Mechanisms/Rates Of Speciation P2 Flashcards
When it works with natural selection:
Direct benefit to females
Good genes hypothesis
Sensory bias
Competition for mates and access to fertilisation a that’s results in differential reproductive success
Sexual selection definition
When it opposes natural selection:
Fisherian runaway selection
Chase away selection
Natural selection favours fecundity and survival. Sexual selection favours:
Fertilisation a and mate acquisition
Sexual selection has differences in route and strength to natural selection, they are:
Faster and consistent direction
Does sexual selection build linkage disequilibrium?
More effectively yes
Can contribute and inhibit divergence?
Yes both
Provided it is ecologically divergent, sexual selection can generate what?
Prezygotic isolation
Ecological interactions with sexual selection are:
Food resources
Parasitism
Sensory bias
Predation
Mortality costs on sexual ornaments and affects female preference
Predation
Evolution of mating system affected by environmental factors eg polygamy
Food resources - clumped resources results in polygamy as females choose make with the most resourceful territory
Exploitation of host sexual signals
Parasitism
Females pay attention to ecological environment to aid mate choice
Sensory bias
Speciation and sexual selection are both hard to measure
So it is difficult to establish if sexual selection leads to speciation
Time For Speciation
Time for reproductive isolation to evolve once process has started