Mammalian Adaptations

MONOTREMES“Egg laying”

Duckbilled PlatypusAnteaterEchidna

MARSUPIALSPremature babies develop in pouch

Found in Australia/ New Guinea

• Kangaroo

• Wallaby

MARSUPIALSOnly North American Marsupial

• Oppossum

PLACENTALEmbryos nourished inside mother by

placenta

95% of all mammals are placental

At least 18 orders

Incisors- Chisel like teeth for cutting

Canines- Pointed teeth for puncturing/tearing

Premolars- Shred and grind

Molars- Flat teeth for grinding, crushing

TEETH

Specialized teeth vary with diet

Grass eaters have different teeth than carnivores

SALIVARY GLANDS

• DIGESTION starts in the MOUTH

Image from: http://www.entnet.org/healthinfo/throat/salivary.cfm

BALEENThin keratin plates

that hang from the roof of the mouth and screen food from water

Image from: http://home.iprimus.com.au/readman/whale.htm

ECHOLOCATIONBats can fly without eyes, but NOT

without ears

Bats emit high frequency sound waves that bounce off objects

Can determine size, distance, direction, speed

RUMEN

In cud chewers like cows, sheep, goats, giraffes

First chamber of stomach containing bacteria to digest plants

Image from:http://arbl.cvmbs.colostate.edu/hbooks/pathphys/digestion/herbivores/rumen_anat.html

CECUM

In non cud chewers like horses, rabbits, rodents, elephants

Small pouch off small intestine containing bacteria to digest plants

Human appendix is vestigial cecum

PRIMATES Larger Brain

Grasping hand with fingernails instead of claws

2 forward facing eyes

Includes:•Gorillas•Monkeys•Lemurs

PRIMATES

Humans are primates too!

PINNIPEDSCarnivorous

streamlined body

flipper limbed

Seals WalrusesSea lions

UNGULATESMammals with Hooves

CETACEANSIncludes:

whales, dolphins,

porpoises

CHIROPTERA

BATS

Only mammals that can fly