Section 35.2Today’s Mammals

Grouped by reproduction

Monotremes Most primitive mammals All modern monotremes live in

Australia Egg-laying mammals Three types: Duck-billed platypus and two types of

spiny anteaters

Reproduction…

Marsupials

Most live in Australia Babies finish development in

mother’s pouch Kangaroos, wombats, koalas,

possums

Reproduction…

Placental mammals

Most advanced mammals Live all over the world on land

and in oceans Young develop inside mother’s

uterus, attached to a placenta

Main Placental Mammal Groups

Rodents – gnawing mammals; 40% of all placental mammals; rats, mice

Bats – flying mammals with front legs modified into wings; most eat insects, some fruit; use sonar for navigation

Insectivores – insect eaters like shrews; small with very fast metabolism

Main Placental Mammal Groups…

Carnivores – meat eating mammals, include cat family (lion, tiger) and dog family (wolf, fox); strong and very intelligent

Pinnipeds – marine mammals with flippers for swimming that return to land to reproduce; walrus, seal, sea lions

Primates – forward facing eyes, grasping hands; apes, monkeys, humans

Main Placental Mammal Groups…

Ungulates – hoofed mammals, grazing animals; some with an even number of toes (deer), others with an odd number (horse); many chew cud to continue digesting tough plant material

Cetaceans – marine mammals that spend entire life in sea; two groups – toothed whales (hunters) and baleen whales (filter feeders)

Main Placental Mammal Groups…

Lagomorphs – long legs for jumping; rabbits and hares

Sirenia – barrel-shaped marine mammals; manatees

Elephants – long nose (proboscis) two groups – African and Asian