A Field Guide to Fossils of the Smoky Hill Chalk. Part 3: Marine Reptiles.

Several varieties of reptiles were well adapted for living and competing successfully in mid-ocean during the Late Cretaceous. It is likely that some, including mosasaurs, plesiosaurs and pterosaurs, were as highly evolved for survival at sea and in the air as the dinosaurs were on land. All marine reptiles were air breathers, and had to surface periodically in a manner similar to modern whales and porpoises. Leer más.