The ontogeny of gaze following in chimpanzees, Pan troglodytes, and rhesus macaques, Macaca mulatta

• Published in: Animal behaviour Vol. 61; no. 2; pp. 335 - 343
• Main Authors: Tomasello, Michael, Hare, Brian, Fogleman, Tara
• Format: Journal Article
• Language: English
• Published: Kent Elsevier Ltd 01.02.2001; Elsevier; Harcourt Brace Jovanovich Ltd
• Subjects: Animal behavior; Animal cognition; Animal ethology; Biological and medical sciences; Conspecifics; Eyes & eyesight; Fundamental and applied biological sciences. Psychology; Macaca mulatta; Mammalia; Pan troglodytes; Primates; Psychology. Psychoanalysis. Psychiatry; Sensory perception; Vertebrata; Gaze; Interspecific comparison; Social learning; Cognition; Macaca mulatta; Pan troglodytes; Orientation; Behavioral ontogeny; Vertebrata; Mammalia; Acquisition process; Primates; Simioidea; Captivity; Developmental stage; Age; Interspecific relation
• ISSN: 0003-3472; 1095-8282
• DOI: 10.1006/anbe.2000.1598

Primates follow the gaze direction of conspecifics to outside objects. We followed the ontogeny of this social-cognitive skill for two species: rhesus macaques and chimpanzees. In the first two experiments, using both a cross-sectional and a longitudinal design, we exposed individuals of different ages to a human looking in a specified direction. Rhesus infants first began reliably to follow the direction of this gaze at the end of the early infancy period, at about 5.5 months of age. Chimpanzees did not reliably follow human gaze until 3–4 years; this corresponds to the latter part of the late infancy period for this species. In the third experiment we exposed individuals of the same two species to a human repeatedly looking to the same location (with no special object at that location) to see if subjects would learn to ignore the looks. Only adults of the two species diminished their gaze-following behaviour over trials. This suggests that in the period between infancy and adulthood individuals of both species come to integrate their gaze-following skills with their more general social-cognitive knowledge about other animate beings and their behaviour, and so become able to deploy their gaze-following skills in a more flexible manner.