Genetic, linguistic, and geographic data can be used to explain the distribution of cultural units ("semes") and to understand the evolutionary mechanisms of culture. Three broad models of cultural transmission attempt to explain why cultures share semes: (1) Cultural diffusion, emphasizing horizontal transmission. (2) Local adaptation, where trail-and-error learning leads to the independent adoption of semes by different peoples living in similar environments. (3) Demic diffusion, which emphasizes vertical and frequency-dependent transmission. Authors test the explanatory power of each model using cultural, genetic, linguistic and geographic data from 36 African cultures.

This study offers a preliminary exploration into the relationships between demography and childcare. Most of the hypotheses presented in this paper are are not formally tested, but are examined using previous research. These hypotheses should be used to inform future research. One hypothesis tested using limited data found that male biased sex ratios are likely to exist in societies where males contribute more calories to the diet than females.

This study evaluates recent research on the roles of fathers in child development in hunting-gathering, simple farming, and pastoral communities around the world. The authors review previously conducted studies as well as highlight the varying theoretical approaches that many of these previous studies have taken.

Considerable variation has been observed in allomaternal nursing (breast-feeding by individuals other than mothers) behavior across contemporary foraging populations: while relatively common in some populations, it is rare or absent among others. Here the authors examine data on allomaternal nursing from 12 previous studies of foraging societies and utilize a worldwide sample of 104 cultures to assess global variation in allomaternal nursing.

This article examines the homoarchical custom of hereditary community leadership. Four predictors are identified: (1) permission of premarital heterosexual intercourse by females, (2) small community population, (3) multiple social classes or castes, and (4) praying or violence as a component of community ceremonies. Log linear analysis shows all but the third are significantly associated with hereditary community leadership.

The focus of this article is the frequency of violent crimes. Five fomative experiences that are correlated with frequent violent crime by individuals are presented. This study uses the same sample as Ember and Ember (1992).

This article tests the general hypothesis that frequency of violent crimes by individuals is related to high concentrations of wealth.

This study focuses on variables associated with the subordination of community government. A detailed discussion of the specific relationships is presented.

This study presents a psychological theory for adolescent initiation ceremonies. Findings support the hypothesis that initiation is a mechanism for maintaining continuity between the stages of childhood and adulthood, when the body is physiologically in discontinuity.

This article discusses the relationship between child training and certain variables, such as economy.