Class Mammalia

General Characteristics• Bilaterally symmetrical• __________• Mammary glands (produces milk)–Nurse young

• Endothermic (warm blooded)• ____________________• Dioecious–Internal fertilization

• Heterodont dentition–Specialized teeth

• ______________________• Produce a placenta (usually)

________________________ 6 Major Orders:

1.) Order Rodentia2.) Order Artiodactyla3.) Order Carnivora4.) Order Cetacea5.) Order Primates6.) Order Monotremata

Order Rodentia Rodents!

Mice, squirrels, gophers, beavers, & guinea pigs

________________ Have continuously growing incisors

____________ = front teethMust chew to keep short

• Have a short breeding cycle• _____________________

Order Artiodactyla• Pigs, hippos, camels, deer, sheep,

etc.• 220 species• _______________

• Mostly herbivorous/grazing animals–_______________________•Are omnivorous

Order Carnivora

• ________________________!• Canines, cats, bears, raccoons,

seals, otters, walruses, etc.• 260 species• Are predatory

• __________________________• Have special teeth and/or claws

to take down prey

Order Cetacea

• Whales and dolphins• Have blubber for insulation• ______________________• All aquatic• Highly intelligent

• Use sonar to locate food

Order Primates• Gorillas, chimps, orangutans,

humans, monkeys, lemurs• _______________• Adaptations for tree-living–Strong limbs with opposable

digits

• ___________________• Extensive parental care

Order Monotremata

• Duck Billed Platypus and Echidnas (spiny anteater)• Only mammals to lay eggs• Have a single opening called a cloaca for

urination, defecation, and reproductive• Platypus has a poisonous barb on the

back foot

Order Monotremata

Echindas

Poison Barb