PSY352H5 Lecture Notes - Lecture 9: Stria Terminalis, Ovarian Follicle, Gonadotropin
Document Summary
But why are there two sexes and why do we have sex at all: couldn"t parthenogenesis be simpler, energy and time to find the right mate, competition among members of the same gender. There must be some evolutionary advantage behind sexual reproduction- what is it: genetic recombination. Increased flexibility (ie. better adaptation to environmental change) Strong selection pressure on reproductive behaviours: reduced genetic variance in reproductive behaviour, reduced phenotypical variability making reproductive behavioural responses more uniform (fewer surprises when encountering opposite gender) Mate selection and courtship: proper identification of the correct species. Mating systems: monogamy (1 male + 1 female, polygamy (1 partner + many mates, polygyny (1 male + many females, polyandry (1 female + many males, polygynandry (many males + many females) Inequality in costs of reproduction means gender dependent differential selection: female has to make sure her offspring gets the best genes, male needs to make sure his genes are passed to the largest number of offspring.
