Eric Alden Smith: University of Washington Department of Anthropology

Collective action with low relatedness (large-n, low-r cooperation) is a common feature of human societies, in marked contrast to patterns in other species. This is particularly puzzling for small-scale societies of foragers and horticulturalists, where formal social institutions to enforce collective action are weak or absent. There is considerable disagreement regarding the evolutionary basis of such forms of collective action; some are convinced they can be explained via standard forms of mutualism, reciprocity, and coercion supplemented by reputation mechanisms, while others insist that various forms of cultural group selection are required. This debate has been protracted, and progress in our understanding of the issues appears stymied. I argue that progress can be made, but will require carefully targeted empirical evidence from naturalistic settings, particularly concerning the distribution of costs and benefits among collective action participants. I focus here on small-scale societies, and pinpoint areas in which empirical evidence could be particularly helpful. These include:

1) What are the payoff structures for empirically common forms of collective action?
2) How great is reproductive skew within groups, and what are its individual-level and institutional correlates?
3) At what frequency do groups with greater amounts of collective action prevail demographically?

I discuss ethnographic variation in Native North America to explore what patterns these phenomena might take. However, convincing answers to these questions will require carefully tailored analyses of new or existing data.
http://www.bec.ucla.edu/SmithPaper1.pdf