Description Prehistoric Life. The Mesozoic Era was a period of approximately 187 million years divided up into three distinct periods-Triassic, Jurassic and Cretaceous. Dinosaurs multiplied and dominated Earth's animal kingdom. Millions of years have passed since they roamed the earth, but you can instantly revive the dinosaurs when you add these amazing animals to your class project or diorama display. 5 pcs. Ages 7 and up, adult supervision recommended with younger children. Model scenery materials
