[Evolution as resistance to entropy. II. A conservative role of the sexual reproduction].
It is claimed that biological meaning of the sex and meiotic genetic recombination is a creation of a barrier for evolution. The transition to sexuality is not merely a change in reproduction mode but a leap to a new known as cohesion. In a sexual population, the lineages of different individuals become tangled into multidimensional net, resulting in a creation of gene pool and new superindividual entity--biological species. A sexual individual can not reproduce its particular genocopy and its fitness is sacrificed to some extent for the fitness of the species. The competition between individuals is replaced with the competition between gene alleles given that the competitors have after all the common offspring. The genotype of the "outstanding" individuals with a highest fitness are not transmitted to next generation, being scattered and shuffled in new combination after unavoidable crossing with the "ordinary" partners. So, the sexual reproduction can evolve only as a whole. Genetic recombination in meiosis changes a character of mutations distribution among gametes enhancing the classes with mutation load both lower and higher than average. By this, an efficiency of the truncated selection (elimination of the individuals with multiple mutations) is enhanced and an ability to restore the initial genotype appears. Evolution within the species becomes reversible, which is equivalent to its virtual cessation. The species acquires an evolution resistance that can be overcome by rare concurrence of circumstances.
Shcherbakov
V P
VP
D000818:Animals; D005075:Biological Evolution; D019277:Entropy; D009154:Mutation; D011995:Recombination, Genetic; D012098:Reproduction / Q000235:genetics / Q000502:physiology*; D012100:Reproduction, Asexual / Q000235:genetics / Q000502:physiology