Winther, Wade, Dimond Online Appendix

Winther, Wade, Dimond Online Appendix

ONLINE APPENDIX: Evidence for the existence of two distinct debates

“Pluralism in evolutionary controversies:

styles and averaging strategies in hierarchical selection theories”

Rasmus Grønfeldt Winther, Michael J. Wade, Christopher C. Dimond

Biology and Philosophy, 2013

Consider a simple bibliographic analysis of some important works concerned with the units of selection debate:

(1) The historical foundations of the units of selection debate can be easily discussed without substantive reference to the material basis of the Wright-Fisher debate. For example, Lloyd 2000a provides a succinct introduction to the history withoutcitations to either Fisher or Wright. However, Lloyd 2000b and 2005b briefly discuss the later Wright (1980) (and cite Wright 1929 and 1931 in passing), because he draws the distinction between selection among groups for group advantage versus selection among groups for individual advantage. This distinction is crucial to the ‘adaptation for’ logic of the units debate. Fisher (1958) is listed in the bibliography but not in the text.

(2) Sober and Wilson's 1998 book on group level adaptation does not cite Fisher. Only Wright's (1945) book review of Simpson's Tempo and Mode in Evolution is cited, and then only for its “model of altruism” (1998, 59-60).

(3) Regarding hierarchical selection, Keller (1999) has numerous discussions on the “common good”, various forms of individual and group conflict, and selection operating in opposite directions at different levels, but little discussion of Fisher and Wright or of complex genetic models. The handful of references to Fisher concern sexual selection or sex-ratio evolution, matters closely tied to the concept of “adaptation for…” and selective function, rather than to complex genetic models. This case clearly fits into the discussion of ‘adaptation for…’ since Keller investigates only those cases in which the levels of selection are in opposition. Although his work has more extensive citations to Fisher, the topics cited, sexual selection and sex ratio evolution, are not topics addressed in the Wright-Fisher debate.

(4) Okasha (2007) uses the Price equation and cites four papers by Wright as well as Fisher (1958). Moreover, Okasha is clearly aware of important complex genetic issues, where the Wright-Fisher debate intersects the units of selection controversy (e.g., MLS1 and MLS2, from Damuth and Heisler (1988), the contextual approach, from Goodnight, Schwartz, and Stevens (1997)). And although his discussions of these matters tend to be framed in terms of the idealized philosophical units of selection debate, he is an exception because he references both literatures. Okasha’s work cites both literatures and may or may not fit our classification. Our analysis is based on central or general tendencies, and should not be force-fit on every important contributor to the debates on hierarchical selection.

(5) There may be other exceptions to the tendency of two distinct literatures. For instance, Uyenoyama and Feldman (1980) present detailed single-locus models of the evolution of altruism. Although they do not analyze the concept of “adaptation for…”, they are clearly concerned with the units of selection debate, arguing that “...distinctions between individual selection, kin selection, and group selection arguments at least in this case derive primarily from differences in emphasis.” (p. 396) They also cite, and use, Wynne-Edwards (1962), Williams (1966), and Dawkins (1976), all key referents in the units debate. Theirs is a biological reference primarily concerned with the units of selection debate in the framework of single-locus models, as opposed to complex, genetic models; it does not discuss the differences between Fisher and Wright.

Examples (1) – (2) from the philosophical literature on the units of selection debate bolster our claim regarding scant cross-referencing. The reciprocal lack of cross-referencing is also clear: obviously, Fisher and Wright's early work did not draw upon later philosophy of biology literature. Furthermore, the contemporary Wright-Fisher literature also tends to ignore the philosophical literature. Further analyses of citation patterns and discourse clusters using data science software would be useful, and are in process (e.g., collaboration with Carl Bergstrom and Jevin West, University of Washington: http://www.eigenfactor.org/map/maps.php).

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