Crocodiles, the last dragon(2010)

Crocodiles appeared about two hundred million years ago. They coexisted and hunted the large dinosaurs and are the last survivors of the group of archosaurs, which means "ruling reptiles", a group that also included the dinosaurs and pterosaurs - flying dinosaurs - and more. They overcame geological cataclysms, planetary climatic changes, continental drift and even humans action. What made them surpass all their contemporaries and last until today?