Mammals are warm-blooded. In contrast to a cold-blooded animal, the mammal’s brain control their body temperature. Mammals also have hair and mammary glands. In addition, most mammals have seven cervical vertebrae, lungs for breathing, a neocortex in the brain, and have live births.
Mammals belong to the phylum Chordata. Mammals can be broken down into three major groups:
- Monotremes: egg laying mammals (e.g. platypus and echidna).
- Marsupials: pouched animals (e.g. kangaroo and wallaby) with short gestation times.
- Eutheria: the placental animals (e.g. whales, elephants, rodents, apes, hooved animals) with long gestation times.
There are about 4,200 mammal species today.
They live in a wide variety of environments. This includes living on land, in the water, in trees, and in the air. They are found in hot tropical and cold polar ecosystems.
Mammalia and Humans
Humans are mammals. The non-human mammals are of importance to the human species. These other mammals are an important source of food. For some human societies they are also an important source of farm labor or transportation.
Many mammals have been domesticated. Dogs and cats are also important as pets to humans. Pets provide companionship to humans.
Improving Your Reading and Thinking Skills
Think for a few moments. Try to recall the major ideas in this article. When you are done, click the box below for a list of main ideas.
How did you do? With practice, you should be able to identify many of the major ideas. You may even discover some important ideas that aren’t listed.
Hall of Mammals, UC Berkeley.