The Dobzhansky Muller model provides an explanation for why hybrids have low fitness.

Last updated: 7/8/2022

The Dobzhansky Muller model provides an explanation for why hybrids have low fitness. Which description below accurately represents this explanation? a. Two populations diverge at a single locus, such that one population is fixed for the ancestral homozygous genotype (AA) while the other population is fixed for a derived genotype (aa). The "Aa" hybrids, however, are low fitness and therefore the populations are reproductively isolated by underdominance at a single locus b. Two populations diverge, such that their hybrids have an unfit combination of alleles at two or more loci. Divergence at these loci does not require underdominance, but rather an epistatic interaction that renders hybrids low fitness c. Two populations converge, such that hybrids have numerous recombinations of alleles at various loci. This results in hybrids with low fitness d. None of these statements correctly describes the Dobzhansky Muller model