The presence of females induces elevated cortisol levels in an alpha male
Experimental evidence in chimpanzees
Bibliographic Data
OBJECTIVES: In group-living primates, it has been reported that the alpha male exhibits high concentrations of cortisol and testosterone in the context of mating competition. We investigated how the presence of females affected salivary cortisol and testosterone levels in males from a small captive group of chimpanzees (Pan troglodytes). Specifically, we assessed whether the presence of females resulted in a rapid increase in salivary cortisol and testosterone levels in the alpha male. MATERIALS AND METHODS: We compared the social behavior and salivary hormone concentrations of four males before and after the presentation of receptive females. Three times a day, we collected saliva samples, a useful matrix for investigating short-term hormonal changes, and measured cortisol and testosterone concentration by liquid chromatography-tandem mass spectrometry (LC-MS/MS). RESULTS: The frequency of inter-male aggression increased in the presence of females, indicating intense competition among males. Salivary cortisol levels increased in all males in the presence of females; however, the increase was significantly more pronounced in the alpha male. We found a complex three-way interaction among the presence of females, sampling timings, and male dominance rank in the analysis of salivary testosterone. Contrary to our prediction, a post hoc analysis revealed that salivary testosterone levels decreased after female introduction and that the alpha male did not show a higher level of salivary testosterone. CONCLUSIONS: Our study provides experimental evidence suggesting that the presence of females plays a significant role in the rank-related variation in the cortisol levels in male chimpanzees. Furthermore, our findings demonstrate the usefulness of salivary hormones for detecting short-term physiological changes in studies of socioendocrinology
Aggression · Androgen · Biology · Context (archaeology) · Developmental psychology · Dominance (genetics) · Hormone · Saliva · Testosterone (patch) · Endocrinology · Evolutionary Psychology and Human Behavior · Internal Medicine · Medicine · Primate Behavior and Ecology · Psychology · Stress Responses and Cortisol
Female parity, male aggression, and the Challenge Hypothesis in wild chimpanzees
Female sexual swelling size, timing of ovulation, and male behavior in wild West African chimpanzees
The "Challenge Hypothesis"
Are subordinates always stressed? a comparative analysis of rank differences in cortisol levels among primates
Dominance, aggression and testosterone in wild chimpanzees
Male dominance rank and reproductive success in chimpanzees, Pan troglodytes schweinfurthii
The Influence of Social Hierarchy on Primate Health
Salivary cortisol in psychoneuroendocrine research
Observational Study of Behavior
Dominance rank and fecal testosterone levels in adult male Chimpanzees ( Pan troglodytes schweinfurthii ) at Ngogo, Kibale National Park, Uganda
Validation of a cortisol enzyme immunoassay and characterization of salivary cortisol circadian rhythm in chimpanzees ( Pan troglodytes )
The relationship between socio‐sexual behavior and salivary cortisol in bonobos
Validation of salivary cortisol and testosterone assays in chimpanzees by liquid chromatography‐tandem mass spectrometry
The first chimpanzee sanctuary in Japan
Hormones and social behavior in primates
Cooperation and competition in chimpanzees
Testosterone in juvenile and adolescent male chimpanzees (Pan troglodytes)
Paternity and social rank in wild chimpanzees ( Pan troglodytes ) from the Budongo Forest, Uganda
Ethogram and Ethnography of Mahale Chimpanzees
Current Topics in Primate Socioendocrinology
| Citation velocity | historical |
|---|---|
| Highly cited | No |