The social control hypothesis suggests that ritual human sacrifice may have played an important role in the evolution of social stratification, functioning to legitimize class-based power distinctions by pairing displays of ultimate authority with supernatural justifications. Authors test this hypothesis about human sacrifice with a phylogenetic analysis of 93 Austronesian cultures.

The present study examines 70 Austronesian cultures to test whether political hierarchy, population size, and social inequality have been influential in the conversion of populations to Christianity. Cultural isolation and year of missionary arrival are control variables. Using phylogenetic generalized least squares (PGLS), the researchers test the effect of the three predictor variables on conversion to Christianity and also conduct a multivariate analysis with all variables. The results do not offer support for what is expected by top-down and bottom-up theories of conversion but instead for the general dynamics of cultural transmission.

The researchers introduce the Pulotu database to readers, reviewing its function and role in future research. Researchers demonstrate the utility of the database by testing for headhunting cross-culturally. Findings include the presence of headhunting practices across proto-Austronesian cultures.

Researchers sampled 106 Austronesian societies from the Pulotu database to study the way political complexity evolves in relation to religious beliefs and practices. Specifically, they attempt to test the causal theory that supernatural punishment played a causal role in the emergence of large, complex societies. They use phylogenetic models to control for Galton's Problem in testing the supernatural punishment hypothesis in an effort to demonstrate the effectiveness of utilizing cross-cultural datasets in evaluating evolutionary change in human social organization.

Using data on 25 ethnolinguistic groups in the Austronesian language family, this study asks: does cooperation in games vary with socio-ecological differences across cultural groups? The authors suggest that cultural groups that cooperate in subsistence, tend to have intergroup conflict and less intragroup conflict, and are less socially stratified are more likely to play cooperative games compared to other groups. While the results support the first three hypotheses, there is insufficient data to support the fourth. The authors conclude that games serve as training ground for group norms and values.

Research sampled 143 societies from the Standard Cross Cultural Sample to test the relationship between honor culture, social rewards for warriors, and intergroup conflicts. Using mediation analysis based on multiple regression, and structural equation modeling, the research supported the theory that honor culture was positively associated with intergroup conflict, and that this relationship was mediated by social rewards for warriors.

This article offers an exploratory study of the fitness costs of warfare on women. The author examines stories of inter-group conflict cross-culturally and finds that warfare exerts significant selection pressure on women, such as killing or capturing women, or killing their offspring or mate. The author suggests that future research should examine female cognition in relation to these selective pressures.

This article examines resource problems and warfare in a sample of societies from eastern Africa. The frequency and predictability of resource problems are examined, as are two other dimensions of warfare: resource-taking and commission of atrocities. Differences between state and nonstate societies, as well as pacified and non-pacified societies, are also examined and shown to affect associations between resource and warfare variables.

This book investigates the evolution of military organizations and their activities. Hypotheses frequently relate military organizations to political variables. Data suggested that more politically centralized societies have more sophisticated military organizations which are more likely to be successful in conflict (though military sophistication does not appear to deter attack).

In this article, the authors explore cultural variables that they propose contribute to the maintenance of peace in non-warring societies. These variables are compared in 16 peaceful systems (as coded by the authors from anthropological and historical data) and in 30 warring societies taken from the Standard Cross-Cultural Sample (SCCS). Findings associate more peaceful cultures with peace systems, and non-peaceful cultures with warring societies.