Uniqueness and Phylogenesis of the Plague Microbe Yersinia pestis

The phylogenies of the plague microbe ( Yersinia pestis ), reconstructed on the basis of an advanced molecular genetic (MG) approach, are not congruent with the facts accumulated by classical scientific areas: ecology, biogeography, paleontology, epizootiology, and others. The MG approach cannot name the original host of the plague pathogen and reliably characterize the root of the phylogenetic tree. This deficiency is compensated by the ecological (in a broad sense) (ECO) approach, which operates with such ecological, phylogeographic, and biogeographic categories as geographical population, subspecies, range, ecological niche, and direct kinship. Y. pestis , the “blood dweller” of warm-blooded rodent hosts, is transmitted through flea bites and is unique in the family of predominantly intestinal bacteria Yersiniaceae (Enterobacteriaceae). According to the ECO approach, its uniqueness is associated with the origin in the populations of its primary host, the Mongolian marmot ( Marmota sibirica ), in unique circumstances, in which the marmot population was infected with pseudotuberculosis not by the traditional alimentary way in grasslands, but in a traumatic way during hibernation. The identification of the original host of the plague pathogen opens up broad prospects for studying its evolutionary history (speciation and intraspecific diversification) and improving the methodology of ecological, geographic, phylogeographic, and phylogenetic studies of this especially dangerous pathogen.