Reproduction

Front 1

How is female repro investment initially greater?

Back 1

1. lactation (huge caloric investment)
2. size of gamete (egg= bigger, less motile)
3. gestation

Front 2

early nurturing of embryo/child

Back 2

necessarily female dominated (esp in mammals)

Front 3

additional matings after first

Back 3

valuable to males, not females

Front 4

variance in reproductive success

Back 4

mean has to be the same
sd is diff in males/females

Front 5

elephant seals- variance in male repro success (HUGE)

Back 5

Dec: males fight, go w/o food, est. dominance hierarchy
Jan: females arrive ready to mate
-top 4% of males get 85% of sex
-most males never copulate

Front 6

sex behavior predictions (2)

Back 6

1. sex that invests more will be more discriminating
2. sex that invests less will compete for access to other sex (will seek paternity certainty)

Front 7

"sex that invests more will be more discriminating"

Back 7

-demand honest signals of health (peacock feathers)
-value fighting ability (height, musculature- measures of dom)
-elicit a commitment to invest (courtship dance, nuptial gift)

Front 8

b/c female repro investment initially higher/vulnerable early on, expect...

Back 8

evolution of choosiness, demands for investment

Front 9

why are some signals "honest"

Back 9

b/c of opportunity costs

Front 10

"sex that invests less will compete for access to other sex"

Back 10

1. competition for access

2. mate guarding/extended mating
-increase likelihood that subsequent investment worthwhile

3. sperm competition/anti-sperm

Front 11

sperm competition

Back 11

females mate with multiple males, directional selection for increased sperm production (large testes)

-vagina plug, toxic to sperm of other males

Front 12

initial low investment, paternity uncertainty of males

Back 12

competition for access

indiscriminate mating

mate guarding, sperm wars

*vulnerable b/c might be investing in another male's offspring