1. Artificial Intelligence Laboratory, Vrije Universiteit Brussel, Pleinlaan 2, Brussels 1050, Belgium
2. Research Centre in Evolutionary Anthropology and Palaeoecology, School of Natural Sciences & Psychology, Liverpool John Moores University, Byrom Street, Liverpool, UK
3. Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Science Park 904, Amsterdam 1098 XH, The Netherlands
4. Pongo Foundation, Papenhoeflaan 91, Oudewater 3421XN, The Netherlands