1. Negaunee Integrative Research Center, Field Museum of Natural History, 1400 South Lake Shore Drive, Chicago, Illinois 60605, U.S.A.,
2. Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, CAS Center for Excellence in Life and Paleoenvironment, Chinese Academy of Sciences, Beijing 100044, China
3. University of Chinese Academy of Sciences, Beijing 100049, China,
4. Geology and Geophysics Program, Missouri University of Science and Technology, Rolla, MO 65409, U.S.A.,