The unit of replication in socio-cultural evolution

Abstract

The last two decades have witnessed a sustained renewal of interest in the application of Darwinian evolutionary theory in the social sciences, most notably to the historical development of culture. Sociobiology has provided a powerful impetus to this trend, but contributions have also come from a variety of other disciplines (Campbell 1965; 1975). The common basis for such interest lies in recognition of the need to situate the evolution of man, including the evolution of human behavior and culture, firmly within an overall biological context, while avoiding the pitfalls of earlier attempts, e.g. those of Spencer (1972 [1873]). To this end a number of hypotheses have been advanced extending the twin Darwinian principles of variation and selective retention to provide the common theoretical basis necessary for both biological and sociocultural evolution to be subsumed within a common evolutionary theory. Notable contributions to a Darwinian theory of sociocultural evolution have come from Campbell (1965) Hill (1971), Ruyle (1973) Cloak (1975), Richerson and Boyd (1978), Durham (1979; 1982), Mundinger (1980), Pulliam and Dunford (I 980) Plotkin and Odling-Smee (198 I), Cavalli-Sforza and Feldman (198 I), and Lumsden and Wilson (I 98 I). While these various theories differ in the extent to which they envisage biogenetic and sociocultural evolution interacting in the development of human societies and cultures, all agree on the essential mechanism by which the evolution of culture must proceed: selective retention of a variable ‘unit of culture’. By analogy with the gene in biogenetic evolution, some ‘unit of culture’ is taken to be the elemental means by which culture is both replicated and transmitted. Such a unit must be able to be transmitted and be open to variation (mutation). Therefore, in the final analysis, it must be particulate. But while these properties have been widely recognized, there has been little or no agreement on just what constitutes a ‘unit of culture’. Numerous suggestions have been made ‘traits’, symbols, ideas, concepts, ‘memes’, ‘culturgens’, etc. but none has found general acceptance. Indeed in a recent assessment of current theories of sociocultural evolution. Daly states flatly that there is still no cultural analogue for the gene (Daly, 1982: 402). The identification of the unit of replication in sociocultural evolution is not simply of importance for its own sake: on it depends any real progress in developing either an evolutionary theory of social change, or a coevolutionary theory linking biogenetic and sociocultural evolution. What Bronowski stated in 1977 still holds true, despite advances since then: ‘we do not know the mechanism for social change because we have not been