Speciation Exam 4

Question 1

Acquire new alleles by

Answer 1

mutation and gene flow

Question 2

Genetic drift has bigger impact on what population

Answer 2

small

Question 3

Relative abundance of alleles altered by

Answer 3

genetic drift and natural selection

Question 4

Stabilizing selection example

Answer 4

predators attacked too dark and too light mice not the inbetween

Question 5

Directional selection does what

Answer 5

-acts against one phenotype
-environmental change

Question 6

populations that potentially interbreed under natural conditions, produce fertile offspring

Answer 6

Species

Question 7

Prezygotic barriers does what

Answer 7

block mating or fertilization

Question 8

behavioral isolation is also the same as

Answer 8

mate recognition
*example- fireflies respond to pattern of their own species, not to others

Question 9

mechanical isolation is

Answer 9

a physical incompatibility between reproductive organs of two organisms

Question 10

gamete isolation is when

Answer 10

the egg and sperm are released but a zygote is not formed

Question 11

temporal isolation is when

Answer 11

two or more species reproduce at different times

Question 12

5 prezygotic barries are

Answer 12

habitat, temporal, mechanical, gametic, behavioral

Question 13

Postzygotic barriers is when

Answer 13

mating occurs, zygote formed, but hybrid doesn’t survive or is not fertile

Question 14

2 Postzygotic barriers are

Answer 14

non viable hybrid and infertile hybrid

Question 15

speciation is

Answer 15

formation of new species

Question 16

Adaptive radiation is

Answer 16

many diverse species may arise from common ancestors

Question 17

Larger changes in a small populations gene pool due to random events is called

Answer 17

genetic drift

Question 18

Natural selection usually for phenotypes that

Answer 18

favor survival

Question 19

Directional selection example

Answer 19

all dark fur survives but light doesnt

Question 20

Reproductive isolation ensures

Answer 20

evolutionary independence from other groups
example-frogs only mate with frogs who croak like themselves

Question 21

habitat isolation is when

Answer 21

distinct habitats within same general area
*example- terrestrial, aquatic garter snakes don’t meet each other often

Question 22

geographic isolation prevents

Answer 22

gene flow

Question 23

requirements of separation are

Answer 23

-reproductive isolation of population
-genetic divergence

Question 24

habitat differentiation reduces

Answer 24

gene flow and genetic divergence follows