The author analyzes 440 Sub-Saharan African societies to test whether trade across ecologically diverse zones is predictive of degree of state centralization (state capacity or strength of state) in pre-colonial Africa. The author finds that diverse ecology is predictive of state capacity and that trade supports class stratification. The author also emphasizes the importance of historical contingency and ethnographic data consultation in understanding mechanisms in individual cases.

Using a cross-cultural sample of 91 societies, this paper draws on ecological theory to test if unpredictable environments will favor subsistence diversification. The general hypothesis is that societies with high climate unpredictability and resource stress would exhibit more subsistence diversity than societies in more stable climates. The authors examined four environmental and resource stress variables while controlling for temperature variance, subsistence activity, and phylogeny. Support was found for 2 of the 4 variables--chronic scarcity and environmental instability. In the discussion they suggest that more commonly observed events (e.g. annual hunger and climate unpredictability) may give people more motivation to change subsistence than rarer events (e.g. natural hazards and famine).

Using a cross-cultural sample of 91 societies, this paper draws on ecological theory to test if unpredictable environments will favor subsistence diversification. The general hypothesis is that societies with high climate unpredictability and resource stress would exhibit more subsistence diversity than societies in more stable climates. The authors examined four environmental and resource stress variables while controlling for temperature variance, subsistence activity, and phylogeny. Support was found for 2 of the 4 variables--chronic scarcity and environmental instability. In the discussion they suggest that more commonly observed events (e.g. annual hunger and climate unpredictability) may give people more motivation to change subsistence than rarer events (e.g. natural hazards and famine).

Using a cross-cultural sample of 91 societies, this paper draws on ecological theory to test if unpredictable environments will favor subsistence diversification. The general hypothesis is that societies with high climate unpredictability and resource stress would exhibit more subsistence diversity than societies in more stable climates. The authors examined four environmental and resource stress variables while controlling for temperature variance, subsistence activity, and phylogeny. Support was found for 2 of the 4 variables--chronic scarcity and environmental instability. In the discussion they suggest that more commonly observed events (e.g. annual hunger and climate unpredictability) may give people more motivation to change subsistence than rarer events (e.g. natural hazards and famine).

Using a cross-cultural sample of 91 societies, this paper draws on ecological theory to test if unpredictable environments will favor subsistence diversification. The general hypothesis is that societies with high climate unpredictability and resource stress would exhibit more subsistence diversity than societies in more stable climates. The authors examined four environmental and resource stress variables while controlling for temperature variance, subsistence activity, and phylogeny. Support was found for 2 of the 4 variables--chronic scarcity and environmental instability. In the discussion they suggest that more commonly observed events (e.g. annual hunger and climate unpredictability) may give people more motivation to change subsistence than rarer events (e.g. natural hazards and famine).

In this study, the authors analyze subsistence economies to better understand their variability and success, the role of the environment in different subsistence choices, and the relevance of fishing, specifically in mixed economies. They find regular subsistence patterns, suggesting that not all subsistence combinations are successful. Their findings also indicate that environment influences subsistence choice, mixed economies are common, and that fishing plays a key role in mixed economies.

This article presents a representative theoretical model of the transition to agriculture. Empirical results from a cross-cultural sample provide support for the model. Results suggest that agriculture is associated with population density, technological sophistication, environment, and proximity to agricultural hearths, such as the Fertile Crescent.

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.

Prior research by Oswalt (1973, 1976) and Torrence (1983, 2001) has suggested that risk of resource failure is a significant predictor of toolkit complexity and diversity among hunter-gatherers. In this paper, the same relationship is tested among small-scale herding and farming groups. However, no significant correlation is discovered between any measure of resource risk and any measure of toolkit complexity. The researchers suggest that this absence may be the result of greater reliance on non-technological diversification methods among farmers (i.e. spatial diversification, mixed farming, intercropping), or of other unaccounted-for sources of risk (i.e. intergroup raiding and warfare).

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.