The mosasaurs ruled the ocean in the late Cretaceous period. ... Mosasaurs went extinct 65.5 million years ago in the same mass extinction event that wiped out the dinosaurs, Live Science previously reported.

Why did the mosasaurs go extinct?

Freshwater mosasaurs like Pannoniasaurus grew as large as crocodiles and probably competed with crocs for the same resources. ... About 92 million years ago, an extinction event occurred that was caused by large-scale underwater volcanic activity.

Which dinosaurs are still alive today?

Other than birds, however, there is no scientific evidence that any dinosaurs, such as Tyrannosaurus, Velociraptor, Apatosaurus, Stegosaurus, or Triceratops, are still alive. These, and all other non-avian dinosaurs became extinct at least 65 million years ago at the end of the Cretaceous Period.