Discrte or graded variation within rhesus monkey screams? Pychophysical experiments on classification

摘要

Gouzoules et al. (1984, Animal Behaviour, 32, 182-193) presented evidence that semifree-ranging rhesus monkeys, Macaca mulatta, produce acoustically distinctive classes of scream vocalizations that carry different functional messages. To determine the perceptual validity of these vocal classes, we conducted psychophysical experiments on captive rhesus monkeys. We trained two monkeys to maintain contact with a metal response cylinder during presentation of nontarget stimuli, and to release the cylinder to report detection of target stimuli.