Earth's Geologic Eras
What Are the Three Eras of Geologic Time in Order?

Learn the three major eras of geologic time—Paleozoic, Mesozoic, and Cenozoic—and their significance in Earth's history.

Ancient Life Forms
What Life Existed Before Dinosaurs? Exploring Prehistoric Eras

Discover the ancient life forms before dinosaurs, from single-celled organisms to early fish during Precambrian and Paleozoic times.