BIOL 2704 Lecture Notes - Lecture 2: Population Genetics, Transposable Element, Genetic Drift
Document Summary
Lecture 2 how populations evolve (part ii) Most evolutionary models are much simpler because they focus only on genes: highly stable, easy to measure and categorize. Since everything dies exactly once, genes don"t change during your life (sort of), and inheritance is generally fair (mendelian). So, we can focus on lifetime reproductive success and inheritance. Absolute fitness number of offspring produced over an individual"s lifespan. If two alleles at a locus cause differences in fitness, then the one with higher fitness will tend to increase in frequency at the expense of the other. Interesting complications: natural selection & genetics have some surprises, let"s measure the average fitness (represented by w) of three genotypes. Two alleles, a and b, at one locus: waa = 1. 5, wab = 1. 6, wbb = 1. 7, setup: large population with p(a) = 0. 99 and p(b) = 0. 01.
