Kingdom Animalia Phylum Chordata Subphylum Vertebrata Class Mammalia

Characteristics of Mammals • • Endothermic-controlling metabolism & regulating heat loss Hair-all mammals have it for insulation & protection Cool off by panting or sweating Two-loop circulatory system w/4 -chambered heart completely divided • Several types of glands – salvia, sweat, oil, digestive enzymes, hormones, milk & scent. • Mammary glands – secret milk for young • Diaphragm – muscle below lungs to aid in respiration

More Characteristics • Single solid jawbone with specialized teeth according to diet • • • Pointed or chisel-like incisors Canines Premolars and molars • Nervous System • • • Cerebrum – largest part of brain – used for thinking & learning. Medulla oblongata – controls involuntary bodily functions Cerebellum – controls movement & coordination

Mammal Classification • Placental mammals – give birth to live young that have developed in uterus. Nourished from placenta. The time of development in the uterus is gestation. • About 90% of all mammals are placental. • There are 19 orders of placental mammals.

More Common orders of Mammals Rodentia –rodents, squirrels Edentata – anteaters, sloths, armadillos Lagomorpha – rabbits, hares Insectivora – shrews, moles Primates – lemurs, monkeys, apes, humans Chiroptera – bats –only flyer Artiodactyla –even # toes deer, elk, cattle, sheep Perissodactyla – odd # toes horses, zebras, rhinos Cetacea – whales, dolphins Sirenia – manatees, dugongs Proboscidea – elephant – two types African or Asian

© 2001 California Academy of Sciences Susan Middleton © 2003 Susan Middleton http: //elib.

Mammal classification • Order Marsupialia – viviparous • Two births- 1 st half inside mother and 2 nd half grows in pouch on outside of mother. • Kangaroos, opossums, koala • Australia, New Guinea, N. America

Mammal classification • • • Order Monotremata – monotremes – oviparous Duck-billed Platypus Spiny anteater (echidnas) Found only in Australia, Tasmania, New Guinea • Only three species of monotremes alive today.