Abstract: There has been relatively little research on the psychological mechanisms of social learning. This may be due, in part, to the practice of distinguishing categories of social learning in relation to ill-defined mechanisms (Davis, 1973; Galef, 1988). This practice both makes it difficult to identify empirically examples of different types of social learning, and gives the false impression that the mechanisms responsible for social learning are clearly understood. It has been proposed that social learning phenomena be subsumed within the categorization scheme currently used by investigators of asocial learning. This scheme distinguishes categories of learning according to observable conditions, namely, the type of experience that gives rise to a change in an animal (single stimulus vs. stimulus-stimulus relationship vs. response-reinforcer relationship), and the type of behaviour in which this change is detected (response evocation vs. learnability) (Rescorla, 1988). Specifically, three alignments have been proposed: (i) stimulus enhancement with single stimulus learning, (ii) observational conditioning with stimulus-stimulus learning, or Pavlovian conditioning, and (iii) observational learning with response-reinforcer learning, or instrumental conditioning. If, as the proposed alignments suggest, the conditions of social and asocial learning are the same, there is some reason to believe that the mechanisms underlying the two sets of phenomena are also the same. This is so if one makes the relatively uncontroversial assumption that phenomena which occur under similar conditions tend to be controlled by similar mechanisms. However, the proposed alignments are intended to be a set of hypotheses, rather than conclusions, about the mechanisms of social learning; as a basis for further research in which animal learning theory is applied to social learning. A concerted attempt to apply animal learning theory to social learning, to find out whether the same mechanisms are responsible for social and asocial learning, could lead both to refinements of the general theory, and to a better understanding of the mechanisms of social learning. There are precedents for these positive developments in research applying animal learning theory to food aversion learning (e.g. Domjan, 1983; Rozin & Schull, 1988) and imprinting (e.g. Bolhuis, de Vox & Kruit, 1990; Hollis, ten Cate & Bateson, 1991). Like social learning, these phenomena almost certainly play distinctive roles in the antogeny of adaptive behaviour, and they are customarily regarded as 'special kinds' of learning (Shettleworth, 1993).(ABSTRACT TRUNCATED AT 400 WORDS)

Abstract: We tested for social learning and imitation in common marmosets using an artificial foraging task and trained conspecific demonstrators. We trained a demonstrator marmoset to open an artificial fruit, providing a full demonstration of the task to be learned. Another marmoset provided a partial demonstration, controlling for stimulus enhancement effects, by eating food from the outside of the apparatus. We thus compared three observer groups, each consisting of four animals: those that received the full demonstration, those that received the partial demonstration, and a control group that saw no demonstration prior to testing. Although none of the observer marmosets succeeded in opening the artificial fruit during the test periods, there were clear effects of demonstration type. Those that saw the full demonstration manipulated the apparatus more overall, whereas those from the control group manipulated it the least of the three groups. Those from the full-demonstration group also contacted the particular parts of the artificial fruit that they had seen touched (localised stimulus enhancement) to a greater extent than the other two groups. There was also an interaction between the number of hand and mouth touches made to the artificial fruit for the full- and partial-demonstration groups. Whether or not these data represent evidence for imitation is discussed. We also propose that the clear differences between the groups suggest that social learning mechanisms provide real benefits to these animals in terms of developing novel food-processing skills analogous to the one presented here.

Abstract: We carried out a questionnaire survey of the caretakers, using 86 riding horses kept in the Equestrian Park, Tokyo (Japan Racing Association). The questionnaire survey used a 5-point scale and a 3-point scale to assess several caretakers' impressions of each horse's temperament, on the basis of the norm and the horse's tendencies in ordinary care and daily training. Factor analysis of the temperament scores obtained with the 5-point scale questionnaire revealed three mutually independent factors that we named “anxiety”, “novelty seeking” and “understanding”. In order to verify the reliability of this questionnaire survey, a balloon reactivity test was conducted using the same horses. Each horse was introduced into an unfamiliar indoor arena (7 mx12.5 mx3 m) in the center of which two balloons slowly revolved. The horses' responses were assessed by recording changes in their behavior and heart rate (HR) during the 5 min experimental period. By comparing the questionnaire survey and the balloon reactivity test, it was found that the horses evaluated as highly anxious by the caretakers tended to show greater HR increases and defecate more often during exposure to the balloon stimuli than did the other horses. Additionally, the horses assessed by caretakers to have problems with ordinary care and/or training showed greater increases of HR and frequency of defecation in the balloon reactivity test, and the horses assessed as having `a long adaptation time to unfamiliar objects' were found to be unwilling to touch the balloons. Thus, the horses' behavior during the balloon reactivity test was highly consistent with their temperament as determined by the questionnaire. These results suggest that the questionnaire survey would be an effective means to assess equine temperamental traits, especially those related to anxiety.

Abstract: Classically, biologists have considered adaptation of behavioural characteristics in terms of long-term functional benefits to the individual, such as survival or reproductive fitness. In captive species, including the domestic horse, this level of explanation is limited, as for the most part, horses are housed in conditions that differ markedly from those in which they evolved. In addition, an individual horse's reproductive fitness is largely determined by man rather than its own behavioural strategies. Perhaps for reasons of this kind, explanations of behavioural adaptation to environmental challenges by domestic animals, including the capacity to learn new responses to these challenges, tend to concentrate on the proximate causes of behaviour. However, understanding the original function of these adaptive responses can help us explain why animals perform apparently novel or functionless activities in certain housing conditions and may help us to appreciate what the animal welfare implications might be. This paper reviews the behavioural adaptation of the domestic horse to captivity and discusses how apparently abnormal behaviour may not only provide a useful practical indicator of specific environmental deficiencies but may also serve the animal as an adaptive response to these deficiencies in an “abnormal” environment.