The Evolution of Cooperation insects, where the workers – which are sterile, and therefore incapable of passing on their genes – benefit the queen, who is essentially passing on copies of "their" genes. This is further elaborated in the "selfish gene" theory of Richard Dawkins, that the unit of evolution is not the individual organism, but the gene. (As stated by Wilson: "the organism is only DNA's way of making more DNA.") However, kinship selection works only where the individuals involved are closely related; it fails to explain the presence of altruism and cooperation between unrelated individuals, particularly across species. In a 1971 paper
Alternatives to evolution by natural selection 1969 paper by Jack Lester King and Thomas H. Jukes, provocatively but misleadingly titled "Non-Darwinian Evolution". It provided a wide variety of evidence including protein sequence comparisons, studies of the Treffers mutator gene in "E. coli", analysis of the genetic code, and comparative immunology, to argue that most protein evolution is due to neutral mutations and genetic drift. According to Kimura, the theory applies only for evolution at the molecular level, while phenotypic evolution is controlled by natural selection, so the neutral theory does not constitute a true alternative. The various alternatives to Darwinian evolution by natural selection were not