Xiaofeng Yin1,2, Miho S Kitazawa3,4. 1. Department of Biological Sciences, Graduate School of Science, The University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo, 113-0033, Japan. yinx@g.ecc.u-tokyo.ac.jp. 2. Japan Society for the Promotion of Science, Tokyo, Japan. yinx@g.ecc.u-tokyo.ac.jp. 3. Center for Education in Liberal Arts and Sciences, Osaka University, 1-16 Machikaneyama-cho, Toyonaka, Osaka, 560-0043, Japan. kitazawa@celas.osaka-u.ac.jp. 4. Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka, 560-0043, Japan. kitazawa@celas.osaka-u.ac.jp.