Family tree of the reptiles and their descendants

Family tree of the reptiles and their descendants

The reptile family began when the first hard shelled egg was laid about 310 million years ago. Since then reptiles have invaded the land, sea and air by evolving into a variety of fascinating and bizarre types. Only a few of them survive to this day. Mammals and birds can also trace their ancestry to early reptiles.

This chart illustrates the major branches of the reptile family tree, showing how the groups relate to one another and approximately when they evolved. The relative size of each group is not indicated. The bars of color that reach the top indicate the groups that are still living today.