About the Authors

Claudia A. F. Wascher

claudia.wascher@klf.ac.at

Affiliations Konrad Lorenz Forschungsstelle, Core Facility University of Vienna, Gruenau, Austria, Department of Behavioural Biology, University of Vienna, Vienna, Austria, Department of Cognitive Biology, University of Vienna, Vienna, Austria

Thomas Bugnyar

Affiliations Konrad Lorenz Forschungsstelle, Core Facility University of Vienna, Gruenau, Austria, Department of Cognitive Biology, University of Vienna, Vienna, Austria

Competing Interests

The authors hereby declare that funding received by a commercial source (L′Oreal) does not alter their adherence to all the PLOS ONE policies on sharing data and materials.

Author Contributions

Conceived and designed the experiments: CAFW TB. Performed the experiments: CAFW. Analyzed the data: CAFW. Wrote the paper: CAFW TB.