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
The Genetical Theory of Natural Selection wrote that it was "certain to take rank as one of the major contributions to the theory of evolution." J. B. S. Haldane described it as "brilliant." Reginald Punnett was negative, however. The book was largely overlooked for 40 years, and in particular Fisher's fundamental theorem of natural selection was misunderstood. The work had a great effect on W. D. Hamilton, who discovered it as an undergraduate at the University of Cambridge and noted in these excerpts from the rear cover of the 1999 variorum edition: The publication of the variorum edition in 1999 led to renewed interest in the