The Adaptationist Program

The adaptationist program comes in two forms. In the forward form, the scientist postulates an environmental problem, then searches for the solution to the problem in the organism's phenotype. In the backward form, the scientist starts with a known phenotypic solution, then searches for the environmental problem that could have produced it (Lewontin, 1979).

As an example of the backward form of the adaptationist program, we know that birds have wings, so we can reason backward to try to uncover the environmental problem to which wings are a solution. Heat regulation is such a problem. Early wings allowed birds to capture or release heat, thus allowing them to live in either cold or hot environments. As another example of the backward form of the adaptationist program, we know that human infants smile, cry, follow, approach, cling, etc. Each of these behaviors has the effect of increasing proximity with the caregiver, so we can reason backward to try to uncover the environmental problem to which proximity to the caregiver is a solution. Protection of the infant from predators is such a problem. In the ancestral environment in which the species emerged, infants who did not maintain proximity with their caregivers did not survive to reproduce.

Problems in the Adaptationist Program

Sociobiologists have failed to recognize or adequately deal with several major problems inherent in the adaptationist program. The first set of problems is problems with description. Descriptions are inherently theory-laden. Concepts such as entrepreneurship, slavery, dominance, aggression, tribalism, and territoriality, referred to routinely by sociobiologists, may have no independent existence whatsoever in the world of organisms (Lewontin, 1979).

Problems with description come in four varieties: arbitrary agglomeration, reification, anthropomorphism, and reductionism. First, arbitrary agglomeration is describing something, e.g., the hand, as a single unit of anlaysis, when in fact natural selection may operate rather on its constituent parts, e.g., the thumb.

Second, reification is assuming that mental constructs, such as property or terrioriality, are the objects of natural selection, when in fact, "specific mental constructs are not real objects" (Lewontin, 1979, p. 8). The status of "more tribal than" differs qualitatively from the status of "heavier than" (Lewontin, 1979).

Third, anthropomorphism occurs when concepts that originally referred to human social relationships, e.g., rape, are applied to non-human animals. When thus applied, the concepts necessarily lose their human historical and cultural meaning. However, sociobiologists often, upon finding that a condition like "rape" occurs in non-human animals like mallards, proceed to claim that an evolutionary basis or genetic predisposition has been found for the human condition referred to by the same word (e.g., Barash, 1979). To do this is to conflate the original meaning of the word "rape" with a derived, metaphorical meaning (Lewontin, 1979). There appears to be no common mechanism or common function between "rape" in mallards and in men. Therefore, the entire case seems to rest upon the question-begging terminology (Kitcher, 1987).

Fourth, reductionism is the assumption that properties of collective social organizations arise from the properties of their constituent individuals (which themselves arise from the individuals' genes). For example, war (aggression of one society against another) is supposed to arise from individual aggressive feelings. In an analysis of the behavior of tribes and nations, Wilson (1978) concludes that "humans are strongly predisposed to respond with unreasoning hatred to external threats and to escalate their hostility sufficiently to overwhelm the source of the threat by a wide margin of safety" (p. 119). Reductionism makes it impossible for sociobiology to deal with uniquely social properties. For example, social revolution occurs at a rate too rapid to be explained by genetic variation alone (Lewontin, 1979).


Barash, D. (1979). The whisperings within. New York: Penguin.

Kitcher, P. (1987). Précis of Vaulting ambition: Sociobiology and the quest for human nature. Behavioral and Brain Sciences, 10, 61-100.

Lewontin, R. C. (1979). Sociobiology as an adaptationist program. Behavioral Science, 24, 5-14.

Wilson, E. O. (1978). On human nature. Cambridge, MA: Harvard University Press.

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