Social Hair Plucking's Associations with Other Behaviors and Its Health Considerations in Captive Rhesus Macaques (Macaca mulatta)

The study investigated social hair plucking (SHP) in seven mixed-sex groups of captive rhesus macaques to explore its associations with grooming, aggression, and health-related factors. SHP rates were similar to grooming and aggression, showing directional rank flow like aggression and kin biases like grooming. SHP given was linked to shared kinship, suggesting social transmission, while SHP received was associated with alopecia. In females, SHP given correlated with hair cortisol concentrations, though with high uncertainty. The study concludes that SHP is an abnormal behavior with both prosocial and aggressive characteristics and health implications. Further research is recommended to understand SHP across species.