Social semantics : how useful has group selection been ?

A greater understanding in evolutionary biology is often obtained by looking at the same problem in different ways (Maynard Smith, 1983). This fact is well established in the field of social evolution, where explanations for behaviours such as cooperation can be carved up in a number of ways, each with their own advantages (Frank, 1998; Sachs et al., 2004; Lehmann & Keller, 2006; West et al., 2007c). Wilson suggests that in our social semantics review (West et al., 2007b), we did not allow for ‘genuine pluralism,’ because we did not allow for group selection. As fans of pluralism (West et al., 1999), we would like to address this general issue, before turning to the specific criticisms of Wilson’s three suggested errors. First, as we emphasized in our original paper, we do not claim that group selection is incorrect. Our point was that although it can be a potentially useful tool (e.g. Gardner et al., 2007b), it frequently leads to confusion and time wasting (see below; West et al., 2007b, pp. 420–421 and 424–425). Second, Wilson’s (2007) paper is not a call for genuine pluralism; it is just a return to the old confusions about group selection, most of which were solved more than 20 years ago (Grafen, 1984; Frank, 1986b). There are some important pluralist issues within the field of social evolution, but Wilson does not address any of these. For example, the different ways in which direct fitness explanations for cooperation can be divided up (Sachs et al., 2004; Bergmüller et al., 2007; West et al., 2007c), distinguishing between the evolution and maintenance of traits (Boomsma & Ratnieks, 1996; West et al., 2007b), and the relationships between the whole range of theoretical methodologies (e.g. neighbour modulated, inclusive fitness, quantitative genetic, population genetic, multi-locus, etc.; Hamilton, 1964; Frank, 1998; Wolf et al., 1999; Gardner et al., 2007b; Taylor et al., 2007b). [Correction added after publication 28 November 2007: in the preceding paragraph, citations have been changed to journal style]. Correspondence: Stuart West, Institute of Evolutionary Biology, School of Biological Science, University of Edinburgh, Edinburgh, EH9 3JT, UK. Tel.: +44 131 6505496; e-mail: [email protected]