The Evolutionary Origins of Representational and Motivational Hallmarks of Human Social Cognition

Abstract

Human social cognition is supported both by our ability to represent others’ mental states and our propensity to share these mental states with others in collaborative activities. As adult humans, we recognize that the content of other minds often differs from that of our own, but we are also deeply motivated to share common beliefs and desires with others. This dissertation explores the evolutionary origins of these representational and motivational hallmarks of human social cognition via two complementary lines of research: the first explores whether non-human primates represent others’ knowledge and ignorance states in the same way as humans, and the second explores whether domestic dogs show a similar propensity as humans to form shared intentions with social partners in joint activities. Chapters 1 and 2 provide background on my research questions, my approach to testing them, and a brief review of the relevant literature. In Chapter 3, I discuss the implications of my findings and suggest promising directions for future research. Each of the three articles that compose the main body of this dissertation are presented in the appendices. In Appendix A, I show that non-human primates appear to represent others’ knowledge and ignorance states via more heuristic-like mechanisms than are evident in human meta-representation. Relatedly, Appendix B explores the representational content of knowledge-like attributions in non-human primates by elucidating conditions that cause these attributions to break down. In Appendix C, I turn to motivational questions about mental state sharing, showing that domestic dogs exhibit a key behavioral marker of joint intentionality – an ability often argued to support uniquely human ways of forming shared goals and commitments with others. Collectively, this work supports the idea that humans may have evolved unique ways of representing the contents of other minds, but that our propensity to jointly share experiences with others may be more widely evident across even distantly-related species.