“Just So Stories:” Richardson Against Evolutionary Psychology

Why do men find young women more attractive than older women? Why do women find high status men more attractive? The answer from recent evolutionary psychologists is that younger women are more likely to be fertile and healthy, and their progeny are more likely to survive. Thus, natural selection, acting primarily on our Pleistocene huntergatherer forebears, has led men’s preferences to be driven by genetic makeup to optimize the chances of their genes being preserved. Women’s preferences, by contrast, have been selected by the need to insure long-term care for offspring. The book at hand is a critique of such explanations, written by a philosopher of science, and directed at the weakness of evidence that such arguments display. The arguments, says Richardson, are “just so” stories, perhaps plausible but lacking in the kind of evidence required by biological accounts of evolution by natural selection. Evolutionary psychology is poor science, by the standards of evolutionary biology. Richardson is not the first philosopher of science to undertake a critique of evolutionary psychology. Starting with Phillip Kitcher’s (1985) attack on sociobiology through David Buller’s (2005) attack from the standpoint of psychology, philosophers of science have been withering in their criticism of evolutionary psychology. Richardson joins this literature using the standards of biological explanation as the ground for his attack. He brings to the task a wide knowledge of biology and a critical eye for the kinds of accounts that can count as explanation supported by empirical evidence. What’s wrong with evolutionary psychology’s explanation of men’s and women’s preferences? The short answer, according to Richardson, is that the kinds of evidence needed to test the claim are absent and that alternative explanations are not given sufficient weight. Thus, “if men preferred older women, that could be ‘explained’ by pointing out that older women are ‘proven’ as mothers” (p. 143). Further, evolutionary psychology is criticized for being excessively adaptationist, ignoring “spandrels,” developmental alternatives, and other, non-selectionist, mechanisms. Instead, the presence of complexity in human behavior, cognition, and language is assumed to be the result of evolution by natural selection, usually with reference to selection factors that operated in the Pleistocene. Richardson does not deny that natural selection is important (as he makes clear in the Introduction and throughout the book), nor that all human characteristics are ultimately the product of evolution. Still, he claims that an adaptationism results from the exclusive focus on just one mechanism of evolution (see especially pp. 53–59). Adaptationism is a bias because it rules out explanations based upon, for example, the emergence of complexity from the dynamics of simpler processes played out in developmental time. For example, rules of inference could be based on natural selection of “cheater detection” modules, as Cosmides and Tooby claim, but they could also arise as a byproduct of early learning, which could establish social rules for reasoning about social contracts. Cosmides and Tooby have not ruled out the alternative explanation, according to Richardson. The adaptationist bias is, in turn, accompanied by characteristically weak evidence provided in support of a natural selection account. For example, differential mate preferences among men and women are assumed to have resulted from selection as the only available explanation. But, says Richardson, there has been a failure to specify what the presumed adaptations are adaptations for, nor are Evo Edu Outreach (2008) 1:340–341 DOI 10.1007/s12052-008-0059-2