[Species-forming involution of pathogenic bacteria as a biological pattern (exemplified by bacteria of the genus Moraxella)].

The author advances a hypothesis stating that a species disappearing as a result of new conditions evolving in a colonized animal or human body, unfavorable for the existence of this species, does not become extinct, but reverts into newly developing species due to the loss of its properties and acquiring new properties corresponding to new conditions. Thus the genus is preserved through the loss of species characteristics by individual organisms. The advanced hypothesis is substantiated by the analysis of the relevant processes observed in cases of infectious keratoconjunctivitis in humans and cattle, caused by bacteria of the genus Moraxella. The data indicating the possibility of such reversion in the genera Neisseria and Bordetella are presented.