ZOOLOGY

 Endothermy  Hair  Completely divided heart  Milk – mammary glands  Single Jaw Bone  Specialized teeth

 Body temperature regulation through metabolism and insulation  Homeostasis  Allows mammals to live in cold climates  Allows for energy to perform strenuous activity for extended periods  Faster metabolism requires more food and oxygen

 Adaptations to environment - blubber – whales, seals - thick fur – polar bears - large ears – elephants - panting – lions, dogs

 Provides insulation and protection  Made of the protein keratin

 Efficient  Two atria  Two ventricle  Septum completely divides ventricles preventing mixing of oxygen rich blood and oxygen depleted blood.

 Mammary glands located on thorax  Milk contains carbs, proteins, and fats  Modified sweat glands

 Breakdown of food begins with chewing  Provides large surface area for enzymes to digest food  Incisors – cut  Canines – grip  Premolars – shear, cut, shred  Molars – grind, crush

 Lower jaw made up of one bone  Mammal fossils often identified by jaw bone

 Efficient  Large surface area  Two mechanisms – diaphram, rib-cage muscle

 Special adaptations for plant digestions  Rumen – four part stomach “chewing the cud”  Cecum – large sac branched from small intestine – allows for fermentation  Both utilize microorganisms

 Mammal brain 15 times heavier than fish, reptile or amphibian  Large cerebrum – evaluates input from sense organs, controls movement, regulates behavior

 Monotremes – oviparous  Marsupials – viviparous  Placental – longer development in uterus receives nourishment from placenta

 Monotremata  Marsupialia  Insectivora  Chiroptera  Dermoptera  Primates  Scandentia  Macroscelidea  Tubulidentata  Lagomorpha  Rodentia  Pholidota  Carnivora  Cetacea  Artiodactyla  Perissodactyla  Hyracoidea  Sirenia  Proboscidea

 Lay eggs  Ancient  Platypus  Two echidna species (spiny anteater)

 Super order marsupialia  Seven orders  280 species  Most live in Austrailia  Only U.S. species is the Virginia opossum

 30 species  Anteaters, armadillos, sloths  Feed on insects with long sticky tongue  Many are toothless  Have unique structure of lumbar vertebrae  Strong teeth, claws

 Rabbits, hares, pikas  Native to many countries  Double row of upper incisors that continue to grow  Herbivore

 Largest mammalian order  Found on every continent except Antartica  1800 species  Mice, rats, porcupine

 235 species  Apes, monkeys, lemurs  Humans  Forward facing eyes allows for dept perception  Wide range of sizes  Grasping hands and feet

 Only flying mammals  Bats  900 species  Modified forelimb  Echolocation  Large ears

 390 species  Shrews, hedgehogs, moles  Feed primarily on insects  Long pointed nose and sharp teeth allow them to hold prey

 274 species  Feed on meat  Strong jaws  Large teeth  Claws  Pinnipeds – aquatic carnivores (sealions)

 Ungulate  Even number of toes  Most are ruminants  Deer  Cattle  Giraffes  Pigs

 Ungulate  Odd number of toes  Horses  Zebras  Rhinos  Tapirs  Have a cecum

 Related to Artiodactyla  Whales, dolphins  Adapted to aquatic environments  Hairless except for snout

 Related to elephants  Look similar to whales due to convergent evolution  Live in tropical seas, estuaries, and rivers  Lack hind limbs

 Nose modified into long boneless trunk  Elephant  Asian and African  Modified incisors called tusks