Lecture Final exam Past review sheets Flashcards Preview

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Flashcards in Lecture Final exam Past review sheets Deck (7)
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1
Q

what is biological species concept?

A

a group of populations whose members have the potential to interbreed in nature and produce viable, fertile offspring

2
Q

distinguish between prezyogtic and posyzygotic reproductive barriers

A

prezygotic blocks fertilization and postzygotic prevents development of zygote

3
Q

5 prezygotic reproductive barriers and examples

A

1) habitat isolation (garter snakes, one on land and one on water)
2) temporal isolation (spotted skunk)
3) behavioral isolation (blue footed boobies)
4) mechanical isolation (shells of 2 snails)
5) gametic isolation (sea urchins)

4
Q

explain how hyrbrid breakdown maintains separate species even if gene flow occurs

A

offspring of hybrids may be weak/sterile. may be present but cannot become genetically independent.

5
Q

describe some limitations of the biological species concept

A

extinct forms cannot be tested. Asexual forms are isolated, period.

6
Q

what is allopatric speciation?

A

physical separation results in speciation due to reproductive isolation

7
Q

what is sympatric speciation?

A

divergence in place due to instrinsic factors such as sexual selection, habitat differentiation and polyploidy