1. Department of Cognitive Biology, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria.
2. Haidlhof Research Station, University of Vienna/University of Veterinary Medicine Vienna, Bad Vöslau, Austria.
3. Artificial Intelligence Laboratory, Vrije Universiteit Brussel, Pleinlaan 2, 1050 Brussels, Belgium.
4. Princeton Neuroscience Institute, Princeton University, Princeton, NJ 08544, USA.
5. Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA.
6. Department of Psychology, Princeton University, Princeton, NJ 08544, USA.