Urinary Testosterone Metabolite Levels in Captive Bonobos: Relationship with Age

Sannen, Adinda; Elsacker, Linda Van; Eens, Marcel; Heistermann, Michael

doi:10.1159/000076271

Cited by 4 publications

(1 citation statement)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Rank was regarded as the independent covariate and period was assigned as the independent grouping variable. Sex and age were included to correct for an effect on T levels (for sex, see Sannen et al 2003a; for age, see Sannen et al 2004). The model furthermore tested the interaction of rank with period (rank*period).…”

Section: Statistical Analysesmentioning

confidence: 99%

Urinary testosterone-metabolite levels and dominance rank in male and female bonobos ( Pan paniscus )

et al. 2004

Self Cite

View full text Add to dashboard Cite

The correlation between testosterone (T) and dominance rank may vary among species, and is expected to become stronger as the importance of aggressive competition for rank increases. However, it may also vary among social situations within a species, showing a stronger correlation during socially unstable periods. Knowledge on this topic in great apes, especially in females, is scant. This study presents the first data on the relationship between T and dominance rank in both sexes of the bonobo ( Pan paniscus). For each period (four socially unstable and two stable ones), linear rank orders were determined and subsequently correlated with the accompanying mean urinary T-metabolite concentrations (measured as immunoreactive 5alpha-androstan-17alpha-ol-3-one). No correlation between these two variables was found for either sex among individuals during socially unstable or stable periods. Also, within an individual over the six periods, no relationship of T with rank could be demonstrated. These results suggest that either the outcomes of aggressions have no influence on T levels, or such clear outcomes appear insufficiently frequent to affect T levels over longer periods. Even during the unstable periods, the rate of aggressions was not higher than during stable periods, suggesting that frequencies of aggression have little effect on rank. Further analyses indeed demonstrated no correlation between frequencies of overall aggressions or any type of aggressive behavior separately, or rank. Perhaps factors other than the frequency of displayed aggressions alone have a marked influence on a bonobo's rank, for example, coalition partners. Overall, in bonobos, T apparently does not form a physiological reflection of social status.

show abstract

Section: Statistical Analysesmentioning

confidence: 99%