chimpanzees kept in European zoos are of the west African subspecies, behavior of captive chimpanzees provide much information on this subspecies. Behavioral patterns belonging to Categories 5, or 7 are most likely to be cultural, but their status remains ambiguous, until it is determined by careful comparison whether the environmental factors that might explain the local differences are present or absent. Methods In compiling an audio-visual ethogram of Mahale chimpanzees, we mostly followed principles used by Nishida et al. First, we tried to make the ethogram maximally inclusive. Second, we distinguished functional definitions from anatomical ones. Elements of the latter should be provided for all functionally-defined behavioral patterns. In order to attain this goal, we adopted the format of putting verbs in front of nouns or adjectives for