Evolutionary Psychology

Table of Contents

Evolutionary psychology is an evolutionary approach to human nature.
Attachment Theory is also grounded in certain evolutionary ideas, and Behavior Genetics is a field concerned with that all-important evolutionary mechanism, the gene.

Evolutionary Psychology and Sociobiology

One author summed up the basic idea of evolutionary psychology this way: "A person is only a gene's way of making another gene" (Konner, 1985, p. 48). Sociobiology (of which evolutionary psychology is a subfield that particularly concerns humans) can be thought of as having, like any
research program, a "hard core" of problem solving strategies that provide possible answers to vexing research questions, and a "protective belt" of promising research questions to be addressed by providing actual answers to these questions. The protective belt structures our ignorance by identifying research questions that must be addressed if the research program is to advance. Whereas the actual answers that arise from the protective belt may be wrong, the hard core (by methodological fiat) is never wrong--any potential negative evidence is to be blamed on faulty auxiliary assumptions rather than on the theory itself.

Sociobiology can be thought of as a special case of the adaptationist program, which assumes that all phenotypic features (or characters) of contemporary organisms result from the fact that these features allowed the organisms' predecessors to produce more offspring in a prehistoric environment (Lewontin, 1979). "Narrow sociobiology" is defined as the study of evolution and of function, and chiefly applies to non-human animals in which cultural transmission is not an important variable intervening between possible and actual explanations (Kitcher, 1988). The hard core of narrow sociobiology includes the following laws or problem solving strategies, the basics of evolutionary theory:

"Pop sociobiology" (represented by Wilson, 1975, 1978) comprises narrow sociobiology plus some additional machinary that allows one to go from evolutionary theory to "human nature" (Kitcher, 1987). The argument that allows one to progress from a behavior's maximizing fitness to a proscription on efforts to change the behavior through social engineering is called Wilson's ladder (Kitcher, 1987).

Levels 1 and 2 of Wilson's ladder together comprise the adaptationist program that Lewontin (1979) considers illegitimate, even in narrow sociobiology. According to the adaptationist program, natural selection generates optimal phenotypes. It is hard to find an interpretation of the adaptationist program (i.e., an argument for optimality) that is both nontrivial and true. The slogan "survival of the fittest" is not true, for, as Kitcher (1987) argues, "There may be no optimal phenotype, or the optimal phenotype may be coded by a heterozygote, or, if there are more than two alleles at a locus, the fitness relations among the genotypes may prevent the fixation of the fittest" (p. 66). Moreover, selection is not the only evolutionary force--there is also chance, the effects of which can be both large and permanent in small populations. In view of these considerations, a panglossian interpretation of the effects of natural selection ("we live in the best of all possible worlds") would be mistaken.

Most sociobiologists are genetic determinists, though some are more subtle than others. There are three waystations along the high road to genetic determinism: the doctrine of genetic fixity, the doctrine of innate capacity, and the doctrine of statistical variation. Each doctrine is more sophisticated than its predecessor (Lewontin, 1991).

Evolutionary ideas have been applied to human social relationships in a number of areas. Chief among these are mate selection and aggression.

~ Flip to top ~


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

Konner, M. (1985, October 6). One gene at a time. The New York Times Book Review, 48.

Lakatos, I. (1970). Falsification and the methodology of scientific research programmes. In I. Lakatos & A. Musgrave (Eds.), Criticism and the growth of knowledge (pp. 91-195). New York: Cambridge University Press.

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

Lewontin, R. C. (1991). Biology as ideology: The doctrine of DNA. New York: Harper Collins.

Wilson, E. O. (1975). Sociobiology: The new synthesis. Cambridge, MA: Harvard University Press.

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

~ Flip to top ~

Evolutionary Psychology Links

Evolutionary Psychology: Student Papers in This Website Evolutionary Psychology: Papers Elsewhere Evolutionary Psychology: Websites Elsewhere Evolutionary Psychology: Reference Sources
~ Flip to top ~

Last modified May 1998

Home to Great Ideas in Personality