(began 65 million years ago)
The Paleocene Epoch began after the extinction of the dinosaurs. Mammals that had lived in the shadows of dinosaurs for millions of years eventually evolved into a vast number of different forms to fill the newly vacant environmental niches. Many early mammal "designs" of this time would soon become extinct; others would survive and then evolve into other forms. The variety of birds, other animals, and plants increased, and species became more specialized. Although dinosaurs were gone, reptiles lived on in the form of turtles, crocodiles, lizards, and snakes.
At the beginning of the Paleocene, most mammals were tiny like this rodent-like multituberculate. With time, mammals grew in size, number, and diversity.
continue to Eocene