This article draws from anthropology, psychology, and history to gain insight into the causes of large-scale psychological variation among humans. The authors of this study are mainly concerned with the way that weak kinship structures induced by policies of the Western Church in Europe may have resulted in the modern "WEIRD" (an acronym for "Western, Educated, Industrialized, Rich, and Democratic") psychological profiles in that same region. By correlating the amount of contact with the Western Church, rates of cross-cousin marriage (as an element of kin tightness), and degrees of individualism (as an element of WEIRD psychology), the authors are able to find support for this theory.

This article draws from anthropology, psychology, and history to gain insight into the causes of large-scale psychological variation among humans. The authors of this study are mainly concerned with the way that weak kinship structures induced by policies of the Western Church in Europe may have resulted in the modern "WEIRD" (an acronym for "Western, Educated, Industrialized, Rich, and Democratic") psychological profiles in that same region. By correlating the amount of contact with the Western Church, rates of cross-cousin marriage (as an element of kin tightness), and degrees of individualism (as an element of WEIRD psychology), the authors are able to find support for this theory.

In this paper, the author argues that moral systems evolved as a way to enforce cooperation between people outside of kin groups. Because cooperation within kin groups has apparent adaptive advantages, it is argued that these moral systems will be less important for societies with tight kin groups and conversely more important for those with looser kin groups. In order to test this theory, the author creates an original model that incorporates both ethnographic data and data from contemporary countries. Thus, it is postulated that historical kinship practices will influence contemporary systems. The paper concludes that there is sufficient historical evidence for this theory.

In this paper, the author argues that moral systems evolved as a way to enforce cooperation between people outside of kin groups. Because cooperation within kin groups has apparent adaptive advantages, it is argued that these moral systems will be less important for societies with tight kin groups and conversely more important for those with looser kin groups. In order to test this theory, the author creates an original model that incorporates both ethnographic data and data from contemporary countries. Thus, it is postulated that historical kinship practices will influence contemporary systems. The paper concludes that there is sufficient historical evidence for this theory.

In this study, the authors inspect the relationship between religion, morality, and cooperation by examining the extent to which people associate their deities with moral concern. Using data from 2,228 individuals in 15 different field sites, they find that on average, people tend to ascribe at least some moral concern to their deities, and this effect is stable even after controlling for the influence of explicitly moralistic deities that these societies also worship. The authors also find that ratings of moral concern are not necessarily very high, even for deities that are typically considered to be moralistic, and that there is individual-level variation in the degree of moral concern attributed to deities. In addition, there is an individual-level correlation between how morally interested two selected deities are conceived to be and that being male or more educated decreases the likelihood of associating deities with moral concern. These findings challenge the longstanding belief that belief in moralistic deities is unique to certain societies or religions and instead suggest that the association between deities and moral concern is more widespread and variable, and suggest that the moral character of gods may be tied to cooperation within societies.

Researchers used various hypotheses to determine if cross-country differences in trust and cooperation would predict prosocial COVID-19 responses and policies. Using individual surveys from 34,526 participants from 41 countries, there were no significant associations between trust and cooperation and prosocial behavior, motivation, regulation, or stringency of policies. While the researchers did find significant variation among cross-country individuals, these results were unable to predict country-level prosocial responses.

Drawing from previous theories on the cultural variation of depression, this article tested the relationship between 24 sociocultural and ecological factors and the prevalence of depression across 195 countries and territories. The authors first conducted a zero-order association test to find the most contributory factors. Those variables were further tested in a regression model, and controlled for the under-reporting of depression by measuring the number of healthcare workers per capita. The authors found that cultural individualism was the only factor that positively predicted depression prevalence in a multiple regression model.

Drawing from previous theories on the cultural variation of depression, this article tested the relationship between 24 sociocultural and ecological factors and the prevalence of depression across 195 countries and territories. The authors first conducted a zero-order association test to find the most contributory factors. Those variables were further tested in a regression model, and controlled for the under-reporting of depression by measuring the number of healthcare workers per capita. The authors found that cultural individualism was the only factor that positively predicted depression prevalence in a multiple regression model.

The authors investigate environmental reasons for cross-cultural variation in the permissibility of cousin marriages. In particular, they test whether higher levels of pathogen prevalence and geographic isolation increase the likelihood that cousin marriage will be allowed. The authors' underlying theory is that cousin marriages provide protective homozygosity against some pathogens and provide more options when mate choices are limited.

The authors investigate environmental reasons for cross-cultural variation in the permissibility of cousin marriages. In particular, they test whether higher levels of pathogen prevalence and geographic isolation increase the likelihood that cousin marriage will be allowed. The authors' underlying theory is that cousin marriages provide protective homozygosity against some pathogens and provide more options when mate choices are limited.