Abstract :
Drawing on the results of research and published data in this paper, we have examined the rate of occurrence of polyploids (genome mutation) in Lumbricidae. As is shown, the frequency of occurrence of polyploid karyotypes (46) almost equals that of diploids (52). Comparing the geographic distribution of these forms, exemplified by Eisenia nordenskioldi (Eisen), the following tendency become evident: polyploid races, as a rule, tend to occupy the margins of the species range. In cases of sympatry of diploids and polyploids of the same species, they tend to take up different ecological niches. Hence, genetic diversity results in species diversity, with polyploid races of the same species being, in fact, sibling species.
