About the Authors

George Sangster

george.sangster@nrm.se

Affiliations Department of Vertebrate Zoology, Swedish Museum of Natural History, Stockholm, Sweden, Department of Zoology, Stockholm University, Stockholm, Sweden

Ben F. King

Affiliation Ornithology Department, American Museum of Natural History, New York, New York, United States of America

Philippe Verbelen

Affiliation Independent Researcher, Gentbrugge, Belgium

Colin R. Trainor

Affiliation Independent Researcher, Perth, Western Australia, Australia

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Helped draft the manuscript: PV. Conceived and designed the experiments: GS. Performed the experiments: GS BFK. Analyzed the data: GS BFK. Contributed reagents/materials/analysis tools: GS BFK PV CRT. Wrote the paper: GS BFK.