Paddy rice, aggregation, and the development of Mumun social organization in Ulsan, southeastern Korea

Previous research has reported that Mumun settlements (ca. 1500–300 BCE) in southeastern Korea consisted of multiple house clusters that were basal social units. This study evaluates this claim by inspecting intra-settlement dwelling distribution in sites with more than 40 pithouses. Ripley's K-function and the density-based spatial clustering of applications with noise (DBSCAN) method were implemented to identify pithouse clusters at different spatial scales. Our examination shows that the settlements contained small, primary clusters of ca. 10–40 people, which merged into larger, secondary clusters of fewer than 60 people. Large settlements consisted of multiple secondary clusters. We infer that people aggregated to meet the labor demand of paddy rice cultivation, while simultaneously managing the scalar stress by dividing communities into smaller subgroups. This study suggests that emergent social complexity during the Mumun period relied on factional competition and cooperation and was dependent on the effective integration of discrete social units.