A multi-facetted approach to investigating theory of mind in corvids
Theory of mind refers to the ability to attribute mental states to others and to predict their behaviour based on inferences about their mental states, for example their perception, desires, or beliefs. Forty years ago, research on theory of mind originated from the question of whether or not chimpanzees (Pan troglodytes) have a theory of mind, a question that – after all this time – is still debated. In the present thesis, I investigate theory of mind and its precursors in birds of the crow family, specifically Eurasian jays (Garrulus glandarius), California scrub-jays (Aphelocoma californica), and carrion crows (Corvus corone corone). Corvids have been reported to possess theory of mind-like abilities. This qualification reflects the fact that most research on theory of mind in these birds has revolved around the ability to respond to perceptual and desire states of conspecifics, and so far has not produced evidence for or against an ability to also respond to others’ beliefs. Further, it is unclear which mechanisms could be the basis of corvids’ abilities. Thus, there are two open questions in regard to corvid theory of mind my thesis aims to address. To address these questions, first, I investigated the ability of Eurasian jays to respond to the false belief of a conspecific in a caching paradigm, where the knowledge of a conspecific observer about the accessibility of two caching sites was manipulated (Chapter 2). In Chapter 3 I explore which behavioural cues might present the basis of the jays’ ability to respond to the desire of a conspecific in a caching context. In Chapter 4, I report a study on biological motion perception in scrub-jays, a phenomenon suggested to be crucial for the detection of social agents. In Chapter 5, I assess scrub-jays’ sensitivity to gaze of a human and a conspecific. Finally, in Chapter 6, I report a study investigating the face inversion effect in carrion crows, an effect that is indicative of a ‘special’ relevance of faces. I conclude by discussing how the presented studies could help us inform our understanding of corvid theory of mind-like abilities.
Theory of mind, corvids, social cognition, precursors
Networked Digital Library of Theses and Dissertations