1. Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences; Institute of Vertebrate Palaeontology and Palaeoanthropology, Chinese Academy of Sciences; 142 Xizhimenwai Street Beijing 100044 China
2. Institute of Archaeology; Chinese Academy of Social Sciences; 27 Wangfujing Street Beijing 100710 China
3. State Key Laboratory of Nonlinear Mechanics (LNM); Institute of Mechanics, Chinese Academy of Sciences; Beijing 100190 China