Mills of God model of origin of sexuality
One of the possible explanations of long-term survival of sexuality in the population is based on the same principle. The relevant model, which we will term the Mills of God model, was first described in detail by J. Maynard Smith (Maynard Smith 1993); however, he attributed authorship to M. Williams and G. Price. According to this model, the newly emerging parthenogenetic mutant originally has twice the fitness of its sexually reproducing competitor. However, wedging out the competitor took many dozens of generations in a large population. During this time, the traits of the members of the parthenogenetic clone did not change much, because the only source of its microevolutionary variability consists in rare mutations. In contrast, a population of sexually reproducing individuals permanently generates genetic variability and thus basically exhibits greater microevolutionary plasticity. Consequently, suitable adaptations are formed in time, allowing it to wedge out the parthenogenetic clone.