,the birds. Dinosaur fossils have been found all over the world, maybe even near where you live!