About the Authors

Erica van de Waal

erica.vandewaal@unine.ch

Affiliations Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland, Applied Behavioural Ecology and Ecosystem Research Unit, University of South Africa, Florida, South Africa, School of Psychology, University of St Andrews, St Andrews, United Kingdom

Michael Krützen

Affiliation Evolutionary Genetics Group, Anthropological Institute and Museum, University of Zürich, Zürich, Switzerland

Josephine Hula

Affiliations Applied Behavioural Ecology and Ecosystem Research Unit, University of South Africa, Florida, South Africa, Evolutionary Genetics Group, Anthropological Institute and Museum, University of Zürich, Zürich, Switzerland

Jérôme Goudet

Affiliation Department of Ecology and Evolution, University of Lausanne, Lausanne, Switzerland

Redouan Bshary

Affiliations Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland, Applied Behavioural Ecology and Ecosystem Research Unit, University of South Africa, Florida, South Africa

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: EW RB. Performed the experiments: EW JH. Analyzed the data: EW MK JH JG RB. Wrote the paper: EW MK JG RB.