International and Area Studies Commons^™

Age-Independent Increases In Male Salivary Testosterone During Horticultural Activity Among Tsimane Forager-Farmers, Benjamin C. Trumble, Daniel K. Cummings, Kathleen A. O'Connor, Darryl J. Holman, Eric A. Smith, Hillard Kaplan, Michael D. Gurven

ESI Publications

Testosterone plays an important role in mediating male reproductive trade-offs in many vertebrate species, augmenting muscle and influencing behavior necessary for male-male competition and mating-effort. Among humans, testosterone may also play a key role in facilitating male provisioning of offspring as muscular and neuromuscular performance are deeply influenced by acute changes in testosterone. This study examines acute changes in salivary testosterone among 63 Tsimane men ranging in age from 16–80 (mean 38.2) years during one-hour bouts of treechopping while clearing horticultural plots. The Tsimane forager-horticulturalists living in the Bolivian Amazon experience high energy expenditure associated with food production, have high …