During food competition experiments, male bonobos' cortisol levels increased when a dominant partner was expected to monopolize food and decreased when food was expected to be shared, whereas male chimpanzees showed changes in testosterone instead.
Notes on verification
Confirmed by peer-reviewed PNAS study (Wobber et al. 2010), corroborated by PubMed abstract and independent secondary sources (NBC News, anthropology blog).
Sources
- Comparative Cognitive Development (dash.harvard.edu)
- https://www.pnas.org/doi/10.1073/pnas.1007411107 (pnas.org)
- https://pubmed.ncbi.nlm.nih.gov/20616027/ (pubmed.ncbi.nlm.nih.gov)
- https://www.nbcnews.com/health/health-news/men-are-apes-when-competing-status-flna1c9456563 (nbcnews.com)