RESPONSES TO NATURAL AND SYNTHETIC PHEE CALLS BY COMMON MARMOSETS (CALLITHRIX-JACCHUS)

Captive adult common marmosets (Callithrix jacchus) produce whistle-li ke ''phee'' calls in two contexts: in the home cage, where phee calls may function as part of territorial marking behavior, and when separat ed from social companions, where phee calls may function to reunite co nspecifics. Natural and synthesized calls representing the acoustic st ructure of male and female calls in each context were presented to adu lt marmosets in a playback paradigm. Marmosets demonstrated discrimina tive abilities according to the context of the call and the caller's s ex. Vocal and behavioral responses indicated increased vigilance and t erritorial behavior, following playbacks of naturally produced calls a s well as synthetic calls. All animals scanned more frequently followi ng produced calls as well as synthetic calls. All animals scanned more frequently following natural home cage as well as isolation calls, bu t only increased contact behavior (trills) in response to home cage ca lls. The responses were dimorphic according to the sex of the caller, where adult males scanned more following male calls, and adult females were more aggressive following male and female calls. The differentia l behavioral responses to playbacks of marmoset phee calls suggest a b iological relevance to subtle differences found in the acoustic parame ters of the phee call. (C) 1994 Wiley-Liss, Inc.