About the Authors

Patricia L.R. Brennan

To whom correspondence should be addressed. E-mail: patricia.brennan@yale.edu

Affiliations Department of Ecology and Evolutionary Biology, and Peabody Natural History Museum, Yale University, New Haven, Connecticut, United States of America, Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, United Kingdom

Richard O. Prum

Affiliation Department of Ecology and Evolutionary Biology, and Peabody Natural History Museum, Yale University, New Haven, Connecticut, United States of America

Kevin G. McCracken

Affiliation Institute of Arctic Biology, Department of Biology and Wildlife, and University of Alaska Museum, University of Alaska Fairbanks, Fairbanks, Alaska, United States of America

Michael D. Sorenson

Affiliation Department of Biology, Boston University, Boston, Massachusetts, United States of America

Robert E. Wilson

Affiliation Institute of Arctic Biology, Department of Biology and Wildlife, and University of Alaska Museum, University of Alaska Fairbanks, Fairbanks, Alaska, United States of America

Tim R. Birkhead

Affiliation Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, United Kingdom

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: PB. Performed the experiments: PB. Analyzed the data: RP PB. Contributed reagents/materials/analysis tools: MS RP TB PB KM RW. Wrote the paper: RP TB PB. Other: Made the original discovery of the structures with PLRB: TB. Discovered the original structures: PB.