About the Authors

James J. Cai

Affiliation Department of Biology, Stanford University, Stanford, California, United States of America

J. Michael Macpherson

Affiliation Department of Biology, Stanford University, Stanford, California, United States of America

Guy Sella

These authors are joint senior authors on this work.

Affiliation Department of Evolution, Systematics, and Ecology, The Hebrew University of Jerusalem, Givat Ram, Jerusalem, Israel

Dmitri A. Petrov

dpetrov@stanford.edu

These authors are joint senior authors on this work.

Affiliation Department of Biology, Stanford University, Stanford, California, United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: JJC JMM GS DAP. Performed the experiments: JJC. Analyzed the data: JJC GS DAP. Contributed reagents/materials/analysis tools: JJC JMM GS DAP. Wrote the paper: JJC DAP.