Primates

, Volume 47, Issue 2, pp 113–122

Tool-use for drinking water by immature chimpanzees of Mahale: prevalence of an unessential behavior

Authors

    • Laboratory of Human Evolution Studies, Graduate School of ScienceKyoto University
  • Hitonaru Nishie
    • Laboratory of Human Evolution Studies, Graduate School of ScienceKyoto University
  • Masaki Shimada
    • Laboratory of Human Evolution Studies, Graduate School of ScienceKyoto University
  • Nobuyuki Kutsukake
    • Department of Cognitive and Behavioral Science, Graduate School of Arts and SciencesThe University of Tokyo
  • Koichiro Zamma
    • Primate Research InstituteKyoto University
  • Michio Nakamura
    • Laboratory of Human Evolution Studies, Graduate School of ScienceKyoto University
  • Toshisada Nishida
    • Japan Monkey Centre
Original Article

DOI: 10.1007/s10329-005-0158-4

Cite this article as:
Matsusaka, T., Nishie, H., Shimada, M. et al. Primates (2006) 47: 113. doi:10.1007/s10329-005-0158-4

Abstract

Use of leaves or sticks for drinking water has only rarely been observed during long-term study of wild chimpanzees (Pan troglodytes schweinfurthii) at Mahale. Recently, however, we observed 42 episodes of tool-use for drinking water (73 tools and two cases of using “tool-sets”) between 1999 and 2004. Interestingly, all of the performers were immature chimpanzees aged from 2 to 10 years. Immature chimpanzees sometimes observed the tool-using performance of others and subsequently reproduced the behavior, while adults usually paid no attention to the performance. This tool-use did not seem to occur out of necessity: (1) chimpanzees often used tools along streams where they could drink water without tools, (2) they used tools for drinking water from tree holes during the wet season when they could easily obtain water from many streams, and (3) the tool-using performance sometimes contained playful aspects. Between-site comparisons revealed that chimpanzees at drier habitats used tools for drinking water more frequently and in a more “conventional” manner. However, some variations could not be explained by ecological conditions. Such variations and the increase in this tool-use in recent years at Mahale strongly suggest that social learning plays an important role in the process of acquiring the behavior. We should note here that such behaviors that lack obvious benefits or necessity can be prevalent in a group.

Keywords

Chimpanzees (Pan troglodytes schweinfurthii)CultureMahaleTool-setsTool-use to drink water

Copyright information

© Japan Monkey Centre and Springer-Verlag 2005