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Updated: Aug 13, 2026

Combining Behavioral Endocrinology and Experimental Economics: Testosterone and Social Decision Making
Published on: March 2, 2011
Marriage, parenting, and testosterone variation among Kenyan Swahili men
1Department of Anthropology, Harvard University, Cambridge, Massachusetts 02138, USA. gray@fas.harvard.edu
Abstract:
Male variation in testosterone (T) levels may, in part, reflect a differential behavioral allocation to mating and parenting effort. This research tests whether demographic indicators of pair bonding and parenting were associated with salivary T levels among Kenyan Swahili men. Men in the sample were either unmarried (N = 17), monogamously married (N = 57), or polygynously married (N = 14), and between ages 29-52. In contrast with earlier findings among North American men, monogamously married men did not have lower T levels than unmarried men. However, among all married men, men with younger genetic children tended to have marginally lower T levels. Polygynously married men, all of whom had two wives, had higher T levels than all other Swahili men. Possible explanations of higher T levels among polygynously married men are explored.
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