Mammals live in many Environments MAMMALS ARE A DIVERSE GROUP MAMMALS ARE ENDOTHERMS MAMMALS HAVE ADAPTED TO MANY ENVIRONMENTS MAMMALS HAVE REPRODUCTIVE ADAPTATIONS

Mammals are a diverse group Mice, cows, elephants,chimps, bats, whales & you are all mammals. Some do well in cities, while others need very specific environments. Less than 5000 mammal species but come in many shapes & sizes, with different ways to move, find food and eat. All mammals: -have HAIR during some part of their life –Most have TEETH for consuming food –ALL produce MILK to feed their young

Mammals are Endotherms Use food to generate body heat & have adaptations to control body heat. Hair: may keep warm in cold (polar bear fur) or protect from extreme heat (camel hair) Soft, fluffy underhair keeps heat close to body; water- resistant guard hair covers underhairs & gives fur its color. Specialized hairs are used also –Whiskers (sensory touch hairs –Quills of porcupine for self defense.

Mammals are Endotherms, cont. Some mammals (like dolphins & whales) have little hair, but a layer of fat called blubber to help maintain body temperature. (insulates organs from heat & cold) Body fat also stores energy in mammals, in the form of fat cells. –Hibernating animals may eat a lot more when food is available. –This makes them fat, so while hibernating, they don’t have to eat, just live off their fat.

Mammals adapt to many Environments Some live underground: moles have strong claws to dig and can sense prey in the dark. Some live in trees: spider monkey can use its 4 limbs and tail to move through forest and never touch ground Some live in water: dolphins have blowhole, flippers & blubber to survive in water.

Mammals & Reproduction Reproduce sexually by finding a mate; may do this only certain time of year or all through the year. Internal fertilization, then offspring develops inside of female; usually a special organ (PLACENTA) transports nutrients, water & oxygen from mom’s blood to babies. Gestation = time it takes for baby to develop in mom before birth. Exceptions: platypus & spiny anteater have young hatching from eggs. Marsupials(opossum & kangaroos) have pouches where young finish developing after birth.

Raising Young Milk (high energy liquid food full of protein, fat, sugar & nutrients) is the first food young mammals consume. Mammary glands make milk in female mammals. For most mammals, only females care for young. Different mammals take different amounts of time to care for young before they’re on their own. (giraffes can walk as soon as born, seals nurse for only a month till on own, and humans take longest of all till are “on their own” without parents help.