This article investigates incest rules, proposing that they are instituted by rulers as a way of preventing wealth-concentration among non-ruling families. Three hypotheses are derived and supported with empirical analysis. Two alternative evolutionary hypotheses are discussed and dismissed by the author.

This article investigates incest rules, proposing that they are instituted by rulers as a way of preventing wealth-concentration among non-ruling families. Three hypotheses are derived and supported with empirical analysis. Two alternative evolutionary hypotheses are discussed and dismissed by the author.

This article investigates incest rules, proposing that they are instituted by rulers as a way of preventing wealth-concentration among non-ruling families. Three hypotheses are derived and supported with empirical analysis. Two alternative evolutionary hypotheses are discussed and dismissed by the author.

This article tests the effect of environmental risk on parental investment, differentiating between maternal and paternal care. Results indicate that the saturation point of parental investment may be a function of environmental risk, as parental care experiences diminishing returns due to extrinsic risks.

This article tests the effect of environmental risk on parental investment, differentiating between maternal and paternal care. Results indicate that the saturation point of parental investment may be a function of environmental risk, as parental care experiences diminishing returns due to extrinsic risks.

This article tests hypotheses related to kinship terms, cousin marriage, and descent rules. Omaha, Crow, Eskimo, and Iroquois systems are each significantly associated with different kinship rules. Material from Northern Ghana is also considered.

This article tests hypotheses related to kinship terms, cousin marriage, and descent rules. Omaha, Crow, Eskimo, and Iroquois systems are each significantly associated with different kinship rules. Material from Northern Ghana is also considered.

This article presents tests of hypotheses derived from an evolutionary approach to the rape of women. A cross-cultural test of the relationship between polygyny and rape in non-industrial societies is presented. Results suggest that the degree of polygyny is positively associated with the severity of punishment for rape.

Researchers examine marriage patterns of 186 societies from the Standard Cross-Cultural Sample (SCCS). The eleven predictor variables are pathogen stress, arranged female marriages, population density, father roles during infancy, temperature, social stratification, wealth inequality, internal warfare, assault frequency, female agricultural contribution, and sex ratio. The two outcome variables measuring polygyny are cultural rules constraining polygyny and the percentage of married men who are polygynous. Controlling on phylogeny using a global supertree of the languages, analysis of marriage patterns reveals that assault frequency and pathogen stress are the strongest predictors of polygyny. These findings offer additional support for the theories of harem-defense polygyny and male genetic quality.

The authors investigate environmental reasons for cross-cultural variation in the permissibility of cousin marriages. In particular, they test whether higher levels of pathogen prevalence and geographic isolation increase the likelihood that cousin marriage will be allowed. The authors' underlying theory is that cousin marriages provide protective homozygosity against some pathogens and provide more options when mate choices are limited.