Abstract
We captured 26 males for marking with tattoo using a blowpipe dart containing anesthetic. Individuals shot with a blowpipe got temporarily disabled. When these individuals were released still being disabled, members of the same troop showed various attitudes toward them. Only young males of 5 to 9 years old received aggressive behaviors. Aggressors were also young males of 7 to 8 years old, and they showed both aggressive and affinitive behaviors against the disabled individuals. An adult male and adult females showed only affinitive behaviors, and they protected the disabled individuals from the attack by young males. Close and unstable dominance relationships might cause the aggressive interactions between young males.
