About the Authors

Zihui Zhang

Affiliation College of Life Sciences, Capital Normal University, Beijing, China

Alan Feduccia

feduccia@bio.unc.edu

Affiliation Department of Biology, University of North Carolina, Chapel Hill, North Carolina, United States of America

Helen F. James

Affiliation Department of Vertebrate Zoology, MRC-116, National Museum of Natural History, Smithsonian Institution, Washington, D.C., United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: ZZ AJF. Performed the experiments: ZZ AJF. Analyzed the data: ZZ AJF HFJ. Contributed reagents/materials/analysis tools: ZZ AJF HFJ. Wrote the paper: ZZ AJF HFJ.