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

During the evolution of any genome, genes could most probably be formed that would cause that their carriers exchanged genetic material with other organisms.While other genes were capable of spreading in the population only vertically in asexually reproducing organisms, i.e. from parents to offspring, through DNA replication, these mutated genes could also spread horizontally, i.e. from one individual to another (Hickey 1993; Bell 1993).One of the ways consists in transfer of a cytoplasmatic genetic agent, plasmid or virus with the relevant gene at the moment of physical contact of two cells.For example, during ciliate conjugation during exchange of nuclei between protozoa, the transfer of an infectious agent can occur very easily.A further type of horizontal spreading of a gene programming sexual reproduction is based on transfer of the gene from one chromosome to another within a single zygote by, for example gene conversion accompanying crossing-overs.The ability to force cells to reproduce sexuallyand thus create a precondition for horizontal spreading in the population is certainly advantageous for such a gene.It is thus probable that genes with this ability will be evolutionarily very successful and will be readily fixed by natural selection.It simultaneously makes no difference to the gene whether the actual process of sexual reproduction is or is not selectionally advantageous for the particular organism.Genes act selfishly; those that program their carriers so that they are themselves spread most effectively in the population are successful in evolution.