The function and mechanisms underlying baboon ‘contact’ barks

摘要: Free-ranging baboons, Papio cynocephalus ursinus, in the Okavango Delta, Botswana, often give loud 'contact' barks when separated from other group members. Although these calls appear to function maintain contact between widely dispersed animals, individuals apparently do not with intent of informing others their location. Females are more likely a bark 5 min after they themselves have called than another female has called. Playback experiments suggest that females primarily 'answer' close relatives' or at end progression. ? 1996 The Association for Study Animal Behaviour When moving through wooded areas, free-ranging chacma ursinus ,i n loud, tonal (Fig. 1) can be heard up 200 m away. These acoustically distinctive and easily distinguished, both spectrographi- cally by ear, baboons' vocal repertoire (R. Seyfarth & D. Cheney, un- published data). as calls, because seem ex- changed sub-groups individuals. previously described populations savanna baboons East Southern Africa, functionally similar forest Guinea P. c. papio (Byrne 1981), mandrills, sphynx (Kudo 1987). Analogous occur primate species. In squirrel monkeys, Saimiri sciureus (Boinski 1991), white-faced capuchins, Cebus capucinus 1993), example, trills seems only cohesion but also initiate set direction group's movement. some species, long distance may serve conditional recruitment signals attract food. Foraging sub- groups spider Ateles geoVroyi (Chapman Levebre 1990), chimpanzees, Pan troglodytes (Wrangham 1977; Clark Wrangham 1994), upon arriving food resources. Typically, given large patches small ones.