1. Department of Earth and Environmental Science, University of Pennsylvania, 251 Hayden Hall, 240 South 33rd Street, Philadelphia, Pennsylvania 19104, U.S.A.;
2. Department of Biology, Indiana University of Pennsylvania, Weyandt Hall Room 114, 975 Oakland Avenue, Indiana, Pennsylvania 15705, U.S.A., ;
3. Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, 142 Xizhimenwai Street, Beijing 100044, People’s Republic of China, ;
4. Chinese Academy of Sciences Center for Excellence in Life and Paleoenvironment, 142 Xizhimenwai Street, Beijing 100044, People’s Republic of China;
5. University of Chinese Academy of Sciences, 19A Yüquan Road, Beijing 100049, People’s Republic of China;
6. Laboratory of Vertebrate Evolution and Fossil Conservation Technology, Gansu Agricultural University, 1 Yingmencun, Anning District, Lanzhou City, Gansu Province 730070, People’s Republic of China, ;
7. Department of Biomedical Sciences, School of Veterinary Medicine, University of Pennsylvania, 3800 Spruce Street, Philadelphia, Pennsylvania 19104-6045, U.S.A., ;