Jorg Massen received his Master degree in Animal Behaviour Sciences at Utrecht University, The Netherlands. For his master thesis he did extensive fieldwork in the peat-swamp forests of Borneo, studying the development of feeding competence of immature wild orangutans. During his subsequent work as Ph.D.-candidate, again at Utrecht University, he furthered his primatological work, studying friendship and its underlying mechanisms in two species of macaques, using both observational and experimental techniques. After receiving his Ph.D. in 2010, he was awarded a research grant from the Lucy Burgers Foundation for Comparative Research allowing him to do post-doctoral research at the chimpanzee colony of Burgers’ Zoo, Arnhem, the Netherlands. There he furthered his research on the pro-social preferences of animals and started his studies of animal personality using group based experiments. In 2011 he was awarded a Lise-Meitner grant form the Austrian Science Fund to study cooperation and it’s necessary cognition in ravens, enabling him to add to the primates another fascinating family of intelligent animals; the corvids. Accordingly, he is now a post-doctoral research fellow at the corvid-lab of the department of Cognitive Biology at the University of Vienna.