Ans. The Triassic period from 252 million to 250 million years ago saw the rise of reptiles and the first dinosaur. While the Jurrasic Period from about 200 million to 145 million years ago, saw the rise in birds and mammals. And the Cretaceous period from about 145 million to 65 million years ago is renowned for its iconic dinosaurs, such as the Triceratops and Pterosaurs such as Pteranodon.