Ecology of Tool Use in Wild Chimpanzees: Toward Reconstruction of Early Hominid Evolution

  • Gen Yamakoshi


The emergence and evolution of human technology is a central issue in evolutionary anthropology. To date, most evidence has come from stone artifacts found together with hominid fossils (e.g., Leakey 1971). The oldest known stone tools manufactured by hominids date back to about 2.5 million years ago (Semaw et al. 1997). According to recent molecular studies, however, the human lineage diverged from the chimpanzee-bonobo lineage about 6 million years ago (e.g., Sibley and Ahlquist 1984). It follows that we have no evidence of tool use by early hominids from the period 6-2.5 million years ago, more than half of hominid history. Should we assume that they did not use tools? The answer is probably no. Because organic matter such as sticks and leaves is the material most likely to have been used by early hominids for tools, any artifacts would quickly have decomposed and are unlikely to have been fossilized. Many textbooks end their discussion simply by saying that early hominids must have used tools to the same extent as modern chimpanzees. However, chimpanzees’ tool use has been regarded as opportunistic, and is thought to have only a trivial effect on their subsistence (e.g., Mann 1972).


Wild Chimpanzee Early Hominid Mahale Mountain Feeding Niche Total Feeding Time 
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© Springer 2008

Authors and Affiliations

  • Gen Yamakoshi
    • 1
  1. 1.Center for African Area StudiesKyoto UniversityKyotoJapan

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