Mesozoic Era

The Mesozoic Era is a geological era that lasted from about 252 to 66 million years ago. It is often referred to as the "Age of Reptiles" due to the dominance of dinosaurs during this time period. The Mesozoic Era is divided into three periods: the Triassic, Jurassic, and Cretaceous.

Triassic Period

The Triassic Period lasted from about 252 to 201 million years ago. During this time, the first dinosaurs and mammals appeared. The supercontinent Pangaea began to break apart, leading to the formation of separate landmasses.

Jurassic Period

The Jurassic Period lasted from about 201 to 145 million years ago. It is known for the dominance of dinosaurs, including the large herbivorous sauropods and the fearsome carnivorous theropods. The earliest birds and the first flowering plants also appeared during this time.

Cretaceous Period

The Cretaceous Period lasted from about 145 to 66 million years ago. It saw the continued dominance of dinosaurs, as well as the emergence of new groups such as the duck-billed hadrosaurs and the armored ankylosaurs. The Cretaceous ended with a mass extinction event that wiped out the dinosaurs and many other species.

Study Guide

• What is the Mesozoic Era known as?
• Which are the three periods of the Mesozoic Era?
• What significant events occurred during the Triassic Period?
• What characterized the Jurassic Period?
• What major event marked the end of the Cretaceous Period?
• Describe the dominant life forms during each period.
• How did the supercontinent Pangaea change during the Mesozoic Era?

[Mesozoic] Related Worksheets and Study Guides:

• Geologic timeScience • Eighth Grade