Lecture 4:
Fitnesses that vary in time:
-
Diploid: protected polymorphisms:
- Consider the situation when q is close to 0
- A2 mainly in heterozygotes
- Marginal fitness A2, close to the fitness of heterozygote
- Marginal fitness A1, close to the fitness of A1A1 homozygote.
,Diploid: protected polymorphisms
- Then, analogous to the haploid case, one can show:
,-
, Spatial variation in fitnesses
- Levene’s model:
o Individuals spend their life in a niche/environmental patch
Own environment
Own selection
o Emerge from niche only to mate
At random
Each niche contributes fixed proportion
o This is soft selection as the extent to which individiuals are eliminated by section in a
niche has no effect on its output
o In contras ot hard selection in which each niche contributes to the mating population
(slide 8)
Fitnesses that vary in time:
-
Diploid: protected polymorphisms:
- Consider the situation when q is close to 0
- A2 mainly in heterozygotes
- Marginal fitness A2, close to the fitness of heterozygote
- Marginal fitness A1, close to the fitness of A1A1 homozygote.
,Diploid: protected polymorphisms
- Then, analogous to the haploid case, one can show:
,-
, Spatial variation in fitnesses
- Levene’s model:
o Individuals spend their life in a niche/environmental patch
Own environment
Own selection
o Emerge from niche only to mate
At random
Each niche contributes fixed proportion
o This is soft selection as the extent to which individiuals are eliminated by section in a
niche has no effect on its output
o In contras ot hard selection in which each niche contributes to the mating population
(slide 8)
