As the Mesozoic progressed, more typically crocodile-like forms evolved. Dinosaurs were the dominant animals on land, but the proto-crocodiles flourished in rivers, swamps, and the oceans. These early crocodiles had far more diversity they have today. With the end Cretaceous extinction, the dinosaurs became extinct, except the birds, while the crocodilians continued with little change. Today, the crocodiles, alligators, and gharials are the surviving representatives of this lineage.