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 Evolution of God of God. Among other things, Wright discusses the role of evolutionary biology in the development of religion. Geneticist Dean Hamer hypothesized that some people have a specific gene that makes them prone to religious belief, which he calls the God gene, and that over time natural selection has favored these people because their spirituality leads to optimism. Wright, however, thinks the tendency towards religious belief is not an adaptive trait influenced by natural selection, but rather a spandrel - a trait that happens to be supported by adaptations originally selected for other purposes. Wright states that the human brain approaches