The researchers develop and compare two evolutionary models to evaluate the association between social stratification and female genital modification(FGMo) in a cross-cultural African sample, theorizing that social hierarchy creates competition for high-value males in which FGMo acts as a costly demonstration of paternity certainty. Although the null model outperforms the stratification model when applied to empirical data, an association between FGMo and stratification is found in the expected direction. The authors suggest that while stratification may be an important factor in the de novo origins of FGMo, spread and persistence of the practice subsequently become more heavily dependent on other selective forces.

This study is a comprehensive analysis of female and male genital mutilation/cutting (FGM/C and MGM/C) practices, including their history and socio-ecological correlates, using a phylogenetic cross-cultural framework. It employed two global ethnographic samples, the Ethnographic Atlas (EA) and the Standard Cross-Cultural Sample (SCCS), and two subsets of the phylogeny (supertree) of human populations based on genetic and linguistic data, to investigate the variables that may have led to the introduction of these practices, and to determine where and when they may have originated. The study suggests that MGM/C probably originated in polygynous societies with separate residence for co-wives, supporting a mate-guarding function, and that FGM/C likely originated subsequently and almost exclusively in societies already practicing MGM/C, where it may have become a signal of chastity. Both practices are believed to have originated multiple times, some as early as in the mid-Holocene (5,000–7,000 years ago). The study posits that GM/C co-evolves with and may help maintain fundamental social structures and that the high fitness costs of FGM/C are offset by social benefits, such as enhanced marriageability and social capital.

This article presents codes for adolescent initiation ceremonies in the standard cross-cultural sample. Commonly held assumptions about initiation ceremonies were not supported. Article focuses on differences between male and female ceremonies. Statistically significant correlations between the codes are indicated.

Female genital mutilations within Africa are associated with strong fraternal interest groups, virginity tests, and conservative permarital sex norms. Codes and ratings for female genital mutilations, virginity tests, premarital sex norms, and female initiation rites are presented in this article.

This article examines correlates of sexual fear among men and women. The author concludes that the more authority men have over women, the more women will dread male genitals and vice versa.

This study differentiates between circumcision and supercision, two male genital mutilations which are thought to correlate with different gender socialization processes. Results suggest that circumcision occurs in societies with higher sexual differentiation in socialization while supercision occurs in societies with lower sexual differentiation in socialization.

This article tests four hypotheses regarding scarification, which is described as 1) a rite of passage, 2) a hardening/trauma procedure, 3) a nonadaptive sexually selected character, or 4) an adaptive pathogen driven sexually selected character. Only the third hypothesis is supported in a worldwide sample, suggesting that scarification is associated with polygyny. The other three are each supported in different regional subsamples—principally the first hypothesis (supported in Africa, the Insular Pacific, and South America).

Textor summarizes cross-cultural male initiation rites findings pertaining to cultural, environmental, psychological, and social phenomena.

This article examines the "sexual conflict" hypothesis which predicts that male genital mutilation should be associated with polygyny and a reduction in the frequency of extramarital sex. Male genital mutilation (MGM) rituals should be highly public and facilitate access to social benefits. Support for these assumptions is provided.

This article examines the relationship between polygynous living quarter arrangements and the presence or absence of circumcision and segregation of males at puberty. The amount of contact between the father and son is also examined as a factor.