Evolutionary foundation and development of imitation

Masako Myowa-Yamakoshi

Kyoto University, Japan

The purpose of this study was to review a series of experiments on imitation in chimpanzees to help understand human imitation from evolutionary and developmental perspectives. The mechanisms of imitation in the two species were compared focusing on visual-motor information processing. Researchers have argued whether imitation that appears in approximately 9-month-old infants derived from "neonatal imitation”. Recent evidence for neonatal imitation in an infant chimpanzee suggested the evolutionary root of this phenomenon. On the other hand, there appeared to be a substantial difference in the degree to which humans and chimpanzees could imitate a broad range of actions. I evaluated the factors that determine the difficulty in reproducing actions in chimpanzees. Chimpanzees tended to reproduce the demonstrated actions by paying more attention to the directionality of the manipulated objects than to details of the body movements of the demonstrator performing the manipulation. These data suggest discontinuity between neonatal imitation and imitation that develops later in life. A basic difference in visual-motor information processing may be at the core of the difference in the social-cognitive abilities of humans and chimpanzees.

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Myowa-Yamakoshi, M., & Matsuzawa,T. (1999). Factors influencing imitation of manipulatory actions in chimpanzees (Pan troglodytes). Journal of Comparative Psychology, 113, 128-136.

Myowa-Yamakoshi, Masako

Japan Society for the Promotion of Science and

Section of Language and Intelligence, Primate Research Institute, Kyoto University

Inuyama, Aichi 484-8506, Japan

myowa@pri.kyoto-u.ac.jp