Responses of Rhesus Monkeys to Separation Vocalizations of a Conspecific Infant

Abstract

The vocalizations of a rhesus monkey infant were recorded immediately following separation of the infant from its mother. The recorded vocalizations were played to 12 young adult rhesus monkeys, 6 of each sex. The adults were less active during the time when the recorded vocalizations were being played than during equivalent periods of time before and after the stimulus tape had been played. Ss also spent more time near the stimulus source and looked at it longer when infant vocalizations were audible. Two of the females responded to the infant sounds immediately by looking down at their breasts and by displaying retrieval or support postures typical of mother monkeys with small infants.