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.

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.

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.

Why did headhunting- the practice of taking human heads for ritualistic reasons- emerge in many societies? Through phylogenetic comparative analyses of Austronesian societies, the authors find that headhunting developed as a cultural response to frequent inter-tribal conflict and warfare. When warfare declined, the frequency of headhunting did as well.

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.