exam2. review

is natural seleciton adaptive or nonadaptive

it is adaptive

are chimps monkeys or apes

they are apes

species

individual group of organisms that can reproduce 

population

one species living in an area

what controls biomes

precipitation does, and precipitation controls vegetation 

homo sapiens

200000-800000 years ago, big brains, communication and problem solving

ardipithecus ramidus

4.5 mya, had changes in skeleton to show bipedal, but was still arboreal 

Australopithecus

is fully bipedal and fully terrestrial

when did hominids diverge form their common ancestor 

7 mya, and it was chimps 

homo erectus

1 mya, controlled fire, cooked food, used tools 

Allens rule

different species, individuals are going to skinner and longer closer to the equator i.e hotter areas, but arctic hares want to be rounder so they can trap heat in

Bergmans rule

same species, white tailed deer, Florida is skinny vs in Canada its thicker. Florida its really hot. worried about cooling off instead of staying warm.

is Bergmans rule and Allens rule natural selection

yes, the rules are natural selection, and different sized groups

when is vitamin d created

when exposed to uv light 

lighter skin tones

gets more vitamin d because they aren’t worried about folate being destroyed because they are at the poles where there isn’t much uv light 

darker skin tones

much more uv light, have darker skin with more melanin so they can absorb the uv light and keep their folate alive.

folate

stored in the body and is destroyed by uv light 

what absorbs uv light

melanocytes in the epidermis level

lightskin vs darkskin in geography

light skin vs dark skin in different portions of the earth and what are we trying to protect

hybrid breakdown

hybrids cannot be generations for long term so they die out

sympatric speciatoin

living In the same system, capable of interacting if they wanted to, decide to stop interacting and diversify

allopatric speciation

deviation of one species into two due to a geographical barrier

genetic drift + two forms

bottle neck and founder, any random chance event that changes the gene pool

gene flow, genetic drift and mutation

non adaptive