The Cretaceous

In the Cretaceous the continents moved toward the places they are today, and shallow seas flooded large areas of land, including a seaway that split North America in two. Flowering plants appeared and spread.

More kinds of dinosaur are known from the Cretaceous than from any other period, among them Tyrannosaurus, Triceratops, Spinosaurus, Velociraptor and the giant titanosaurs of South America.

The period ended 66 million years ago when an asteroid struck what is now the Yucatan Peninsula in Mexico. Every dinosaur died out except the birds.