Practice question

Assortative mating occurs when individuals choose mates phenotypically similar to themselves for particular traits or genetically similar background. Positive assortative mating increases mating between similar genotypes, resembling inbreeding effect, elevating frequency of homozygous genotypes and reducing observed heterozygotes compared with random expectation. Negative assortative mating does opposite, favoring dissimilar partners and increasing heterozygosity. Unlike disassortative mating that promotes diversity, positive assortment for a locus mimics autozygosity effect, raising both dominant and recessive homozygotes while allele frequencies themselves remain unchanged by mating system alone.