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Class Mammalia. Mammals. C haracteristics. Fur or hair Sweat glands Mammary glands (females) Most important mammalian characteristic Diaphragm for breathing Use various combinations of fur, hair and subcutaneous fat to conserve body heat. Three main categories 1: Placentals.
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Class Mammalia Mammals
Characteristics • Fur or hair • Sweat glands • Mammary glands (females) • Most important mammalian characteristic • Diaphragm for breathing • Use various combinations of fur, hair and subcutaneous fat to conserve body heat
Three main categories1: Placentals • The young develop inside female uterus attached to a placenta = largest group
Three main categories2: Marsupials • Young are tiny an underdeveloped; they crawl to the female pouch, attach to a nipple an finish development there
Three main categories3: Monotremes • The young develop inside of eggs (similar to reptile eggs) • Most primitive group, 3 species left • (platypus and 2 kinds of echidna)
Adaptations for movement • Land • Well developed muscles and bone • Skeleton is also highly flexible • Limb structure permits ease of motion and speed • Cat family: has grasping claws for climbing and holding prey • Snowshoe hair: elongated hind limbs for hopping in the snow • Grazing animals have modified toes to help with speed
Flight • Only bats • Have membrane between bones of wings
Water • Whales, dolphins and porpoises • Front limbs have become flippers • Tail propels through water • Streamlined body allows for speed • Blowhole instead of mouth • Otters and seals have similar adaptations but no blowhole
Digestive system:ruminants (cow, moose, deer, camels) • 4 chambered stomach • First two chambers for bacterial fermentation • Food regurgitated for more mechanical breakdown before entering last two chambers • Last two chambers for chemical digestion • This is necessary because they live off of grass which is hard to fully digest