This article explores differences between "tight" cultures ("have many strong norms and low tolerance of deviant behavior") and "loose" cultures ("have weak social norms and high tolerance of deviant behavior"). The tightness-looseness measure manifests in a myriad of macro and micro phenomena, from governance and religiosity to individual psychological processes. This study investigates these phenomena in modern nations rather than traditional societies. Potential ecological, historical, and socio-political predictors of tightness-looseness are also examined.

This article examines the relationship between the tightness-looseness of a culture and the variation of COVID-19 cases and deaths through October 2020. With COVID-19 data retrieved from Our World in Data from 57 countries with tightness-looseness figures, the article found the cultures with high levels of tightness had fewer COVID-19 cases and deaths when compared to countries with high levels of looseness. Results suggest support of the evolutionary game theoretic model proposing that people in tight cultures may cooperate with more urgency when under collective threat than people in loose cultures.

This article tests differing theories of why a man's marriage of his mother's brother's daughter is often encouraged while marriage of the father's sister's daughter is discouraged. Maintenance of relationships between bride-givers and bride takers is considered, as are the role of childhood sentiments in choosing a spouse.

In this study of 80 societies, the author initially sets out to test the theory that if social customs and rules forbid satisfaction of sexual impulses, "civilization" will be built based on sacrifices of these desires.

This article tests the effect of environmental risk on parental investment, differentiating between maternal and paternal care. Results indicate that the saturation point of parental investment may be a function of environmental risk, as parental care experiences diminishing returns due to extrinsic risks.

This study examines the relationship between pairbonds and lactation, specifically the relationship between pairbond stability, alloparenting, and cross-cultural trends in breastfeeding. Findings show that both conjugal stability and availability of alloparental care are associated with age at weaning.

This study employs a psychological theory and builds on the holocultural literature on male homosexuality. Two hypotheses relating homosexual behavior among men to social constructs for sexuality (the couvade, male transvestism) are derived from a study by Munroe (1980). The hypotheses are tested and supported in a sample of cultures drawn from Munroe's codes and the Human Relations Area Files.

This article examines the results of a study (Gaulin 1980) on male parental certainty and subsistence type. Methodological errors are assessed and the hypotheses are retested.

Drawing on various theories regarding the sexual division of labor, Broude examines the relationship between task differentiation by sex and gender-related behaviors/customs.

A study of the factors that predict extremely masculine behaviors and traits in men (conceptualized as protest masculinity in the status-envy and father-absence theories). Findings point to the important role of socialization for aggression as a mediating factor in the relationship between father's role and "protest masculinity."