Mammals - whales, monkeys, and humans. These mammals have a...

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Mammals Members of the class  Mammalia  are animals that have hair and nourish their young with milk  produced by mammary glands. The presence of body hair or fur helps maintain a constant body  temperature in the homeothermic mammals.  Several types of mammals exist: the monotremes, marsupials, and placentals.  Monotremes  are  egg-laying mammals that produce milk. The duck-billed platypus and the spiny anteater are  examples. They are both found in Australia and probably developed during the geographic isolation  of this continent.  Marsupials  are mammals whose embryos develop within the mother's uterus for a short period of  time before birth. After birth the immature babies crawl into the mother's abdominal pouch where  they complete their development. Animals such as the kangaroo, opossum, and koala bear are  marsupials.  The  placental mammals  include many familiar animals, such as rabbits, deer, dogs, cats, bats, 
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Unformatted text preview: whales, monkeys, and humans. These mammals have a placenta: a nutritive connection between the embryo and the mother's uterine wall. Embryos are attached to the placenta, and they complete their development within the mother's uterus. Mammals have spread to virtually all environments on earth ranging from the oceans to the deserts. They live underground, on the ground surface, in trees, and in the air. Mammals have a highly developed nervous system, and many have acute senses of smell, hearing, taste, vision, and touch. Mammals rely on memory and learning to guide their activities. They have been able to develop numerous appropriate responses to different environmental situations. They are considered the most successful animals on earth today....
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This note was uploaded on 11/11/2011 for the course BIO 101 taught by Professor Pesthy during the Fall '07 term at Texas State.

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