mating systems Flashcards
what is a mating system
any pattern of male-female pairings
describes how male and female interactions are built around choosing mates
females invest heavily in each of a:
where as males invest little in each of a:
small number of gametes
large number of gametes
males produce
large number of small motile sperm
females produce
small number of eggs w large investment in each; leads to mate choice
natural selection favoured small and fast motile gametes; to balance this:
large nutrient rich gametes gives rise to large, well developed offspring
protandrous
males early in development, females later, like clownfish
protogynous (gyn first)
females when smaller, then males when larger
sex carries a high evolutionary cost:
cost of meiosis (splitting the genome up)
sexual reproduction ____ genes are passed on, asexual reproduction ____ genes passed on
half, all
intersexual selection (between different sexes)
effects that mating preferences of one sex have on the characteristics of the other ex mate attraction and mate choice
intrasexual selection (within same sex)
effects of competition within one sex for mates, ex combats, displays
any trait preferred by females will be
strongly favoured
females should make their choices among males based on the likelihood that mating w the chosen male will
enhance the survival of the female’s offspring; good genes passed on
bad boy phenomenon
male attractiveness rather than gene quality is the currency –> explanation: sexy sons more likely to get matings BUT bad boys don’t make good dads
what factors go into mate choice (10)
- species identification
- good genes
- inbreeding avoidance
- optimal outbreeding
- resources
- symmetry
- immuno- competence
- immuno- complementarity
- quality as a parent
- sexy son