When Did Mammals First Evolve?

Mammals have been around on the Earth for a very long time. They were living at the time of the later dinosaurs, but these huge reptiles dominated the living world. When the global catastrophe, whatever it was, wiped out the dinosaurs 65 million years ago, the mammals were one of the few types of animal that were not killed off with them.

The catastrophe for the dinosaurs turned out to be an event that gave the mammal a whole new dimension. The environmental disaster obviously changed the landscape and living conditions and things became very harsh for life on Earth. Only the most adaptable were able to survive. Perhaps because they were small and warm-blooded, the mammals were adaptable and thrived in the new conditions.

With no dinosaurs or other large animals around, they were predator free. Many ate plants or other small animals and were able to multiply and evolve without hinderance for millions of years.

Mammals first evolved before time. It was before time was recorded so you cant really say when they first evolved but some scientists believe the evolved in about 4000 b.c.e

Around all long time ago