Date of Award


Degree Type


Degree Name

Doctor of Philosophy (PhD)

Graduate Group


First Advisor

Michael Weisberg


Humans often have difficulty accurately evaluating the cognitive capacities of nonhuman animals. We have been biased in assuming human cognitive superiority and that the cognitive capacities of other species ought to be measured by human standards of intelligence. Such anthropocentric biases distort our scientific thinking about cognition and our relationships to animals and their habitats, as we carelessly disrupt ecosystems and endanger animals. Anthropocentric biases may lead humans to dismiss findings of nonhuman intelligence, especially in animals not closely related to us. Empirical research shows that nonhuman and non-primate animals engage in cognitively sophisticated behaviors. To counter our distorted perspective of nonhuman animals, this dissertation urges greater consideration of the cognitive sophistication of nonhumans, which can provide insight into the origins of our cognitive capacities. In particular, I consider the research of Irene Pepperberg, who trained parrots to communicate referentially using English words. Through an analysis of empirical research, including Pepperberg’s research with Alex the parrot, I propose a four-dimensional model describing the conditions under which such animals can actualize their capacity for referential communication (Chapter 2). The degree to which Alex the parrot became an active communicator, not only by learning to use existing English words but also by originating meaning by coining a new word, demonstrates the power of his ability to learn under favorable training conditions (Chapter 3). To think accurately about the cognitive capacities of organisms who are quite different from us, we need to focus on functional relations rather than on superficial characteristics. I argue for a functional analytical framework that allows us to compare similarly complex behaviours between different species and infer similar underlying cognitive mechanisms (Chapter 4). That a parrot learned to use words within a training context suggests that non-primate animals have the capacity to learn proto-linguistic forms of communication even when they do not evince such behavior in nature. In emphasizing the importance of social-ecological context, training and motivation, this dissertation undermines traditional anthropocentric assumptions about the inferiority of the cognitive capacities of non-primates.