Infidelity, jealousy, and wife abuse among Tsimane forager–farmers: testing evolutionary hypotheses of marital conflict

Abstract

The role of men's jealousy over a wife's infidelity in precipitating marital conflict and wife abuse is well documented. The role of women's jealousy over a husband's infidelity has received little attention, which is puzzling given high potential costs to women of withdrawal of paternal investment. We address this gap by investigating marital conflict and wife abuse among Tsimane forager–farmers of Bolivia. We test predictions derived from male jealousy and paternal disinvestment hypotheses, which consider threats and consequences of infidelity by women (male jealousy hypothesis) and men (paternal disinvestment hypothesis). The paternal disinvestment hypothesis proposes that wife abuse is employed by husbands to limit wives' mate retention effort and maintain men's opportunities to pursue extrapair sexual relationships. Interviews were conducted among husbands and wives in the same marriages using a combination of open-ended and structured items. Spouses agree that the most frequently reported type of marital argument is women's jealousy over a husband's infidelity (N=266 arguments). Roughly 60% of abusive events occurred during arguments over men's diversion of household resources (N=124 abusive events). In multivariate analyses, likelihood of wife abuse is greater in marriages where husbands have affairs, where wives are younger, and where spouses spend more time apart (N=60 husbands, 71 wives). While we find strong support for both male jealousy and paternal disinvestment hypotheses, it is men's infidelity, not women's, that precipitates most instances of marital conflict and wife abuse. We conclude that men's aggression towards their wives facilitates men's diversion of family resources for their selfish interests.