A macroecological theory of social complexity

How are scale and complexity related in human societies? To answer this long-standing question, we develop a theoretical model of polities as territorial social networks that are functionally integrated by institutions. Our model hypothesizes how agricultural intensity, territorial area, and social complexity are related and how they scale relative to population size. We test the model's predictions using data from "Seshat: Global Databank" which describe hundreds of polities worldwide from across the Holocene. We find that intensity, territory, and complexity scale with population size as predicted. Our results provide evidence in support of theories of social complexity that emphasize its role in fostering large-scale cooperation.