vertebrates pt 4 (birds -> humans)

class aves includes what animals? what subphylum do they belong to? what phylum do they belong to?

birds

subphylum vertebrata

phylum chordata

what evolutionary modifications have birds gone through to enable them to fly?

no urinary bladder + females have 1 ovary + gonads are small until breeding season

toothless

hollow bones

wings, NOT feathers

endotherm

animals that generate heat from inside their body

birds are endotherms, meaning what?

they use their metabolism to maintain their body heat

what are some unique characteristics of birds?

they have the best eyesight of all vertebrates

there are several species that are flightless

→ emu, kiwi, rhea, ostrich, penguin

what birds are flightless?

emu, kiwi, rhea, ostrich, penguin

class mammalia contains what animals? what subphylum do they belong to? what phylum do they belong to?

platypus, echidnas, opossums, kangaroos, koalas, bandicoots,

subphylum vertebrata

phylum chordata

what are some characteristics of class mammalia?

mammary glands + hair + differentiation of teeth

fat layer under the skin + diaphragm to ventilate lungs

endothermic with high metabolic rates + large brains

are birds and mammals endotherms?

yes

what are 3 groups in class mammalia?

1) monotremes

→ platypus, echidna

2) marsupials

→ opossums, kangaroos, koalas, bandicoots

3) eutherians

→ humans, dogs, cats, elephants, zebras

where are monotremes found?

australia + new guinea

what are unique characteristics of monotremes?

they are the ONLY mammals that lay eggs

they have hair + produce milk but LACK nipples

→ milk is produced by glands in their belly and clings to the fur

where are marsupials found?

australia

north + south america

what is the only marsupial found OUTSIDE of australia?

opossums

→ found in north + south america

what is a unique characteristic of marsupials?

marsupials are born pre-maturely

they finish their development while nursing in the marsupium (pouch)

what are the unique characteristics of eutherians?

they have a placenta + a longer period of pregnancy than marsupials

→ the embryonic development is COMPLETED WITHIN THE UTERUS

evolutionary convergence

if the environment is the same, two animals that are different may share similar traits

→ for instance, in australia there are marsupial kangaroos. but in north + south america, there are eutherian patagonian cavies. both look almost exactly the same but they have slightly different evolutionary characteristics

what characteristics to primates have? what group do they belong to?

hands + feet for grasping 

flat nails instead of claws

skin ridges (fingerprints)

larger brains

short jaws

→ eutherians

monkeys and apes are the only primates to have what feature?

opposable thumbs

hominoids are a group of primates and primates are a group of eutherians. what animals are contained in the hominoids?

gibbons, orangutans, gorillas, chimpanzees, bonobos, humans

how do humans DIFFER from hominoids?

they stand and walk upright

we have larger brains capable of language + symbolic thought + use of complex tools

reduced jawbones + jaw muscles

shorter digestive tract

*we are 99% identical to chimpanzees

what has allowed humans to survive?

our brains