The epoch spans the time between 65 million and 56 million years ago.

Paleocene

Explanation:

This epoch is the first major worldwide division of rocks, it was after the Cretaceous Period and before the Eocene Period. There is a lot of information of this period enviroment and terrestrial life provided by the rock record in North America but the animals such as mammals are not well studied. There seasons in this period were defined by the lack or not of wet, there were not reptilians or dinosaurs but the mammals evolution was pretty fast.