Hardy Weinberg Equilibrium

exam 3

Population is in HWE if…

no microevolution, no selection, no gene flow, random mating, and a large population

Microevolution - mutation

new alleles increase heterozygosity

Microevolution - genetic drift

lowers allelic richness and therefore lowers heterozygosity

Microevolution - gene flow

immigration of alleles leads to an increase of heterozygosity

Microevolution - non random mating

choosing for a specific trait decreases heterozygosity

assortative non random mating: choosing a mate based on shared similar or dissimilar traits ( increasing homozygotes)

disassortative non random mating: dissimilar phenotypes mating more regularly than expected leading to an increase in heterozygotes

Evidence for HWE

observed matches expected (no microevolution present)

Evidence against HWE

observed does not match expected (microevolution observed)