Not by Genes Alone: How Culture Transformed Human Evolution
Richerson, Peter J. and Boyd, Robert
University of Chicago Press: Chicago, IL, 2005
ISBN 0226712842 (pb)
Reviewed by Giangiacomo Bravo in
Journal of Artificial Societies and Social Simulation, vol. 10, no.1, 2007.
There remains much about evolution that is not yet understood, including the cultural dimension of human evolution.
Richerson and Boyd answer to the question takes the form of a comprehensive theory of cultural evolution, based on Darwinian foundations and possibly able to uncover many of the mechanisms that link human biology with its unique ability to use cultural tools.
. . . the authors’ choice of limiting the formal analysis does not alter the deep rigor of their arguments, at the same time making the reading possible for a wider public, especially from the humanities. And that is the good news, since this work really represents a bridge between natural and social sciences, deriving the evolutionary tools from the former ones and applying them to one of the core problem of the latter: human culture in all its forms. The authors’ aim (both meritorious and necessary) of filling the existing gap between the two realms of science is explicit. In their words, “the most fundamental questions of how humans came to be the kind of animal we are can only be answered by a theory in which culture has is proper role and in which it is intimately intertwined with other aspects of human biology” (p. 4, emphases in the original).
According to the reviewer, there are two main arguments of the book. The first is addressed to those engaged in evolutionary theory, emphasizing the ways in which cultural evolution differs from genetic evolution, and the necessity of understanding culture for understanding human behavior. The second is addressed to social scientists who frown on evolutionary explanations. Note:
Genes and culture are probably strictly linked in a long co-evolutionary process that produced modern humans. This means that not only human psychology should have genetic bases that permit and support cultural evolution, but that the latter, once in place, contributed to modify the original environment in a way that influenced subsequent genetic change. Evidence of strong recent (< 40, 000 years) selection on human phenotypes represents a first confirmation for this idea (Wang et al. 2006). If confirmed by other studies, gene-culture co-evolution would represent a key model for the explanation of some of the H. sapiens species peculiarities, including the unusual propensity of its members to cooperate in large groups of unrelated individuals.
This is admittedly a tentative theory. My question is: what took you folks so long?