Theory of Mind - Non-human Theory of Mind

Non-human Theory of Mind

As the title of Premack and Woodruff's 1978 article "Does the chimpanzee have a theory of mind?" indicates, it is also important to ask if other animals besides humans have a genetic endowment and social environment that allows them to acquire a theory of mind in the same way that human children do. This is a contentious issue because of the problem of inferring from animal behavior the existence of thinking, of the existence of a concept of self or self-awareness, or of particular thoughts. One difficulty with non-human studies of ToM is the lack of sufficient numbers of naturalistic observation, giving insight into what the evolutionary pressures might be on a species' development of theory of mind.

Non-human research still has a major place in this field, however, and is especially useful in illuminating which nonverbal behaviors signify components of theory of mind, and in pointing to possible stepping points in the evolution of what many claim to be a uniquely human aspect of social cognition. While it is difficult to study human-like theory of mind and mental states in species whose potential mental states we have an incomplete understanding, researchers can focus on simpler components of more complex capabilities. For example, many researchers focus on animals' understanding of intention, gaze, perspective, or knowledge (or rather, what another being has seen). Call and Tomasello's study that looked at understanding of intention in orangutans, chimpanzees and children showed that all three species understood the difference between accidental and intentional acts. Part of the difficulty in this line of research is that observed phenomena can often be explained as simple stimulus-response learning, as it is in the nature of any theorizers of mind to have to extrapolate internal mental states from observable behavior. Recently, most non-human theory of mind research has focused on monkeys and great apes, who are of most interest in the study of the evolution of human social cognition. Other studies relevant to attributions theory of mind have been conducted using plovers and dogs, and have shown preliminary evidence of understanding attention—one precursor of theory of mind—in others.

There has been some controversy over the interpretation of evidence purporting to show theory of mind ability—or inability—in animals. Two examples serve as demonstration: first, Povinelli et al. (1990) presented chimpanzees with the choice of two experimenters from which to request food: one who had seen where food was hidden, and one who, by virtue of one of a variety of mechanisms (having a bucket or bag over his head; a blindfold over his eyes; or being turned away from the baiting) does not know, and can only guess. They found that the animals failed in most cases to differentially request food from the "knower." By contrast, Hare, Call, and Tomasello (2001) found that subordinate chimpanzees were able to use the knowledge state of dominant rival chimpanzees to determine which container of hidden food they approached. William Field and Sue Savage-Rumbaugh have no doubt that bonobos have developed ToM and cite their communications with a well known captive bonobo, Kanzi, as evidence.