Human culture has been proposed to uniquely exhibit a ‘ratchet effect’, with beneficial modifications being made to cultural traits over many generations. This is widely thought to have allowed an accumulation of technology and knowledge over time, and to be of central importance to the remarkable ecological and demographic success of humans. Whilst many researchers argue that the roots of human culture lie in social learning, a process widespread in nature, the exact cognitive capacities that set humans apart are not known. To provide a comparative assessment of nine separate hypotheses regarding different social and cognitive factors that may underlie a capacity for cumulative culture, in this thesis a cumulative puzzlebox was presented to three species. Groups of capuchins, chimpanzees and children were provided with the opportunity to solve the puzzlebox to three sequential levels to retrieve rewards of increasing desirability. Higher level solutions spread only in the children. Evidence was found for the occurrence of teaching, imitation, complex communication and prosociality in groups of children, but not in groups of capuchins and chimpanzees. Furthermore, these processes were positively correlated with the performance of individuals within the groups of children which was the only species to show evidence of cumulative cultural learning. Five further hypotheses focussed on alternative social and cognitive factors were not supported by the evidence from this experiment.

This study examined object permanence in Sumatran orangutans (Pongo abelii), Western lowland gorillas (Gorilla gorilla gorilla), and black-and-white-ruffed lemurs (Varecia variegata) at Zoo Atlanta. A literature review reveals two main issues with object permanence research in non-human primates. One of the issues is that it is difficult to make valid comparisons between different species because very few studies have been conducted using appropriate controls. Thus, one of the goals of this study was to conduct control trials for all tasks in the traditional object permanence test battery, in order to reliably assess and compare performance in the species under study. The second issue is concerned with the finding that all of the non-human primate species tested so far have failed one of the more difficult tasks in the test battery, namely the non-adjacent double invisible displacement task. It has been hypothesized that this performance limitation is a result of the manner in which the task is presented. Thus, the second goal of this study was to modify the existing methodology and present the task to gorillas and orangutans in locomotive space to see if performance improves. This is the first study to present this task to non-human primate species in locomotive space. This study found that orangutans were the only species to reliably pass most tasks in the traditional object permanence test battery. Black-and-white ruffed lemurs failed most visible and invisible displacement tasks. Owing to the small sample size of gorillas in this study, further research is required before any firm conclusions can be made about the ability of this species to solve visible and invisible displacement tasks in the traditional object permanence test battery. Presenting the boxes in locomotive space to gorillas and orangutans did not improve performance on the non-adjacent double invisible displacement task. Further research is required to resolve the question of whether this performance limitation is a result of the manner in which the task was presented.

Thesis (M.Soc.Sc. Psychology)--University of Waikato, 2007. / Title from PDF cover (viewed April 8, 2008) Includes bibliographical references (p. 70-76)

The aim of this thesis is to examine the cognitive processes of social learning from the bottom up. In the field of comparative psychology, an overemphasis on understanding complex cognitive processes in nonhuman animals (e.g. empathy, imitation), may be detrimental to the study of simpler mechanisms. In this thesis, I report five studies of simple cognitive processes related to social learning. A series of experiments with human children and capuchin monkeys (Sapajus sp.), examined action imitation and identified a possible role for associative learning in the development of this ability. An analysis of observational data from captive capuchins explored a number of lesser-studied social learning phenomena, including behavioural synchrony, the neighbour effect, and group-size effects. The results of this study emphasise the importance of exploring behaviour at a number of levels to appreciate the dynamic nature of social influence. Two final experiments examined social contagion in capuchin monkeys, and highlight the importance of describing the relationship between behaviour and emotion to properly understand more complex social cognition. Together, these studies demonstrate how approaching human and nonhuman behaviour from the bottom up, as well as from the top down, can contribute to a better comparative science of social learning.

In the wild, a variety of inter-group behavioural differences have been reported for chimpanzees (Pan troglodytes) and it has been suggested that these may have resulted from social learning. To determine whether chimpanzees show the necessary propensity for social learning, groups of captive chimpanzees were tested in a series of experiments involving the use of two-action and bidirectional apparatuses. For comparison, and to shed light on any contrasts between our own and chimpanzee learning strategies, similar tests were also conducted with children (Homo sapiens) to ascertain the nature of their observational learning when watching conspecifics. Through the use of open diffusion and diffusion chain techniques, it was shown that both species learnt how to operate different foraging devices from observing an expert conspecific and this learning was strong enough for the generation of behavioural traditions which passed along multiple test ‘generations’. Additionally, ghost conditions were used to distinguish imitative and emulative learning by both species. With one of the two test devices used (the Slide-box) the first evidence for emulation learning by chimpanzees, through the use of a ghost condition, was shown. Children in this condition also showed apparent emulation; a contrast to previous research which has concluded that children tend to rely on imitation. Additionally, to test its potential for use in future social learning experiments, the ability of chimpanzees to learn from video-footage of an unknown conspecific was tested. It was found that the chimpanzees not only learnt how to operate two devices from observing this footage but also used the same alternative method used by the model chimpanzee.