Reptiles
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Reptiles • Class Reptilia • Snakes, lizards, turtles, tortoises, crocodiles, alligators • Amniotic egg…leathery shell protects water environment inside • Dry, scaly skin prevents water loss
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Reptiles. Class Reptilia Snakes, lizards, turtles, tortoises, crocodiles, alligators Amniotic egg…leathery shell protects water environment inside Dry, scaly skin prevents water loss. Reptiles. Circulation (2 closed systems … pulmonary and systemic) - PowerPoint PPT Presentation
Transcript of Reptiles
Reptiles• Class Reptilia• Snakes, lizards, turtles, tortoises,
crocodiles, alligators• Amniotic egg…leathery shell
protects water environment inside
• Dry, scaly skin prevents water loss
Reptiles• Circulation (2 closed systems …
pulmonary and systemic)– Heart 3 chambers in snakes and
turtles (septum divides ventricles and
minimizes blood mixing)– Heart 4 chambers in crocodiles
Reptiles• Respiration… lungs divided into
lobes…many small sacs (alveoli) greater surface area for
respiration.• Brain very well developed,
especially cerebrum (front area, controls movement)
Reptiles• Thermoregulation
– Ectothermic…absorb heat from surrounding, so body
temp. is close to surroundings (used to be called cold blooded)•Amphibians and fish are ectotherms,
too.
Reptiles• Reproduction:
– Most oviparous…lay eggs that develop on their own
– Some ovoviviparous…keep egg in body to develop and lay
close to time of birth– Few viviparous…live birth
Reptiles• Class: Chelonia:
– Turtles and tortoises• Class Squamata:
– Lizards and snakes• Class Rynchocephalia:
– Tuatara• Class Crocodilia
– Crocodiles, alligators, caimans
Class: Chelonia:Turtles and tortoises
Class Squamata:Lizards and snakes
Class Rynchocephalia:Tuatara
Class CrocodiliaCrocodiles, alligators,
caimans
Birds• Class Aves• Evolved about 150 million years ago• Forelimbs modified to wings• Lightweight skeleton (hollow/fused bones)• Closed circulatory system with 4
chambered heart…no mixing of oxygenated/deoxygenated blood…higher
metabolism/movement• Large, well developed brain
Birds• Endothermic (temp 104 – 106 oF)• Lungs and air sacs• Oviparous (lay eggs)• Feathers (and skin) cover body
– Flight, down, contour feathers• Digestive organs include: crop, 2
stomachs (#2…gizzard has stones in it)
Order AnseriformesSwans, ducks, geese
Order Sterigiformesowls
Order Apodiformeshummingbirds
Order PsittaciformesParrots, parakeets, macaws,
cockatiels, cockatoos
Order PiciformesWoodpeckers, toucans
Order PasseriformesMost familiar….robins,
wrens, cardinals
Order CiconiiformesHerons, storks, ibises,
egrets, penguins
Order GalliformesTurkeys, pheasants, chickens
Order StruthioniformesOstrich, emu, rhea
Mammals• Class Mammalia• Evolved 300 million years ago• Hair (and skin) body covering• Endothermic• 4 chambered heart (closed
circulatory system)• Females produce milk for young
Mammals• Specialized teeth for different jobs• Lungs with alveoli (small sacs like
reptiles)•Diaphragm (muscle below
ribcage) helps breathe• Brain about 15 times heavier
than same sized fish, amphibian or reptile!
Mammals• 3 groups of mammals
– Monotremes: Oviparous (lay eggs), e.g. duck-billed platypus
– Marsupials: viviparous (young born immature, develop inside mother for some time), e.g.
opposum, kangaroo– Placental: viviparous (young fed in
uterus by placenta), most mammals you think of
Order Xenarthra• Anteaters,
armadillos, sloths• 30 spp
Order Lagomorpha• Rabbits, hares,
pika• 70 spp
Order Rodentia• Mice, squirrels,
chipmunks, rats• Largest Order,
over 1800 spp
Order Primata• Monkeys,
gibbons, apes, humans
• 235 spp
Order Chiroptera• Bats• 900 spp
Order Insectivora• Shrew,
hedgehogs, moles
• 390 spp
Order Carnivora• Dogs, cats, bears,
sea lions, otters, seals, hyenas
• 274 spp
Order Artiodactyla• Deer, cattle, giraffe,
pig, camel• Even # toes on hoof• 210 spp
Order Perissodactyla• odd # toes on hoof• Horse, rhino, zebra• 17 spp
Order Cetacea• Whale, dolphin,
porpoise• 90 spp
Order Sirenia• Manatee,
duogong• 4 spp
Order Proboscidea• African and Asian
elephants• 2 spp
Order Montremata• Lay eggs• Platypus,
echidna• 3 spp
Order Marsupiala• Have pouches• 280 spp• Opposum,
kangaroo, koala bear
