What causes people to trust or distrust others? Through a multi-level empirical analysis, the authors of this article find that societies with historical exposure to infectious diseases will tend to minimize contact with contaminated out-groups while strengthening in-group relationships to manage infections, thus developing a lower radius of trust.

This article examines possible environmental predictors of ethnic diversity around the world. Results suggest that global ethnic diversity is associated with latitude, habitat diversity, pathogen stress, and climate.

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 retests the work by Ember, Ember and Low (2007) on male mortality and pathogen stress as predictors of nonsororal polygyny. The authors argue that the work of Ember, Ember, and Low is biased because it does not include a variable for cultural trait transmission. Restesting the original Ember, Ember and Low data, including a variable for cultural trait transmission, authors find that male mortality and pathogen stress loose their significance and cultural trait transmission is the only significant predictor of nonsororal polygyny.

This article builds on previous cross-country and cross-state research into Tightness-Looseness (TL) theory, which proposes relationships between the incidence of ecological threat and cultural tightness, as well as tightness’ downstream effects on belief in a moralizing high god, inter-group contact and authoritarian leadership. To evaluate the generalizability of TL theory beyond complex cultures, the authors test these relationships among 86 nonindustrial societies from the ethnographic record. A structural equation model is presented of the results for nonindustrial societies; it is generally in accord with previous findings from more complex societies. Because the nonindustrial sample is more variable, they also look at relationships between societal complexity and kinship heterogeneity, aspects that vary in nonindustrial societies.

The authors contribute to a growing body of theory which posits cultural differences as a result of variable pathogen prevalence by testing the relationship between pathogen richness and various measures of conformity in a cross-regional sample. After controlling for confounds such as life expectancy, GDP, population density, arable land area, and agricultural labor force, the authors suggest that conformity is emphasized to varying degrees in response to the increased vulnerability to pathogens generally associated with deviation from normative social conduct.

Researchers used population samples from the ALFRED database and the Human Genome Diversity Project (HGDP), in conjunction with 68 populations from the Ethnographic Atlas, in an attempt to identify specific genes involved in human adaptation to environmental stimuli as a result of migration. Specifically, researchers looked at the allele frequencies for four different genes typically associated with varying subsistence forms. These four included the APOE apolipoprotein E gene (lipid transport and regulation of cholesterol), LCT lactase gene (enzyme that decomposes lactose), CCR5 chemokine receptor gene (deletion mutation that decreases immunodeficiency virus propagation), and the ADH1B alcohol dehydrogenase gene (important enzyme for alcohol metabolism). The allele frequencies were then analyzed to distinguish any possible correlation to economic-culture types using a two-sided Spearman Test. Researchers also ran a similar test to analyze allele frequencies and pathogen load, however the majority of the findings were not statistically significant. The findings suggest that there is a definite relationship between the allele frequencies and type of economy of a population.

This article employs cross-national and cross-cultural methods to investigate whether pathogen stress is a direct determinant of authoritarianism. The study controls on other factors such as famine, warfare, and malnutrition and evaluates alternative causal models.

This study examines the relationship between body scarification and pathogen prevalence. Authors hypothesize that risk of serious pathogens will be related to scarification on areas of the body that are associated with physical attractiveness and fertility. Results show that only female stomach scarification is significantly related to pathogen prevalence.

This article focuses on the effect of environmental extremes and unpredictability on human behavior and reproductive strategies. Significant correlations were found between environmental extremes and unpredictability and several variables, including mobility, subsistence mode, and degree of polygyny.