Humans differ from other animals in their great capacity to learn from each other. Recently, theories of cultural evolution have come to provide some insights to many important questions in social sciences, such as cultural variation, cooperation, social learning, and decision-making under uncertainty. Different social science disciplines are currently addressing these questions with divergent vocabularies and methodologies. Cultural evolution models and evolutionary theories in general have the potential to bridge disciplinary divides. Unfortunately, theories of cultural evolution have received little empirical testing in either field or experimental studies. This project will conduct a series of micro-society experiments to test the behavioral implications of theoretical models of cultural evolution. Micro-societies are groups of interacting human participants who receive variable amounts of money based on how they perform over multiple time periods in an experimental task. Laboratory micro-societies are an attractive method because individual and population-level behavior can evolve and produce interesting emergent patterns over time. The researchers will simulate critical features of evolutionary models by controlling the structure of the experimental task and the kinds of information available to participants. They will develop a series of traditional and computer-mediated laboratory experiments, as well as Internet-based experiments that can tap into a global pool of subjects from diverse backgrounds and cultures, to test success-biased social learning strategies where people use the payoffs of others to guide their own decision-making. Theories of how people use the success of others to acquire their own behavior are common in the social sciences, but empirical tests and refinement of these theories is very uncommon. Thus this work will be of general importance to many fields concerned with the details of how people make decisions in social environments. The project will use maximum likelihood techniques to estimate how much participants rely on individual versus social learning under different experimental conditions. The broader impact of the research relates to the value of new knowledge about the evolution of patterns of cooperation, institutions, and cultural norms and symbols. The research will help reveal the basic behavioral mechanisms that underlie these processes, and therefore will be useful to policy makers concerned with large-scale social changes that have profound implications for human welfare.
