This study develops a model of the conditions under which a societies switch from a anarchy to a hierarchy. Empirical results suggest that the presence of police, technological sophistication, population density, and food storage are positively associated with the presence of a territorial hierarchy.

This study examines land ownership and territoriality among hunter-gatherers in relation to resource density and predictability and defense technology. A model is presented and briefly tested on a cross-cultural sample of 14 hunter-gatherer societies. Results suggest that societies in more resource-rich areas will be more territorial than societies in less resource-rich areas.

This study presents a theory of land inheritance that "focuses on the incentives that land inheritence rules create for potential heirs" and tests this theory on a cross-cultural sample.

Belief in moralizing high gods (MHGs) has been theorized as a response to unfavorable environments, as a way to normalize behavior. In this study, researchers test the theory by creating a model for predicting the distribution of MHGs. They run many alternative models, testing the effects of resource abundance, climate stability, and pertinent social factors on the occurrence of belief in MHGs. Based on the ten most supported models, they create an average model that predicts MHGs within cultures with “excellent” accuracy.

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.

Researchers investigated the variation of land tenure systems across forager societies using the economic defensibility model. The study attempted to explain the variation in tenure systems across 30 hunter-gatherer societies. Using data on defense and sharing of resources among groups, and indicators of resource density, resource predictability, and competition for resources, the researchers were unable to explain the variation. This study highlights the vast range of diversity and complexity of foragers subsistence strategies, and proposes that it may be more telling to conceptualize tenure systems among hunter-gatherer societies as assemblages of multiple property regimes. While there was no overall evidence that environmental variables of resource density and predictability explain variation in tenure systems, researchers did find that increasing population density, and greater competition for resources leads to greater territoriality.

This article uses factor analysis to identify the key variables underlying the many cross-cultural associations reported by Textor (1967). Twelve factors are identified.

Using t-test, generalized linear models (GLMs) and Bayesian regression models in a sample of 1188 pre-industrial societies, this study explores the research question: Why have foraging, horticulture, and pastoralism persisted into the 20th and 21st century? The authors test the marginal hypothesis and the oasis hypothesis of agricultural intensification. The first hypothesis suggests that foragers persisted because foragers predominantly inhabited marginal habitats that were typically unsuitable for agricultural purposes. The second hypothesis suggests that intensive agriculture emerged in regions characterized by limited biodiversity and a dependable water supply not reliant on local rainfall. In addition, the authors test whether specific kinds of biodiversity (elephants, malaria, and tsetse flies) correlate with agricultural intensification in African societies. The results support the marginal and oasis hypotheses, but only marginally support the African hypothesis, since only tsetse fly has a significant negative correlation to agricultural intensification.

This article investigates the adoption of agriculture. The author tests three possible predictors: environmental richness, population density, and division of labor by gender. Minimal support is found for these variables, and the author proposes two alternative explanations, based on diminishing returns in food production and balancing the food portfolio.

Inter-group variation is greater in humans than in any other animal, and scholars continue to debate the cause of this diversity. Two competing explanatory models of human variation emphasize either (1) ecological differences and "evoked" culture or (2) population-level effects of cultural transmission. The former emphasizes mechanisms that operate within a single generation, while the latter emphasizes cumulative cultural history operating over many generations. To test these competing models, the authors measured the relative power of ecological variables as compared to culture history to predict behavioral variation in 172 western North American tribes. Culture history is subdivided into culture phylogeny (based on language phylogeny) and spatial distance.