1. Centre for Social Learning and Cognitive Evolution, School of Psychology and Neuroscience, University of St Andrews, South Street, St Andrews KY16 9JP, UK
2. School of Life Sciences, Heriot-Watt University, Edinburgh EH14 4AS, UK
3. Institute of Cognitive and Evolutionary Anthropology, University of Oxford, Oxford OX2 6PN, UK
4. Brain, Belief, and Behavior Lab; Centre for Psychology, Behaviour, and Achievement, Coventry University, Coventry CV1 5FB, UK
5. College of Life and Environmental Sciences, University of Exeter, Exeter TR10 9EZ, UK
6. National Center for Chimpanzee Care, Michale E. Keeling Center for Comparative Medicine and Research, The University of Texas MD Anderson Cancer Center, Bastrop, TX, USA
7. Departments of Psychology and Philosophy, Neuroscience, Institute and Language Research Center, Georgia State University, Atlanta, GA, USA