Prehistoric time

Prehistoric times are the time before history was recorded.They are divided into three periods. The oldest era was the Paleozoic era,in which fish,amphibians and reptiles appeared.Next came the Mesozoic era, which was the age of giant reptiles and dinosaur.The third era, which is called present one, is called the Cenozoic era.It is the age of mammals and bird.

Our knowledge of these based on the study of fossils.You can see these fossils in the big museums of the world.