1. Department of Behavioral and Cognitive Biology, University of Vienna, Vienna, Austria
2. Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland
3. Department of Biology, University of Konstanz, Konstanz, Germany
4. Center for the Advanced Study of Collective Behaviour, University of Konstanz, Konstanz, Germany
5. Eulen- und Greifvogelstation Haringsee, Haringsee, Austria
6. Department of Psychology, Keio University, Tokyo, Japan
7. Faculty of Psychology, Education and Sports, University of Regensburg, Regensburg, Germany
8. Department of Linguistic and Cultural Evolution, Max Planck Institute for the Science of Human History, Jena, Germany
9. Department of Behavioral Sciences, Hokkaido University, Sapporo, Japan
10. School of Psychology, University of Auckland, Auckland, New Zealand
11. Max-Planck-Institute for Ornithology, Seewiesen, Germany
12. Department of Anthropology, University of Zurich, Zurich, Switzerland
13. Animal Ecology Group, Department of Biology, Utrecht University, Utrecht, Netherlands