Structural variability in primate vocalizations and its functional significance: an analysis of squirrel monkey chuck calls.
Sound spectrograms of vocalizations recorded from 'Gothic arch' squirrel monkeys were examined for shared structural characteristics. A rapidly descending element, the 'mast', was found to be diagnostic for a group of variable but structurally similar vocalizations called chucks. In addition to the mast, a variable FM element ('flag') and a terminal noisy element ('cackle') formed a basic 3-element structural unit. A review of functional studies suggests that this flag-mast-cackle structure is used by the squirrel monkey and a variety of other New World primates in circumstances involving close social contact.
D000818:Animals; D002427:Cebidae; D005260:Female; D008297:Male; D012453:Saimiri; D012919:Social Behavior; D013018:Sound Spectrography; D014828:Vocalization, Animal