Marital Status and Sleeping Arrangements Predict Salivary Testosterone Levels in Rural Gambian Men

Abstract

Variation in male testosterone has been hypothesized to reflect the evolved hormonal regulation of investment in mating versus parenting effort. Supporting this hypothesis, numerous studies have observed lower testosterone in married men and fathers compared with unpartnered and childless men, consistent with relatively elevated resource allocation to parenting as opposed to mating effort. Furthermore, lower testosterone has been reported among fathers more actively engaged in direct caregiving. However, it remains unclear whether these findings generalize cross-culturally. Most studies have been conducted in relatively urban, affluent, and low fertility settings where marriage is predominantly monogamous. We contribute new data on testosterone variation in 100 rural Gambian men from a polygynous, high fertility population, where cultural norms dictate that marriage and fatherhood occur in close succession. Married men (almost exclusively fathers) had lower average morning salivary testosterone than unmarried men (almost exclusively childless). This difference, however, could not be statistically differentiated from declines in testosterone observed with age. Independently of age differences and other potential confounds, we find that (i) among married men, polygynously married men had higher afternoon testosterone than monogamously married men; and (ii) fathers who sleep in the same room as their children had lower morning and afternoon testosterone than those who sleep apart from their children. We also document that body mass index was positively associated with afternoon testosterone. These findings, from a novel setting, provide additional support for the hypothesis that testosterone regulates human paternal care.

Does a man's testosterone “rebound” as dependent children grow up, or when pairbonds end? A test in Cebu, Philippines

“…One reason men's physiology might move toward higher T is the inevitable caretaking changes that occur as children age. Previous work suggests that T is specifically sensitive to the amount of direct care that men do (Alvergne et al, ; Gettler, McDade, Agustin, Feranil, & Kuzawa, ; Gettler, McKenna, McDade, Agustin, & Kuzawa, ; Lawson et al, ; Mascaro, Hackett, & Rilling, ; Muller et al, ). As children grow older they require less of this type of care (eg, Aldous, Mulligan, & Bjarnason, ; Yeung, Sandberg, Davis‐Kean, & Hofferth, ).…”

Sociosexuality, testosterone, and life history status: prospective associations and longitudinal changes among men in Cebu, Philippines

“…Longitudinal studies have shown that men's T declines when they transition to long-term committed relationships and fatherhood (Edelstein et al, 2015;Gettler, McDade, Feranil, & Kuzawa, 2011;Holmboe et al, 2017;Mazur & Michalek, 1998;Saxbe et al, 2017). In multiple cultural contexts, fathers with lower T tend to engage in more direct childcare, and partnered men and women also report lower relationship satisfaction and commitment when they have elevated T (Alvergne, Faurie, & Raymond, 2009;Edelstein et al, 2017;Edelstein, van Anders, Chopik, Goldey, & Wardecker, 2014;Gettler et al, 2011;Gettler, Mc-Dade, Bragg, Feranil, & Kuzawa, 2015;Lawson et al, 2017;Mascaro, Hackett, & Rilling, 2013;Muller, Marlowe, Bugumba, & Ellison, 2009). These psychobiological patterns are consistent with T's role in mediating life history trade-offs related to mating/competition and investments in nurturing partnering and parenting (van Anders, 2013).…”

Exploring the links between early life and young adulthood social experiences and men's later life psychobiology as fathers

“…As noted above, there is evidence to support this proposition. Within societies, T is lower among fathers who report spending more time in direct care [20,40,60] or who co-sleep with their children [21,39].…”