Begging gesture and understanding others' attentional states in chimpanzees and capuchin monkeys
Date:2007/08/14 - 2007/08/24
I presented a 5min-poster talk and a poster entitled "Begging for food vs. on the table : Chimpanzees and capuchin monkeys understand other's attentional states", jointly authored with K. Kuroshima (JSPS, University of Georgia), M. Tomonaga (Primate Research Institute) and K. Fujita (Kyoto University) on August 16. My poster talk won 3rd prize for student poster talk competition and a commemorative gift was rewarded by Cambridge University Press. The abstract is as follows:
Understanding others's attentional states is considered as an important prerequisite for theory of mind. However, previous studies using food requesting task failed to reveal non-human primates' ability to attribute perception to others depending on subtle attentnional states. As Gomez (2005) argues, previous food requesting tasks may require subjects not only to collect an experimenter's attention but also to direct it toward the food. The present study retested chimpanzees' and tufted capuchin monkeys' understanding of other's attentional states by directly comparing two food requesting contexts: one that requires the subjects only to attract a human experimenter's attention and the other that requires them to both attract the experimenter's attention and direct it toward the food on a table. Only in the former context, the subjects showed evidence of understanding the experimenter's attentional states. The result suggests that the previous task requiring referential gestures, which most of non-human primates lack, interfered subjects from understanding the tasks. Species differences between capuchins and chimpanzees were also found in the performances and variety of begging gestures, suggesting that the recognition of the situation is different between these two species.