Dinosaurs were big reptiles that lived a long, long time ago. Some were huge and others were small. They lived on land and in the sea, but they are now extinct, which means they don’t live on ...

At the start of the period, dinosaurs ruled the loosening remnants of the supercontinent Pangaea as rodents scurried at their feet through forests of ferns, cycads, and conifers. At the end of the ...