Frozen Evolution. Or, that’s not the way it is, Mr. Darwin. A Farewell to Selfish Gene.

The fitness of an individual is determined in the vast majority of cases not by the presence of a particular allele of one particular gene, but rather by its genotype, i.e. the combination of all its genes.When we ignore the possibility of mutation changes, the individual genes are copied and passed on to the next generation quite accurately.The structure of the genes is inherited from one generation to the next.In contrast, the genotype of sexually reproducing organisms is inherited only very approximately; in each generation, the genes derived from two different individuals are mixed together and thus a new and quite unique genotype is created.The quality of the genotypes of the parents has already been tested, as these parents survived to reproductive age.In contrast, a great many of the newly created combinations of genes, i.e. newly formed genotypes, could be completely or partly unviable.The existence of this segregation and recombination burden, i.e. the necessity of eliminating, by selection, in each generation, individuals with unsuitable genotypes, formed as a consequence of disintegration of combinations of cooperating chromosomes in segregation of  chromosomes by reduction division (meiosis) and combination of mutually cooperating genes on a single chromosome by recombination, once again places sexually reproducing organisms at a disadvantage compared to asexually reproducing organisms (Maynard Smith 1978).