Document Type


Publication Date



The physiology of fatherhood is a growing field of study, and variability in hormonal mediators of reproductive effort (e.g. testosterone, cortisol) can predict variability in paternal investment. Studies often find that lower testosterone levels are associated with increased paternal investment, though most studies are conducted under relatively stable ecological conditions. In this paper, we examine parental physiological correlates of crop loss and family health problems among Tsimane forager-horticulturalists following a catastrophic flood in lowland Bolivia. Immediately after a devastating 2014 flood that impacted >75% of Tsimane communities, we conducted structured interviews examining crop losses and morbidity, and collected saliva specimens from 421 parents (n= 292 households) to analyze cortisol and testosterone. Over 98% of interviewees reported horticultural losses, with the average family losing 88% of their crops, while 80% of families reported flood-induced injuries or illnesses. Controlling for age, body mass index, and time of specimen collection, men’s testosterone was negatively associated with both absolute cropland losses (Std. β= −0.16, p=0.037), and percent of cropland lost (Std. β= −0.16, p=0.040). Female testosterone was not associated with crop losses. Using the same control variables, both male and female cortisol was negatively associated with a composite measure of child health burden (fathers: Std. β= −0.34, p<0.001; mothers: Std. β= −0.23, p=0.037). These results are discussed in the cultural context of a strong sexual division of labor among Tsimane; we highlight the physiological and psychosocial costs of experiencing a natural disaster, especially for paternal caregivers in a nutritionally and pathogenically stressed subsistence population where cultigens provide the majority of calories in the diet.


NOTICE: this is the author’s version of a work that was accepted for publication in Physiology & Behavior. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Physiology & Behavior, volume 193, part A, in 2018.

The Creative Commons license below applies only to this version of the article.

Peer Reviewed




Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.