This article focuses on the effect of environmental extremes and unpredictability on human behavior and reproductive strategies. Significant correlations were found between environmental extremes and unpredictability and several variables, including mobility, subsistence mode, and degree of polygyny.

Focusing on 61 preindustrial societies that have information on fertility, the author asks what factors may explain variation in fertility, what devices are used to control fertility, and whether differences in fertility appear to be in line with the societies' environments.

This article focuses on ecological correlates of sexual division in the control of resources. The author tests several ecological theories put forth by others. Sex coalitions are examined in humans, and sexual dimorphism in resource acquisition and control is discussed.

Based on prior findings, the present study tests the theory that subsistence type, specifically agricultural level, influences descent type, conjugal formation, and marriage type. All three of the latter variables are predicted to be antecedents of ancestor worship. The author claims support for the theory.

This article discusses the variation in sex ratios at birth among human populations and the possible explanations for this variation. One possible explanation is the timing of intercourse and its relationship to the frequency of intercourse, which can affect the timing of conception. The article presents evidence that the male/female sex ratios of 148 countries declined with total fertility rates and polygyny intensity and increased with contraception use in correlational analysis. These results were independent of mother's age and level of economic development. The predictive effect of polygyny and contraception disappeared when total fertility was added to the equation. The article also considers other possible explanations for the variation in sex ratios, such as genetics, hormones, nutrition, and social factors.

The goal of the paper is to demonstrate how international slave trade spread the institution of slavery throughout Africa, resulting in long-term effects of the continent’s income and political centralization. The author first estimated the travel time to slave ports from each society in the Ethnographic Atlas to determine predicting factors for the adoption of slave trade in African societies. The author reported that societies with high exposure to slave capture in the past were more likely to have the custom of slavery and the custom of polygyny. The author further suggested that slavery institutions emerged in West Africa through local, politically centralized aristocratic systems while emerging in East Africa through the preservation of wealth within the nuclear family over generations.

Based on prior findings, the present study tests the theory that subsistence type, specifically agricultural level, influences descent type, conjugal formation, and marriage type. All three of the latter variables are predicted to be antecedents of ancestor worship. The author claims support for the theory.

This article focuses on ecological correlates of sexual division in the control of resources. The author tests several ecological theories put forth by others. Sex coalitions are examined in humans, and sexual dimorphism in resource acquisition and control is discussed.

The present research inquires into the effects, if any, that male status and power have on extramarital sex, parental investment, and polygyny. Using sexual selection theory, the hypothesis is that males in higher positions of power and status are more likely to engage in extramarital sexual activities and be in polygynous relationships was supported. There was no support for an association between male extramarital sex and parental investment.

The purpose of this article is to examine circumcision and segregation of males at puberty. It is suggested that when the son has insufficient contact with his father due to the separation caused by polygynous relationships, the son may develop a feminine personality. The significance of this is compared with the significance of a close mother-son relationship.