Leaf-grooming by a wild chimpanzee in Mahale
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1Laboratory of Human Evolution Studies, Department of Zoology, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo, Japan. zamma@jinrui.zool.kyoto-u.ac.jp
Abstract:
During the course of systematic observations of the leaf-grooming behavior by the chimpanzees (Pan troglodytes) of the Mahale Mountains National Park, Tanzania, I recovered a louse from a leaf "groomed" by an adult male chimpanzee after a typical leaf-grooming session. During the leaf-grooming session I observed a small object on his lower lip. He picked up a leaf, transferred the small object from his lip to the leaf, folded the leaf and crushed the folded side of the leaf with his thumb. I present this observation as further evidence of the "squashing ectoparasites" hypothesis for leaf-grooming.
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