Campbell's “evolutionary epistemology” is used more frequently to refer to extensions of Darwinism than other phrases, and his description of it as “variation and selective retention” is highly cited. However, we can still ask whether it is sufficient. The evidence from his classic essay is that he understood it to include somatic maintenance and reproductive growth, but omitted somatic growth and reproductive maintenance. We describe some of the complexity of the evolutionary ecology of life histories, including ecological and ecological versus social density-dependence and scale-dependence, and find that, interestingly, understood as a distinction between spending and investing, the traditional r versus K density-dependence distinction yields the same pattern of expected life history traits as does scale-dependence (although there should be other ways of distinguishing them). We then use this to fill in the missing somatic growth and offspring maintenance of Campbell's model of sociocultural evolution. In concluding, we emphasize the degree to which not only the evolutionary ecology of life histories but also the logic of population genetics and tree-building have been found relevant to the social sciences. Donald Campbell and David Hull, both now deceased, will be remembered as early modern pioneers of the theory of Darwinian sociocultural evolution.
CampbellDT. 1965. Variation and selective retention in socio-cultural evolution. In: BarringerHRBlankstenGIMackRW editors. Social change in developing areas: a reinterpretation of evolutionary theory. Cambridge (MA): Schenkman Publishing Company; p. 19–49. Also reprinted under the same title. In: von BertalanffyLRapoportAMeierRL editors. 1969 General systems: yearbook of the society for general systems researchXIV. Society for General Research Systems; p. 69–85.