 In addition to his collaborative work with Bermúdez, Rosas developed an extensive work on the evolution of moral cognition and the cognitive roots of cooperation (2002, 2008a). In particular, he claims that altruism is selected both at the individual and at the group levels (2008b) and proposes a unified theory of human cooperation based on reciprocity (2010, 2012). Recently, with colleagues coming from philosophy and from science, he has contributed to the research on moral judgment with moral dilemmas (Rosas and Koenigs 2014; Rosas, Viciana, Caviedes, and Arciniegas 2019).