This study asserts that premastication (the pre-chewing of food for infant feeding) has existed as a cross cultural human universal stemming from the post natal immaturity of infant development and their need to have nutritional supplements to breast milk before they develop the molars necessary to consume an adult diet. Hypotheses are informally tested by sampling 119 cultures from the eHRAf database and looking for frequency of premastication occurrence. About one-third with information on infant feeding mention pre-mastication.

This book is a comparative study of the ways in which work is organized among non-industrial societies in the production of material goods. Two general hypotheses guide the author's work: (1) The structure of any work organization is influenced by both techonological processes and social setting, and (2) The structure of any reward system is influenced by the characteristics of the work organization, the social setting, and the limits imposed by features of the technological processes. Several predictions are presented and all are supported.

This study seeks to better understand different forms of leadership across non-WEIRD (Western, Educated, Industrialized, Rich, and Democratic) societies, and tests evolutionary theories regarding the qualities of leaders, their functions, and the costs and benefits they incur and provide as a part of their leadership. The authors assess the various aspects of leaders and leadership by coding 109 dimensions of leadership as represented in eHRAF World Cultures, using the Probability Sample Files, comprised on 60 cultures. By assessing the prevalence of each of these dimensions in the various cultures under consideration, the authors were able to ascertain some largely universal characteristics of leaders: that they 1) were judged intelligent and knowledgeable; 2) resolved conflicts; and 3) received material and social benefits. They also found that other dimensions varied by considerably group context (e.g., kin group leaders tended to be older), subsistence strategy (e.g., hunter-gatherer leaders tend to lack coercive authority), and gender (e.g., female leaders are more associated with family contexts). Further analyses showed that followers and leaders both benefited from leadership, and that shamans constitute a new brand of leader that both utilizes prestige and dominance in order to effectively rule.

The authors predict that fitness outcomes will be negatively associated with spousal relatedness among foragers but positively associated among non-foragers, due to the greater social benefits of intensive kinship systems among non-foragers. Support is found for this hypothesis; however, an interaction effect is discovered with inbreeding, which appears to account for the variability in these relationships independent of subsistence activity. The authors qualify this support in order to explain why the incidence of cousin-marriage in non-foraging societies is not higher.

An earlier study (Minturn & Lambert 1964) found a nonsignificant association between multifamily households and social permisiveness. This article re-tests that association using Barry et al.'s ratings for child socialization practices, finding that having several families in one house tends to decrease socialization pressure on children.

This chapter offers an exploratory study that examines the relationships between several culture characterstics, including child socialization practices, social structure, and food production, and mind-altering drug use in non-literate societies. All hypotheses were supported.

This paper examines relationships among mode of production, sedentarism, and population size. Generally, agricultural societies were found to be sedentary and have larger populations, while migratory societies (such as herders or hunters) had smaller population size.

"Data from 15 societies are presented in an effort to show substantial intersocietal differences of two types in susceptibility to geometric optical illusions. The results suggest the existence of different habits of perceptual inference which relate to cultural and ecological factors in the visual environment."

This study argues that different types of homosexuality must be examined separately. Authors focus on mentorship and pathic homosexual behavior and test factors that are associated with these two types of behavior.

This paper provides a linguistic study of the effect of lexical acculturation on the names given to days of the week. Findings show that loan words are used most frequently adopted for weekend days, followed by the days of the week that are closest to the weekends, and least frequently adopted for the days in the middle of the seven-day cycle.