If you ask someone to divide a pie between two imaginary recipients, they are likely to recommend a 50/50 split. Philosophers like Brian Skyrms and Jason Alexander have employed evolutionary game theory to explain why such “fair” divisions are almost universally observed in experimental work, and to explain the ubiquity of stated norms of fairness in human societies. When one moves away from an idealized lab setting, however, resource division is rarely governed by these stated norms. In this talk, Cailin O’Connor will use evolutionary game theory to show why unequal patterns of division often emerge between social groups.