1. Center for International Collaboration and Advanced Studies in Primatology (CICASP) & Section of Language and Intelligence, Kyoto University Primate Research Institute, 41-2 Kanrin, Inuyama, Aichi 484-8506, Japan
2. Kyoto University Institute for Advanced Study (KUIAS), Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan