Animal Cognition

, Volume 6, Issue 4, pp 199–211 | Cite as

The Ai project: historical and ecological contexts

  • Tetsuro Matsuzawa


This paper aims to review a long-term research project exploring the chimpanzee mind within historical and ecological contexts. The Ai project began in 1978 and was directly inspired by preceding ape-language studies conducted in Western countries. However, in contrast with the latter, it has focused on the perceptual and cognitive capabilities of chimpanzees rather than communicative skills between humans and chimpanzees. In the original setting, a single chimpanzee faced a computer-controlled apparatus and performed various kinds of matching-to-sample discrimination tasks. Questions regarding the chimpanzee mind can be traced back to Wolfgang Koehler’s work in the early part of the 20th century. Yet, Japan has its unique natural and cultural background: it is home to an indigenous primate species, the Japanese snow monkey. This fact has contributed to the emergence of two previous projects in the wild led by the late Kinji Imanishi and his students. First, the Koshima monkey project began in 1948 and became famous for its discovery of the cultural propagation of sweet-potato washing behavior. Second, pioneering work in Africa, starting in 1958, aimed to study great apes in their natural habitat. Thanks to the influence of these intellectual ancestors, the present author also undertook the field study of chimpanzees in the wild, focusing on tool manufacture and use. This work has demonstrated the importance of social and ecological perspectives even for the study of the mind. Combining experimental approaches with a field setting, the Ai project continues to explore cognition and behavior in chimpanzees, while its focus has shifted from the study of a single subject toward that of the community as a whole.


Nonhuman Primate Stone Tool Japanese Monkey Wild Chimpanzee Female Chimpanzee 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The present study has been supported by Grants from the Ministry of Education, Culture, Sports, Science and Technology (Nos 07102010, 12002009, 10CE2005, the 21st Century COE program A2 to Kyoto University, and others). Thanks are due to Kiyoko Murofushi, Toshio Asano, Shozo Kojima, Sumiharu Nagumo, Kazuo Fujita, Masaki Tomonaga, Masayuki Tanaka, Shoji Itakura, Nobuyuki Kawai, Masako Myowa-Yamakoshi, Satoshi Hirata, Claudia Sousa, and other colleagues and students in the laboratory. Thanks are also due to Yukimaru Sugiyama, Gen Yamakoshi, and other colleagues and students in the field. I am also grateful to Dora Biro for a careful reading of the manuscript, comments, and assistance with the English. I also express my thanks to Ai and the other chimpanzees of the KUPRI community, and those living in the Bossou/Nimba communities in Africa.


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Authors and Affiliations

  1. 1.Section of Language and Intelligence, Primate Research InstituteKyoto UniversityJapan

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