About the Authors

Charles G. Nathanson
Department of Economics, Harvard University, Cambridge, Massachusetts, United States of America

Corina E. Tarnita, Martin A. Nowak
Program for Evolutionary Dynamics, Department of Mathematics, Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, United States of America

Corresponding Author

corina@math.harvard.edu

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Wrote the paper: CGN CET MAN. Conducted the research: CET, CGN, MAN.