Commentary What are we learning from teaching? Richard W. Byrne a, 1 , Lisa G. Rapaport b, * a Centre for Research in Social Learning and Cognitive Evolution, School of Psychology, University of St Andrews b Department of Biological Sciences, Clemson University article info Article history: Received 17 May 2011 Initial acceptance 8 July 2011 Final acceptance 9 August 2011 Available online 23 September 2011 MS. number: AS-11-00400R Keywords: evolution of mind functional definition intention social learning teaching A man belonging to the Aché tribe sits down on a long log in the clearing of his forest camp in a Paraguayan Forest Reserve to make a bow. He selects that particular log because it affords a place for another person to sit side-by-side with him. He calls to his son as he begins to work, and his son comes to sit down next to him, watching. Carving a notch into the top of the wooden shaft, the man does not speak but does shift position from time to time so that his son can better observe the process. He methodically wraps the sinew string around the notch in the bow and covers it with a sticky resin. By late afternoon, the father has created a new bow and the son has learned something: the steps involved in making a tradi- tional hunting weapon. Children in a classroom are learning to write in cursive. The teacher projects the cursive letter models on a Promethean whiteboard and demonstrates how the letters are formed. The students then begin to practise copying the models on their own. One child is having particular difficulty. The teacher walks over, cups the pupil’s hand in hers and moulds his actions to the correct form. She only helps this one student; she never had to do so with any of her students during the previous year. These and similar interactions take place so frequently across the globe as to be unremarkable to the average person. Yet their significance with regard to the evolution and spread of human technological and social culture cannot be overestimated. Our species-wide proclivity to rely on social learning, in particular imitation and teaching, is thought to have first led to the emergence of culture in our hominin ancestors and to support cultural trans- mission up to the present day (Boyd & Richerson 1996). Humans have sophisticated cognitive powers that both allow us to imitate a complicated sequence of actions and, in addition, to understand the way each of those actions works towards the final goal, so that the sequence may not only be copied but also improved upon (Boyd & Richerson 1996; Byrne 2006). Few other animals are thought to have these capabilities. What is more, we humans have a psychology that drives us to share our intentions, a psychology that allows us to collaborate with others to an unusual degree (Tomasello et al. 2005). This motivation to share information and to peer into the minds of others has undoubtedly favoured our penchant for social learning, especially teaching (Burkart et al. 2009; van Schaik & Burkart 2010). It is one thing for an animal to gain information from another more informed conspecific, as the more knowledgeable individual goes about his or her normal activities. Social learning of various types is common throughout the animal kingdom. It is quite another for a knowledgeable individual to alter his or her behaviour in such a way as to actively help another to learn what the knowledgeable individual knows: that is, to teach. * Correspondence: L. G. Rapaport, Department of Biological Sciences, 132 Long Hall, Clemson University, Clemson, SC 29634, U.S.A. E-mail address: Lrapapo@clemson.edu (L. G. Rapaport). 1 R. W. Byrne is at the Centre for Research in Social Learning and Cognitive Evolution, School of Psychology, University of St Andrews, U.K. Contents lists available at SciVerse ScienceDirect Animal Behaviour journal homepage: www.elsevier.com/locate/anbehav 0003-3472/$38.00 Ó 2011 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.anbehav.2011.08.018 Animal Behaviour 82 (2011) 1207e1211