Accepted_test

The existence of stable differences in a uniform selection area seems somewhat paradoxical from the population genetics view; however, it is precisely disruptive selection that can give such divergence. Examples of population systems with stable divergence of genetic structures of subpopulations inhabiting a homogeneous area are found in nature. Comparing these observations and modeling results allows us to explain the maintenance of the stability of natural genetic divergence by the interaction of disruptive selection (in the form of reduced fitness of hybrid forms) and weak migration process. The results of experiments performed by Altukhov and co-authors with populations of Drosophila melanogaster, in which primary divergence of the genetic structures of the subpopulation was obtained at the α-GDH locus, are in good agreement with this statement. One can assume that disruptive selection, in this case - reduced fitness of α-GDH heterozygotes, played a significant role in maintaining this divergence. An alternative hypothesis is the fixation of differences by genetic drift.

On the one hand, to identify and substantiate the possibility of the presence of this factor in the system, and on the other hand, to assess how significant a role disruptive selection plays in maintaining the stability of primary genetic divergence, in this work we analyzed mathematical models of the dynamics of allele frequencies in a large panmictic population and a system of local migration-coupled populations, and also compared the model dynamics of allele frequencies under the action of selection and without it with the data obtained in the experiment.