Dinosaurs: How they became extinct Something happened 65 million years ago, at the end of the Cretaceous period, something so devastating that it altered the course of life on earth. It seems like it happened so sudden, as geologic time goes, that almost all the dinosaurs living on earth disappeared. So how did these dominant creatures just die off? Was it a slow extinction, or did it happen all of the sudden? These questions bring rise …showed first 75 words of 398 total…

…showed last 75 words of 398 total…