Exam 2

Question 1

what two things do not maintain genetic variation

Answer 1

selection

drift

Question 2

what maintains genetic variation as natural selection decreases

Answer 2

migration-selection balance

mutation-selection balance

Question 3

what maintains genetic variation as natural selection increases

Answer 3

heterozygote advantage
frequency-dependent selection
fluctuating selection coefficient

Question 4

mixing of two good strains of DNA

Answer 4

hybrid vigor

Question 5

heterozygote advantage _____ variation and leads to a ____ genetic polymorphism

Answer 5

maintain

stable

Question 6

decreases genetic variation
unstable equilibrium
drives alleles to be fixed

Answer 6

heterozygote disadvantage

Question 7

which allele wins in the heterozygote disadvantage

Answer 7

the most common

Question 8

relative fitness depends on the frequency of the genotypes themselves

Answer 8

frequency dependent selection

Question 9

fitness increases as a genotype becomes rare

Answer 9

negative frequency dependence

Question 10

fitness increases as a genotype becomes common

Answer 10

positive frequency dependency

Question 11

what is an example of negative frequency dependency (2)

Answer 11

predation

sex ratio

Question 12

what is an example of positive frequency dependency

Answer 12

pollinators

Question 13

fitness isn’t constant over time

Answer 13

fluctuating selection coefficients

Question 14

how are fluctuating selection coefficients different from frequency dependent selection

Answer 14

because things are not fluctuating because freq but bc of an external factor

Question 15

multiple phenotypes arise from the same genotype

Answer 15

polyphenism or phenotypic plasticity

Question 16

multiple phenotype in the same populations

Answer 16

polymorphism

Question 17

multiple loci affect the same trait

Answer 17

polygenic

Question 18

what causes differences in phenotype: nature or nurture

Answer 18

both

Question 19

natural selection acts on phenotypes

Answer 19

true

Question 20

process that requires a fertilization event in which two gametes unite

Answer 20

sexual reproduction

Question 21

process of reproduction where offspring are produced from a single parent and offspring are nearly identical gentic copies of parent

Answer 21

asexual reproduction

Question 22

is asexual reproduction an ancestral trait of all organisms

Answer 22

yup

Question 23

what are the 3 theories for the advantage of sexual reproduction

Answer 23

-speed rate of adaption
allows adaption to changing environment
prevent mutational deterioration

Question 24

common asexual genotypes show ______ parasite infection rate

Answer 24

higher

Question 25

removal of deleterious mutations is called | what size population does it work in an why

Answer 25

muller's ratchet | small because of genetic drift

Question 26

selection for traits that lead one sex maximize its mating success

Answer 26

sexual selection

Question 27

based on bateman-trivers theory maximum number of offspring is lmtd by _____ in males and _____ females

Answer 27

number of females he can mate with | number of eggs she can produce

Question 28

males and females have different potential for repoductive success

Answer 28

differential reproductive success

Question 29

male with more than one female mate

Answer 29

polygyny

Question 30

females with more than one male mate

Answer 30

polandry

Question 31

higher opportunity for mating success leads to a ____ selection for sexual dimorphism

Answer 31

greater

Question 32

what are the four reasons for sexual selection

Answer 32

fundamental asymmetry in parental investment difference in variance in reproductive success selection acts on fitness variance phenotypic consequence is sexual dimorphism

Question 33

males strive against each other leads to evolution of armaments increases access to females

Answer 33

intrasexual selection

Question 34

females mates non-randomly due to preference for male traits | leads to evolution of male ornaments

Answer 34

intersexual selection

Question 35

sex subject to strong selection will ______ and those subject to weaker sexual selection will be _____

Answer 35

compete for mates | choosy

Question 36

what are alternate strategies for intrasexual selection

Answer 36

sneaker males she male garters cheating

Question 37

examples of intrasexual selection DURING mating

Answer 37

speedier sperms sperm hooks cloaca pecking infantacide

Question 38

examples of intrasexual selection POST mating

Answer 38

sperm plugs mate guarding amplexus

Question 39

what are the 4 main theories for female choice

Answer 39

good gene model sexy son hypothesis direct selection model sensory bias model

Question 40

male trait is assoc w/ direct fitness adv | ie bringing female food or helping raise kids

Answer 40

direct selection model

Question 41

exploiting pre-existing biases in female sensory system

Answer 41

sensory bias model

Question 42

trait is representative of good genes sons AND daughters are more fit few empirical tests that show offspring w/ higher fitness

Answer 42

good genes model

Question 43

sons will have high reproductive success due to being more attractive daughters will gain a preference for that trait

Answer 43

sexy son hypothesis

Question 44

which theory for female choice can lead to runaway selection | why

Answer 44

sexy son | bc it accelerates sexual selection

Question 45

inbreeding and genetic drift are important for conservation

Answer 45

true

Question 46

mating between close relatives

Answer 46

inbreeding

Question 47

what type of frequency changes under inbreeding | which does not

Answer 47

genotype | allele

Question 48

negative effects of inbreeding on offspring

Answer 48

inbreeding depression

Question 49

how does inbreeding lead to inbreeding depression

Answer 49

increases genetic homozygosity

Question 50

probability that 2 alleles are identical by descent

Answer 50

inbreeding coefficient

Question 51

does inbreeding always cause inbreeding depression

Answer 51

nope

Question 52

what are two ways that an increase in homozygosity occurs in individuals

Answer 52

deleterious recessive alleles | loss of benefits of heterozygosity

Question 53

inbreeding leads to an ______ vortex

Answer 53

extinction

Question 54

how to hermaphrodites avoid inbreeding

Answer 54

don't breed as both sexes at once | gametic incompatibility

Question 55

games don't work on themselves which leads to inhibition of fertilization

Answer 55

gamete incompatibility

Question 56

purging of deleterious recessives from a population via inbreeding

Answer 56

purifying selection

Question 57

what four ways do evolutionary novelties arise

Answer 57

enhancement reduction/loss change in growth rates change in function

Question 58

making things bigger relative to body size

Answer 58

enhancement or elaboration

Question 59

differential rates of growth over time

Answer 59

heterochrony

Question 60

retention of juvenile traits in adults

Answer 60

neoteny

Question 61

structure co-opted for a different use

Answer 61

exaptation

Question 62

what genetic changes are responsible for evolutionary innovation

Answer 62

repurposing the function of genes | change genes that regulate gene expression

Question 63

how does the repurposing of gene function occur

Answer 63

duplication and divergence

Question 64

gene that has been duplicated within a genome that evolved to have a new function

Answer 64

paralog