Experimental investigation of social learning in domestic animals and non-human primates.
Thesis or dissertation
University of Exeter
Imitation is considered to be an efficient method of conveying information between individuals. It is believed to be among the least common and most complex forms of animal learning. After almost a century of studying social learning in animals, scientists still have not been able to give a clear answer to the question “Do animals imitate?”. Although there have been some studies that have shown certain species under certain conditions unequivocally imitate (e.g. Zentall, et al., 1996), these studies have not been successfully replicated in a wide range of species. This thesis expands the social learning literature extending the range of settings and species in which it has been studied and by drawing links to the field of behaviour analysis. Four of the current studies used versions of the two-action method to look for imitative learning in both non- human primates and domesticated animals. In this methodology an observer watches a demonstrator manipulate an apparatus with two different parts of their body. Using two different parts of the body and not two different manipulations lets researchers determine if the individual is learning by observation or just learning about changes in the state of the environment. This methodology is the only one that can distinguish local enhancement (learning only to attend to the location of the demonstrator), or stimulus enhancement (learning only to attend to the stimulus which the demonstrator interacts with) from “true” imitation (Campbell, Heyes, and Goldsmith, 1999). One of the current studies used the “do as I do” methodology. In this method a subject is trained to match a few gestures of the demonstrator for reinforcement (i.e. the demonstrator raises her/his hand and the subject raises his/her hand) on the verbal command of “Do this” or “Do it”. After the subject reaches criterion on the trained behaviours a novel behaviour is added that has not been trained to see if the subject will spontaneously imitate the behaviour. Successfully copying a novel demonstration is taken as evidence of understanding the rule needed for imitative performance. This methodology is popular because it not only can distinguish between imitation and the other forms of social learning, but it can also show the subjects’ ability to generalize this type of learning. The overall results show very little imitative learning occurring in the various groups of animals studied. The low rate of imitation may not be surprising. For just over 100 years psychologists have been studying social learning and in that time only a handful of researchers have been able to show clear evidence of an animal’s ability to imitate the actions of a demonstrator. These results suggest that, though imitative learning may be important in the lives of a few species, or in the acquisition of particular behaviour, it is unlikely that it plays an essential role in the acquisition of behaviour in general, especially behaviour through which animals directly manipulate their environment.
PhD in Psychology