sexual selection and sexual conflicts Flashcards
intrAsexual selection
male to male competition
intERsexual selection
choose females to select the best mate
how are best mates chosen
directly through dominance or best territory
indirectly through courtship behaviour to advertise fitness advantage through a song or plumage
what is batemans principle
females are choosy
female fertility limited by nutrition, more invested in her eggs
males fertility limited by the females
what is runaway selection
a genetic model of sexual selection
what does runaway selection explain?
male trait and female prefernce may have no fitnes advantage
it might actually lower population fitness
pointless evolution
what is the indicitor hypothesis
genetic model of sexual selection
what does the indicitor hypothesis say
male traits are honest signals of fitness
this incrases the population fitness as the males traits are correlated to this and the mating isnt random
what happens to the population in the runaway hypothesis
the females choose male traits
leading to a decrease in population fitness
what happens to the population in the indicator hypotheisis
females chose meals based on their fitness
leading to the population fitness increasing, yay
describe the lex paradox
heritable variation in fitness must exist but is expected to disaprea quickly as good genes spread to fixation
what si the sexual conflict
males have advantage to keep mating again and again
females after mating for first timelose fertility yet keep mating
this is described as cryptic female choice
what is female cryptic choice
females experience a drop in fetility after they first mate
yet continue to mate anyway
describe sexual conflict
sperm competitiion + sperm choice = sexual selection
what leads to polyandry
the intessity of sexual selection is greater for the sex which invests the least in producing and rearing offspring
what is antagnosistic seduction?
females evolve resistance to seduction
counter adaptation
round and round in arms race
females evolve and adapt to be favoured then there is counter adaptation making the males favoured
what is post copulatory cryptic female choice
female choise increases the females fitness
males directly provide benefits such as care or gifts
male fitness doesnt need to be heritable
what is the evidence for female sexual confict
ejaculate ejection
no choice in resisting the mating but can the eject the ejaculate of the make
the females can choose the sperm they want
what direct gifts can males give feamesl
nuptial gifts:
nutrient reources
what benefits do nuptial gifts hae
incraesed longevity egg production growth less predation risk gift evolve to maximise mating effort or paternal investment
what do nuptial gifts reduce
sperm competition
providing the gift secures the offspring as yours
delays the female mating again
