Introduction Look around you sometime, the chances are that if you see an animal it is a mammal. Mammals are the dominant life form on this planet at the moment, at least from a human perspective. There are about 4260 species of mammals known on this planet at the moment, though taxonomists are still arguing.
Mammals however are big.
You can see them easily, and perhaps most importantly you are one. They fascinate and horrify us. We eat them, ride them, keep them as pets, makes clothes out of them, hunt other mammals with them and use them as substitutes for ourselves in scientific, particularly medical, research. To most people animals are mammals. Our mammalian cousins are very important to us.