This article tests a series of hypotheses differentiating internal warfare and external warfare. Results support the theory that internal warfare is a population control mechanism more common in patrilocal societies, whereas external warfare occurs between two societies, one of which recently migrated and adopted matrilocal residence. Based on these findings, the authors assert that internal warfare can be regulated while external warfare cannot.

This article considers the consequences of modernization. Factor analysis is used to identify four stages of modernization: 1) changes in education, government, and trade; 2) changes in health, technology, and transportation; 3) changes in family, religion, and toilet; and 4) changes in behavior. The authors then consider five trends they expect to be associated with modernization and test whether they develop over the course of the four stages. Results indicate that these 5 trends—increased cultural complexity, female status, pacification, suicide, and social stress—are associated with only the first and fourth stages.

A model for the development of counting systems is tested. The hypothesis presented predicts that unpredictable climate conditions result in inconsistent food supply which leads to the need for food storage and, thus, a system to account for the stored food. Results strongly support this hypothesis.

This study explores possible causes of matrilocal residence. Previous hypotheses are unsupported. Results show a significant relationship between matrilocality and recent migration.

The association between hunting and sign language is examined. It is hypothesized that sign language develops as a form of nonverbal communication to aid hunters in the coordinated stalking of game. Ethnographic evidence supports this hypothesis. A second hypothesis is also tested concerning the relationship between population size and non-verbal communication, however sampling procedures provided an inadequate test of this hypothesis.

This study focuses on the factors associated with the development and persistence of an ideology of male supremacy. Authors identify several realms of culture that show a clear male preference and suggest that warfare is the most significant cause of the male supremacy complex in preindustrial societies. Authors hypothesize that warfare will be positively related to female infanticide. Results support this hypothesis. Another hypothesis relating diet to warfare and infanticide is provided, but not tested.

This article examines cultural forms of population control. Results suggest that female infanticide and warfare are interrelated and effective forms of population control.

This study builds on the work of Melvin Ember (1973) regarding living floor area of dwellings and its relationship to marital residence. The original results are replicated.

Several theories on the development of matrilocal residence are tested. The main argument put forth predicts that matrilocal residence will develop in response to a need to break up fraternal interest groups that encourage internal war and instead encourage a pattern of external war that is more beneficial in populated regions with additional group migration.

Considers the effect of data quality and gender of ethnographer on the relationship between female status and cultural complexity. Suggest that data quality controls clarify the nature of the relationship.