Section 35.2 Today’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