About the Authors

Joseph W. Brown

Affiliation Museum of Zoology and Department of Ecology & Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, United States of America

Ulf Sorhannus


Affiliation Department of Biology & Health Services, Edinboro University of Pennsylvania, Edinboro, Pennsylvania, United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: US. Analyzed the data: JWB US. Wrote the paper: JWB US.