Pre-feeding Agonism and Seasonality in Captive Groups of Chimpanzees (Pan Troglodytes)

Captive chimpanzees fed at regular, predictable intervals are known to exhibit higher rates of aggression immediately prior to, and during feeding. Presumably, anticipation of food creates tensions leading to increased agonistic interactions prior to feeding. This study was conducted to determine if seasonal variabilities might contribute to pre-feeding agonism. A quantitative examination was made looking […]

The effect of energetic and psychosocial stressors on glucocorticoids in mantled howler monkeys (Alouatta palliata)

The proximate causes of variation in glucocorticoids (GCs) of many free-ranging primates are still unclear, and in some cases, the available evidence is contradictory. Such is the case of mantled howler monkeys. In the present study, we tested whether variation in GC levels in this species could be predicted by energetic challenges or by psychosocial […]