Mammals are the most intelligent creatures on earth. They learn to adapt to many different climates and living conditions. Some mammals are tame, some are wild, some are very large and some are small.

Mammals are alike in these ways:

• They have fur or hair.
• The babies drink milk from their mother's bodies.
• They have a backbone.
• They have four limbs (arms, legs, flippers).
• They are warm-blooded. (Warm-blooded means that their bodies stay at almost the same temperature all the time.)
• Most mammals are born alive.
• They breathe air through lungs.
• **Most baby mammals grow inside their mother and are born alive. There are a few mammals that grow inside an egg in their mother's body.
  

Bears, apes, wolves, the hippopotamus, rodents (rabbit, gopher, chipmunk ), lions, tigers, whales, dolphins and people are all mammals. Some unique mammals are whales, dolphins, bats, the armadillo and the platypus.