Tool Use in Wild Chimpanzees: New Light From Dark Forests

Abstract

In the early 1960s, direct obserI vations of wild chimpanzees began in the wooded savanna of East Af rica. This work revealed the surpris ing abilities of chimpanzees in using and making tools as well as in hunt ing for meat.1 However, although the majority of chimpanzees live in a forest environment, it was not until 1979, when we started our project in the Ivory Coast, that chimpanzees living in the tropical rain forest were observed on a long-term basis. Ha bituaron to human observers is a long process, for chimpanzees are very shy. Earlier studies relied on ar tificial provisioning to speed up this process. We did not because a feed ing behavior was the main topic of our study. The Tai chimpanzees are today still the only community fully habituated without relying on artifi cial provisioning. Tool use is rare in animals, and the chimpanzees stand out as the most proficient tool users besides humans. Toolmaking is even more rarely observed, and chimpanzees are the only animal species observed to make tools regularly in the wild. Knowledge of tool use in chimpan zees leads to better understanding of what is unique about humans' tool use. Here, we review some of the aspects of the nut-cracking behavior observed in our study community in the tropical rain forest.2