But the biggest development in the seas was the appearance of whales in the mid- to late Paleogene. The huge animals evolved from land mammals that took to the seas. Meanwhile, smaller reptiles ...

Several factors contributed to the survival of crocodiles, turtles, lizards and birds 66 million years ago, say our readers ...

The class of animals that we refer to as “reptiles ... during the early part of the Paleogene period. The ancient mosasaur, a giant marine lizard, was a formidable predator that thrived ...

This event occurred across the world and witnessed the loss of around 75 percent of all species of animals during a very narrow point of time – the boundary between the Cretaceous and Paleogene ...