This thesis focuses on the study of the spontaneous organisation of serial behaviour as a window on primate cognitive processes. The feasibility of a research program on non-human primates focused on such issues was tested by confronting capuchin monkeys (<I>Cebus apella</I>) with a set of search tasks. In a first group of experiments, the subjects were required to search serially an array of occulders presented with a WGTA, in order to retrieve a hidden object. Socially transmitted information allowed to infer the possible sites of the object, reducing the search space to a sub-set of all possible locations. The subjects showed a tendency towards searching in a principled way, either using the information given, or the spatial constraints afforded by the linear arrangement of the search space. However, some inadequacies were individuated in procedures and apparatus. Successively, tasks requiring the exhaustive exploration of a set of icons, presented on touch sensitive computer monitors, were employed. These tasks implicitly demand a serial and economic search, where reiterations on sites already explored should be avoided. The structure of the search space was manipulated so that either spatial strategies or categorisation schemes could be used as a memory aid to keep track of the moves already performed. Monkeys showed a spontaneous tendency to progressively reduce the number of redundant moves and spontaneously deployed spatial strategies when possible. This produced economic searches in sets of up to 9 locations.

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It has been proposed that the spectacular olfactory learning capabilities of the rat may prove useful in the development of rodent models of human amnesia. In particular, it has been suggested that rats show a 'primate-like' learning capacity when tested with olfactory (rather than visual or auditory) cues; and that this learning is sensitive to damage to brain stuctures considered critical in the human amnesic syndrome. The aim of this thesis is to evaluate and exploit these claims in the investigation of the neurobiology of rodent olfactory learning. In a series of experiments, an automated 'olfactory maze' is developed for the demonstration and measurement of rodent olfactory learning capacity, and parallels between rodent and primate learning capabilities are investigated. It is concluded that the suggestion that rats form 'primate-like' learning sets (and therefore learn complex abstract rules) when trained on a series of novel olfactory problems is unlikely to be correct. Investigation of the effects of hippocampal and dorsomedial thalamic nucleus (DMN) lesions on olfactory learning do not support the hypothesis that olfactory learning is sensitive to damage to the structures considered critical in human amnesia; hippocampal lesions are without effect, and DMN lesions appear to cause a perceptual, rather than cognitive, abnormality. Infusion of the N-methyl D-aspartate receptor in antagonist AP5, widely used as a tool to investigate the role of synaptic plasticity in learning, is also without effect. Hippocampally lesioned animals are, however, demonstrated to be impaired in a spatial reference memory task. On this basis, it is concluded that rodent olfactory learning does not constitute a useful model for the investigation of the biology of human amnesia.

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Part of the current model of the population of red grouse is that the food of the grouse chick affects their aggressive behaviour when adult. The aim of the present study was to test this experimentally using captive grouse. In 1971 and 1972 I reared a group of chicks on high (control group) and low (treated group) planes of nutrition. The treated chicks grew more slowly than the control but for longer period so that they become slightly smaller adults. It was shown that the protein limited the growth of 1972 treated chicks whereas it was uncertain which nutrient (or energy) was limiting in 1971. I measured several aspects of the aggressive behaviour of adult cocks. Individuals that were most aggressive behaviour in one situation tends to be so in others. They also had the largest combs and sang most frequently. Cocks of high dominance tended to be aggressive but this association was week. Cocks implanted with androgen became first more aggressive and only subsequently more dominant. Dominance abd aggressive are probably separate traits and the later may be determined by the circulating testosterone level. The low plane of nutrition does not change aggressiveness but lower dominance. The relationship between growth rate and dominance also applied to the individuals within the treated group. Some similar results have been found in studies of other captive vertebrates, mainly domestic and laboratory animals. Relative to the control captives, wild grouse chicks had a low level of protein in their diet and grew slowly so their dominance relationships may also have been affected by their planes of nutrition. Assuming that dominance reflects the ability of a cock to get a territory and aggressiveness, the size of the territory it would take, a hypothesis is presented: that a high plane of nutrition for grouse chicks enhances their ability to compete for territories and reduces the average size of territory that successful cocks attempt to take. This hypothesis applies only where grouse chicks have a plane of nutrition as high as that of the control captives (as, perhaps, on a fertilized moor or a moor overlying base-rich rock).

Differences in the breeding, survival, and social behaviour of individual red grouse are described for a population at low density during a fluctuation in breeding numbers. The aim was to identify aspects of the individual's upbringing which might be used for predicting his success or failure in joining the adult population. The basic premise was that differences in individual performance would be due to differences in the birds' nutrition. Three interrelated aspects of performance are considered: i) how and where the young cock competes for territory in autumn, in relation to his parentage and early development; ii) how the sur-vival and recruitment success of a brood compares with its nutritional background: and iii) whether the food in the parents' breeding territory is related to the size of that territory. Variation in the food was assessed by the percentage cover, N content, and height of the heather (Calluna vulgaris), which is the staple diet of red grouse. The histories of selected individual grouse were followed by radio-telemetry, beginning before nesting and extending for up to two years after. The main findings are: i) that young cock grouse from the same family returned during autumn to their parents' former territory, where they competed with one another and with their father for owner-ship of the parents' territory site: ii) that the success of the young cock in taking over the parents' territory was associated with his aggression, dominance, and early growth; iii) that the heather in the parents' territory was not used by the brood after hatching, and therefore had no direct effect on the individual cock's early development; iv) that the brood's early survival and growth were related to the heather in their parents' territory nonetheless, which suggests that its influence was indirect, probably via the quality of eggs laid by the hen; and v) that the heather available to the breed-ing hen was inversely correlated with the size of territory taken during the previous autumn by the cock. Other information is given on the selection of feeding sites by breeding hens, the behaviour of the brood towards predators, the behaviour of hen grouse during autumn, and the effectiveness of the radio-telemetry technique. A model is proposed which relates the individual's performance within any one year to the nutrition and performance of his family over successive generations. The conclusions about individual per-formance are discussed in terms of their possible adaptive significance, and suggestions are made for future research.

Increments on the internal shell, the gladius (or pen) of squids were used to investigate the growth histories of these pelagic marine animals both at the individuals level and at the population level. The gladius structure is unique because it is inextricably linked to the mantle length of the animals and provides a record of the growth of the animal at a resolution impossible to achieve with other methods. Since the technique is relatively new this thesis was concerned with the developments, validation and use of the technique for three squid species in the north-east Atlantic. The following areas were investigated: 1. The structure of the gladius and the dynamics of its deposition in hatchling and adult squid. 2. The development of gladius reading methods and the preliminary growth analysis for three species; <I>Loligo forbesi, Allotheuthis subulata</I> (Family Loliginidae) and <I>Todarodes sagittatus</I> (Family Ommastrephidae). 3. An estimate of chitin production (g m<SUP>-2</SUP> yr<SUP>-1</SUP>) from the gladius of squid for the seas west of Scotland. 4. Maintenance of captive squid (<I>Todarodes pacificus</I>) to determine the periodicity of increment formation using a chemical marker, the factors driving increment formation (temperature / feeding regime) and the effects of these factors on the overall growth of animals. 5. A hypothesis of increment formation is proposed. 6. The use of techniques to examine biology and ecology of the main UK fishery species, <I>Loligo forbesi</I>. The differences in growth histories between sexes, population cohorts and ecological phenomena such as multiple size modes at maturity were examined. In addition, the effects of maturity stage, reason and the presence of periodic components in the data were analysed.

The thesis reports the first demonstration of two-level hierarchical and linear organisation in six monkeys (Cebus apella). In behaviours elaborated over a four-year period, the hypothesis tested (McGonigle and Chalmers, 1992) was that progressive increases in task difficulty would be compensated by data reducing, economic, organisational structures. Novel touch-screen based procedures required the seriation and search of each item in a test set which, when increased in size, lead to geometrical increases in difficulty. Whilst on one scenario the subject should begin to fail as the task increases in difficulty, the performance of all subjects has shown progressive adaptation to such task requirements. This indicates an underlying dynamic process consistent with the operating hypothesis that cognitive organisation, both linear and hierarchical, are emergent responses motivated by a need for cognitive economy.

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No description available.