Urinary testosterone levels of wild male bonobos (Pan paniscus) in the Lomako Forest, Democratic Republic of Congo
✍ Scribed by Andrew J. Marshall; Gottfried Hohmann
- Publisher
- John Wiley and Sons
- Year
- 2005
- Tongue
- English
- Weight
- 69 KB
- Volume
- 65
- Category
- Article
- ISSN
- 0275-2565
No coin nor oath required. For personal study only.
✦ Synopsis
We collected urine samples from seven male bonobos (Pan paniscus) in the Eyengo community, Lomako Forest, Democratic Republic of Congo, and assayed them for testosterone (T). T levels averaged 525 pmol/mg Cr in adult males, and 309 pmol/mg Cr in subadult males. We collected hormonal and behavioral data during a period of relative social instability following the recent arrival of two immigrant males. In concordance with predictions derived from the challenge hypothesis [Wingfield et al., American Naturalist 136:829-846, 1990], which relates T to levels of reproductive aggression, the alpha male had the highest circulating levels of T. When we removed the two recent immigrant males from the analysis, there was a significant positive correlation between T levels and dominance rank for the long-term resident males (n=5, P=0.001, r 2 =0.98). These are the first data on T levels in wild bonobos, and the results suggest that further study of the relationship between T levels and social context in this species could inform current models relating hormones and aggression in wild apes. Am.