Cultural multi-level selection and biological market theory explain the coupled dynamics of labor exchange cooperation and social support

Abstract

Smallholders rely on labor exchange and social support networks; however, little is known about the cooperative dynamics of these interlinked systems. Whereas cultural multi-level selection (CLMS) predicts group membership and changes in the dominant level of selection modulates cooperation, biological market theory (BMT) posits market size fluctuations affect cooperation. We assess these predictions by examining two dimensions of labor exchange, competitive helping and labor reciprocity, and their downstream impacts on social support in a Dominican community between 2007 and 2010. First, we analyze within-community labor organization. Next, we analyze how international regulatory change and the 2008–2009 World Trade Collapse affected local labor organization and its impacts on competitive helping and labor reciprocity. Finally, we show how labor dynamics affected social support. Analyses reveal that (1) village labor initially involved two levels (labor contracting and labor exchange) and the presence of a structured group who maintained higher rates of reciprocal labor relative to non-group members; (2) changes in the international commodities market reduced labor contracting, the size of the labor exchange market, and the dominant level of selection, resulting in less competitive helping, lower rates of reciprocity for group members, and more cliquish social support; and (3) as the global market for bay oil ameliorated, labor organization shifted back to a pre-recession structure, resulting in a larger labor market with more competitive helping and higher rates of reciprocity amongst group members. We highlight the utility of an integrated CMLS and BMT framework for analyzing cooperative dynamics and socio-economic systems sustainability.