1. Department of Comparative Language Science University of Zürich Zürich Switzerland
2. Budongo Conservation Field Station Masindi Uganda
3. Center for the Interdisciplinary Study of Language Evolution (ISLE) University of Zürich Zürich Switzerland
4. Department of Comparative Cognition, Institute of Biology University of Neuchâtel Neuchâtel Switzerland
5. Center for Social Learning and Cognitive Evolution, School of Psychology and Neuroscience University of St. Andrews St. Andrews UK
6. Max Planck Institute for Evolutionary Anthropology Leipzig Germany
7. Department of Psychology University of Warwick Warwick UK
8. Division of Psychology, Faculty of Natural Sciences University of Stirling Stirling UK