LETHAL TERRITORIAL AGGRESSION IN A WHITE-HANDED GIBBON

During an intergroup conflict an adult male white-handed gibbon (Hylob ates lar) from one group was attacked and wounded by the adult male of a neighboring group. The wounded male's calling behavior, general act ivity level, feeding, and participation in territorial defense decline d dramatically in the days following the injury as he instead spent lo ng periods resting and tending the wound. The normal and healthy appea rance of this male prior to injury, the circumstances of the fight tha t caused the injury, the resultant deterioration in normal maintenance and social behavior, and finally the apparent infection of the wound by insect larvae all suggested that his disappearance 24 days later wa s the result of death due directly or indirectly to the wound he had s uffered. The observations reported here suggest that the ritualization of territorial aggression in this species has not eliminated risks of serious injury and death. (C) 1993 Wiley-Liss, Inc.