Travel fosters tool use in wild chimpanzees

  1. Thibaud Gruber  Is a corresponding author
  2. Klaus Zuberbühler
  3. Christof Neumann
  1. University of Neuchâtel, Switzerland
  2. Université de Neuchâtel, Switzerland

Abstract

Ecological variation influences the appearance and maintenance of tool use in animals, either due to necessity or opportunity, but little is known about the relative importance of these two factors. Here, we combined long-term behavioural data on feeding and travelling with six years of field experiments in a wild chimpanzee community. In the experiments, subjects engaged with natural logs, which contained energetically valuable honey that was only accessible through tool use. Engagement with the experiment was highest after periods of low fruit availability involving more travel between food patches, while instances of actual tool-using were significantly influenced by prior travel effort only. Additionally, combining data from the main chimpanzee study communities across Africa supported this result, insofar as groups with larger travel efforts had larger tool repertoires. Travel thus appears to foster tool use in wild chimpanzees and may also have been a driving force in early hominin technological evolution.

Article and author information

Author details

  1. Thibaud Gruber

    Department of Comparative Cognition, University of Neuchâtel, Neuchâtel, Switzerland
    For correspondence
    thibaud.gruber@gmail.com
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-6766-3947
  2. Klaus Zuberbühler

    Department of Comparative Cognition, Université de Neuchâtel, Neuchâtel, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
  3. Christof Neumann

    Department of Comparative Cognition, University of Neuchâtel, Neuchâtel, Switzerland
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0236-1219

Funding

European Commission (329197)

  • Thibaud Gruber

European Commission (283871)

  • Klaus Zuberbühler

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Animal experimentation: Permission to conduct the chimpanzee research was given by Uganda Wildlife Authority (UWA, permit FOD/33/02 to TG) and Uganda National Council for Science and Technology (UNCST, permit ns431 to TG). Research protocols were reviewed and approved by the veterinary staff at Budongo Conservation Field Station. Ethical approval was given by the Ethics Committees at the School of Psychology, University of St Andrews and the University of Neuchâtel.

Copyright

© 2016, Gruber et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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https://doi.org/10.7554/eLife.16371

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