Now you see me, now you don't: evidence that chimpanzees understand the role of the eyes in attention

Chimpanzees appear to understand something about the attentional states of others; in the present experiment, we investigated whether they understand that the attentional state of a human is based on eye gaze. In all, 116 adult chimpanzees were offered food by an experimenter who engaged in one of the four experimental manipulations: eyes closed, eyes open, hand over eyes, and hand over mouth. The communicative behavior of the chimpanzees was observed. More visible behaviors were produced when the experimenter's eyes were visible than when the experimenter's eyes were not visible. More vocalizations were produced when the experimenter's eyes were closed than when they were open, but there were no differences in other attention getting behaviors. There was no effect of age or rearing history. The results suggest that chimpanzees use the presence of the eyes as a cue that their visual gestures will be effective.

[1]  Brian Hare,et al.  Can competitive paradigms increase the validity of experiments on primate social cognition? , 2001, Animal Cognition.

[2]  Charlie Lewis,et al.  Children's Early Understanding of Mind: Origins and Development , 1994 .

[3]  D. Povinelli,et al.  Chimpanzees: Joint Visual Attention , 1996 .

[4]  Michael Tomasello,et al.  Use of gesture sequences in chimpanzees , 2004, American journal of primatology.

[5]  D. Povinelli,et al.  Do chimpanzees tailor their gestural signals to fit the attentional states of others? , 1999, Animal Cognition.

[6]  David A. Leavens,et al.  Intentional communication by chimpanzees: a cross-sectional study of the use of referential gestures. , 1998, Developmental Psychology.

[7]  A. Harcourt.  The Chimpanzees of Gombe. Patterns of Behavior, Jane Goodall. Belknap Press of Harvard University Press, Cambridge, Massachussets (1986), xii, +671. Price $30 , 1988 .

[8]  A. Machado,et al.  YOU CAN LEAD AN APE TO A TOOL, BUT …: A REVIEW OF POVINELLI'S FOLK PHYSICS FOR APES: THE CHIMPANZEE'S THEORY OF HOW THE WORLD WORKS , 2003 .

[9]  R. Seyfarth,et al.  Attending to behaviour versus attending to knowledge: examining monkeys' attribution of mental states , 1990, Animal Behaviour.

[10]  M. Tomasello,et al.  Body orientation and face orientation: two factors controlling apes’ begging behavior from humans , 2004, Animal Cognition.

[11]  Michael Tomasello,et al.  All great ape species follow gaze to distant locations and around barriers. , 2005, Journal of comparative psychology.

[12]  Michael Tomasello,et al.  The learning and use of gestural signals by young chimpanzees: A trans-generational study , 1994, Primates.

[13]  A. Meltzoff,et al.  The importance of eyes: how infants interpret adult looking behavior. , 2002, Developmental psychology.

[14]  M. Krause,et al.  Chimpanzee (Pan troglodytes) pointing: hand shapes, accuracy, and the role of eye gaze. , 1997, Journal of comparative psychology.

[15]  MICHAEL TOMASELLO,et al.  Chimpanzees, Pan troglodytes, follow gaze direction geometrically , 1999, Animal Behaviour.

[16]  G. Butterworth,et al.  Pointing and social awareness: declaring and requesting in the second year , 1996, Journal of Child Language.

[17]  D. Povinelli,et al.  A Longitudinal Investigation of Chimpanzees' Understanding of Visual Perception , 1999 .

[18]  D. Povinelli.  Folk physics for apes , 2000 .

[19]  M. Tomasello,et al.  Domestic Dogs (Canis familiaris) Use Human and Conspecific Social Cues to Locate Hidden Food , 1999 .

[20]  G. Butterworth,et al.  What minds have in common is space : Spatial mechanisms serving joint visual attention in infancy , 1991 .

[21]  D. Povinelli,et al.  Factors influencing young chimpanzees' (Pan troglodytes) recognition of attention. , 1996, Journal of comparative psychology.

[22]  David A. Leavens,et al.  Tactical use of unimodal and bimodal communication by chimpanzees, Pan troglodytes , 2004, Animal Behaviour.

[23]  M. Tomasello,et al.  Cues to food location that domestic dogs (Canis familiaris) of different ages do and do not use , 2000, Animal Cognition.

[24]  David A. Leavens,et al.  Theory of mind in nonhuman primates , 1998, Behavioral and Brain Sciences.

[25]  David A. Leavens,et al.  Intentional Communication by Chimpanzees: A Cross-Sectional Study of the Use of Referential Gestures , 1998 .

[26]  Autumn B. Hostetter,et al.  Differential use of vocal and gestural communication by chimpanzees (Pan troglodytes) in response to the attentional status of a human (Homo sapiens). , 2001, Journal of comparative psychology.