The term selfish gene was coined by Richard Dawkins (b. 1941) in his 1976 book of that name to convey the central sociobiological idea that it is reproductive success, rather than individual excellence, that determines the course of evolution. Thus "the survival of the fittest" does not really mean the survival of outstanding individuals themselves. It means the prevalence of their type in later generations through increasing numbers of descendants.

Biologists such as J. B. S. Haldane (1892–1964) had suggested this understanding of evolution as a solution to the "problem of altruism"—that is, the question how it was possible for animals often to act in ways that sacrificed their own individual interests to those of others around them. This undoubtedly happens, not only in the care of the young but in many other social activities. How had the trait developed? The answer lay in reproduction. Tendencies to act...