Fig 4. Inbreeding results in a decay of heterozygosity.

After one generation of inbreeding, half of the offspring retain the heterozygosity found in the parent while half become homozygous. As diversity cannot be restored in homozygous regions in the absence of outcrossing and heterozygosity decays by half each generation, population-level heterozygosity continually declines in inbreeding populations until all lineages are homozygous.