BIOL 1010 Lecture Notes - Lecture 5: Genotype Frequency, Sexual Selection, Disruptive Selection
Document Summary
End of lecture 3&4 slides and start of lecture 5 slides. Sexual selection/preservation of variation: fitness is more than survival. Sexual selection: effectively a special case of natural selection, competition for mating opportunities, results in adaptations that increase in mating success, but can actually reduce chance of survival. Intrasexual selection: competition within one sex (usually males) for mating opportunities. Intersexual selection: one sex (usually females) chooses mate from (competing members of) other sex. Armaments" and ornaments": armaments: give you an advantage in combat, ornaments: designs on males that are attractive to females, sexual dimorphism: females and males look different from one another. Preservation of variation: natural selection driving out certain variations (unfavourable) Preserving allelic variations: diploidy hides" recessive alleles from selection when they are rare, natural selection cannot drive a recessive trait to extinct, e. g. cystic fibrosis example (lec. 3): q = ~0. 02; ~1 in 25 europeans are carries; only.
