The Mesozoic Era

The Mesozoic Era is often called the "Age of Dinosaurs." It lasted from about 252 to 66 million years ago. Dinosaurs ruled the land, pterosaurs ruled the sky, and giant reptiles ruled the oceans. This era is divided into three periods: Triassic, Jurassic, and Cretaceous.

Rise of the Dinosaurs

The Mesozoic began after the worst extinction in history. Life slowly recovered and dinosaurs appeared during the Triassic Period. By the Jurassic Period, dinosaurs had become the dominant land animals. The supercontinent Pangaea broke apart during this time.

A World of Giants

The Mesozoic was a warm time with no ice at the poles. Plants grew thick and lush. The first flowering plants and the first birds appeared. The first small mammals lived in the shadows of the dinosaurs. The era ended when an asteroid hit Earth 66 million years ago.

Fun Facts

• The Mesozoic Era lasted about 186 million years — over 900 times longer than humans have existed.
• The first birds, flowers, and mammals all appeared during the Mesozoic.
• The climate was so warm that palm trees grew near the North Pole.

Did You Know?

During the Mesozoic Era, the world was much warmer than today. There was no ice at the North or South Poles. Forests grew in places that are now frozen, like Antarctica!