Geophagy during pregnancy has been proposed to fulfill a number of adaptive functions, including relieving gastrointestinal distress, detoxification of the secondary compounds found in plant foods, and providing a supplementary source of minerals such as calcium. Using a sample of 60 African populations, the authors investigate geophagy during pregnancy in a cross-cultural perspective, emphasizing variation between dairying and non-dairying populations.

One of the core psychological concepts of early childhood development is mother-infant attachment, an infant's drive to form a bond with one caretaker. John Bowlby identified this form of attachment as a fundamental evolved adaptation, with alternative forms of "insecure" attachment being deviations from the healthy developmental trajectory. In contrast, life-history theory emphasizes that alternative developmental trajectories can be thought of as adaptive strategies which match phenotypes to local conditions, and thus variation in infant attachment may be adaptive under different environmental conditions. Here the authors attempt to investigate whether variation in fertility and mortality rates are significant predictors of variation in infant attachment. However, they do not find enough variation to test their hypotheses since very few societies in the HRAF sample exhibit both low fertility and low mortality.

By better understanding the factors influencing adult height in modern populations, the authors hope to generate a testable hypothesis to determine the factors affecting body size during hominin evolution. The authors employ an exploratory linear regression model to test the effects of mortality, environment, and subsistence strategy on adult height among traditional small scale human societies. They found that mortality rates were the most significant predictor of adult height and that people living in savanna environments are consistently taller.

The 'obstetrical dilemma' postulates that human females evolved a pelvis shape that was a compromise between the needs of bipedal locomotion and the need for a wider pelvic opening. The implication is that the female pelvis should be similar across the world. Researchers examine the size and shape of the birth canal of female individuals in the Goldman and Human Origin datasets. Contrary to the 'obstetrical dilemma,' the findings reveal that there is indeed significant geographical variation in size and shape of the female birth canal. Neutral evolutionary processes, particularly genetic drift, were suggested to be influential in female canal shape whereas the predicted effects of climate on canal diversity were only minimal.

This study explores predictors of variation in two dimensions of marital residence patterns among hunter-gatherers: 1) the tendency toward patrilocality versus matrilocality and 2) the tendency toward unilocality versus bilocality.

The present research investigates food sharing and labor sharing practices of 98 nonindustrial societies. The aims are to: 1) document the frequency and scope of sharing, and 2) test the theory that greater sharing is adaptive in societies subject to more resource stress (including natural hazards).

This article uses the Standard Cross-Cultural Samples to test the relationship between disease and economic growth among sub-Saharan African societies. The authors suggest that a higher disease prevalence limits social integration and economic development since pre-colonial times. The variable measuring economic growth is the complexity of large or impressive structures. The hypotheses are that 1) pathogen stress is negatively correlated to the presence of complex buildings, and 2) pathogen stress is positively correlated to increased ethnic diversity. The results support both hypotheses, and there are additional results, like 1) the negative correlation between pathogen stress and current income per capita and 2) the negative correlation between the increased ethnic diversity and current income per capita. Overall, this article shows the robust relationship between disease and economic development.

This study relates the type of games present in a society to the level of cultural complexity. Authors use a "game-type combination scale" that categorizes societies as having: 1) games of physical skill only; 2) games of physical skill and games of chance; and 3) games of physical skill, games of chance, and games of strategy. Results show a relationship between the game-type combination scale and indicators of cultural complexity.

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.

This article investigates a cultural patterning of altered states of consciousness. The authors use an ordinal variable for a society's trance type; its four levels are 1) trance, 2) trance and possession trance, 3) possession trance, and 4) neither type. Results suggest that trance type is associated with measures of societal complexity and subsistence economy. Regional differences and the effects of diffusion are also examined.