This study investigates the relationship between societal complexity and familial complexity. Results suggest that the relationship is somewhat curvilinear; that is, in simpler societies more societal complexity is associated with a larger familial system, but the most developed societies have smaller familial systems. The demographic, economic, and politcal correlates of maximum family size are discussed.

In this study, the authors examine pathways to social inequality, specifically social class hierarchy, in 408 non-industrial societies. In a path model, they find social class hierarchy to be directly associated with increased population size, intensive agriculture and large animal husbandry, real property inheritance (unigeniture) and hereditary political succession, with an overall R-squared of 0.45. They conclude that a complex web of effects consisting of environmental variables, mediated by resource intensification, wealth transmission variables, and population size all shape social inequality.

This study tests the relationship between population pressure and social evolution in agricultural societies. The author predicts that population pressure will be positively related to the evolution of descent, political integration, and class stratification. Results support this prediction.

The second and third parts of this book classify the economic systems of foraging and agricultural societies in the SCCS based on correlations between their institutions of property an distribution. These economic types are then examined for relationships with other social, political, demographic, and environmental factors in order to draw tentative conclusions regarding the origins of the Agricultural and Industrial Revolutions. The fourth part of the book uses cross-national data to examine similar associations in industrial/service economies, and is not included here.

This study examines why conflict emerges and how societies resolve it. The authors posit that increasing societal scale and differentiation create more potential for conflict but also more complex forms of conflict resolution. Analysis supports this theory, showing that measures of cultural complexity are positively associated with legal mechanisms for conflict resolution.

The authors develop and empirically test a model in which exogamy is negatively predicted by community size, due to decreasing heterogeneity from endogenous marriages in small settlements, and positively predicted by disparity in productivity between communities which is 'smoothed out' by transfer of community members through exogamous marriages. Support for both predictions is found, which is used to argue that cultural traits like marriage customs are heavily influenced by population-environment relationships.

The authors develop and empirically test a model in which exogamy is negatively predicted by community size, due to decreasing heterogeneity from endogenous marriages in small settlements, and positively predicted by disparity in productivity between communities which is 'smoothed out' by transfer of community members through exogamous marriages. Support for both predictions is found, which is used to argue that cultural traits like marriage customs are heavily influenced by population-environment relationships.

Expanding on the author’s previous findings, this article examines the social and economic variables that may explain the cultural evolution of religious practitioners. With a 47 society sample, the author found that subsistence activities and socio-political conditions predict magico-religious practitioner types (sorcerers/witches, priests, shamanistic healers, mediums, healers, shaman/healers, and shamans) with the strongest results being from subsistence and political organization. He then used these findings to theorize about the biogenetic bases of religion in societies.

Focusing on cultures of New Guinea, this article tests the relationship between subsistence type and various indicators of cultural complexity: population density, settlement size, and residential permanency. Subsistence type is examined through dependence on aquatic resources--specifically, the consumption of aquatic fauna. Relevance of social and political history of the region is also examined.

Researchers tested four models of leadership for qualities and correlates that could predict the transmission of leadership cross-culturally. Researchers sampled 60 societies from the Probability Sample Files, coding for 24 variables. Support was found for the prevalence of the collective action model and the prestige model, with a lack of support found for the dominance leadership model.