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Group formation is a fundamental step in the evolution of cooperation, yet there are few models of this process in social animals, and even fewer empirical tests. The prolonged nest initiation phase in temperate paper wasps provides a valuable opportunity to study group formation. Data were obtained for 180 groups of females collected from a large population of Polistes dominulus in two sites in south-western Spain. Foundresses on early nests were more closely related then females in winter aggregations or in stable groups (just before workers emerged). Most stable groups (£ 85 %) had one or more females that were unrelated (or distantly related) to the remaining members of the group. Mean wasp size did not markedly change during the different stages of the nesting cycle. Only 15 % of all foundresses had one or more clypeal marks. Wasps with marks were more common at the end of the nest foundation period than at early nests suggesting that these wasps may be adopting a "sit and wait" strategy. Foundresses that hibernated in the same aggregation were more likely to start a nest together. Changes in group composition were likely to be caused by the disappearance of foundresses (death) and the frequent arrival of joiners to established groups. Within-group relatedness was not affected by the arrival of late joiners, but was negatively correlated with the date that nests were initiated. Only 16 % of all successfully marked wasps visited more than one nest. These wasps tended to move to nests with higher within-group relatedeness and less clypeal marks variability than their original group, but not necessarily a higher number of their own relatives. Dominance hierarchies were experimentally inferred for 53 nests. Rank was negatively correlated with the number of full-sisters foundresses an individual had in its group. Highly-ranked wasps (rank 1 and 2) were less likely to share a nest with their full-sisters than wasps of lower rank, but an individual's rank was not affected by whether its full-sisters had a higher or lower position than it in the dominance hierarchy. Rank was also correlated with the size of clypeal marks, but only one foundress had a mark on 15 nests out of the 20 nests where wasp with marks were present (out of 53).

The aim of this thesis is to investigate a methodology for studying perceptual systems by building artifical ones. It is proposed that useful results can be obtained from detailed robotic modelling of specific sensorimotor mechanisms in lower animals. By looking at the sensory control of behaviour on simple biological organisms, and in working robots, it is argued that proper appreciation of the physical interaction of the system with the environment and the task is essential for discovering how perceptual mechanisms function. Although links to biology, and concern with perceptual competence, are fields of growing interest in Artificial Intelligence, much of the current research fails to adequately address these issues, as the model systems being built do not represent real sensorimotor problems. By analyzing what is required for a model of a system to contribute to explaining that system, a particular approach to modelling perceptual systems is suggested. This involves choosing an appropriate target system to model, building a system that validly represents the target with respect to a particular hypothesis, and properly evaluating the behaviour of the model system to draw conclusions about the target. The viability and potential contribution of this approach is demonstrated in the design, implementation and evaluation of a mobile robot model of a hypothesised mechanism for phonotaxis in the cricket. The result is a robot that successfully locates a specific sound source under a variety of conditions, with a range of behaviour that resembles the cricket in many ways. This provides some support for the hypothesis that the neural mechanism for phonotaxis in crickets does not involve separate processing for recognition and location of the signal, as is generally supposed. It also shows the importance of understanding the physical interaction of the system's structure with its environment in devising and implementing perceptual systems. Both these results vindicate the proposed methodology.

This thesis presents a functional analysis of some multi-bar linkage mechanisms in animals. In particular it investigates the effect of multi-bar linkage mechanisms on the locomotion efficiency of animals. Three case studies are presented. The first case study involves modeling the deployment of the jaw mechanism in the sling jaw wrasse. Numerical modeling of the energy required to move in water shows that the jaw mechanism can signifIcantly reduce the energy cost of locomotion. The second case study involves mode ling the effect of the pantograph mechanism in bird wings on the inertial power required for flight. Energy modeling shows that the pantograph mechanism has a small but significant advantageous effect on locomotion by reducing the inertia of wings. The energy modeling also shows that significant aerodynamic braking occurs during flapping. The third case study involves modeling the benefIts of the linkage mechanism inside insect wings. This study shows there are significant benefits in having 4-bar mechanisms because the mechanisms provide compliance that enables elastic5-storage to take place during wing flapping. The case studies show that linkage mechanisms enable complex mechanical functions to take place that lead to signifIcant energy savings. A common factor in all the case studies was that the actuator is optimally located where mass and space is not at a premium. The potential for biomimicry is discussed for each case study. The sling wrasse jaw has potential for harvesting and cleaning applications. The bird pantograph mechanism and insect wing mechanism has potential for micro air vehicle design and robotics design. There are similarities between multi-bar mechanisms in engineering and nature in terms of types of mechanism. However, there are significant differences in the detail implementation. Engineering mechanisms have pinned joints whereas in nature there are pivot points. Engineering mechanisms tend to be planar whereas in nature they are 3-dimensional. Engineering mechanisms tend to be fully constrained whereas nature's mechanisms tend to be under constrained.

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This thesis describes a series of studies designed to examine Triturus oviposition behaviour using a detailed approach. Specifically, two main lines of investigation were examined; the impact of egg-laying substrate material and of female body size. Triturus oviposition is a complex and unusual behaviour in which eggs are wrapped individually in the submerged leaves of aquatic plants. However, despite the apparently sequential and selective nature of this process, its likely significant cost to females and its implications for reproductive success, detailed behavioural information is lacking. A series of observational studies were set up to address this existing gap in knowledge. First, and fundamental to all subsequent comparisons, a detailed quantifiable ethogram of oviposition behaviour was developed. This revealed that deposition occurs as part of a repeated sequence of distinct behavioural elements common to all three UK newt species. From the ethogram, a series of oviposition measures were derived to facilitate all subsequent behavioural comparisons. In the first main investigative thread, the effects of substrate on oviposition were examined by comparing the behaviour of T. vulgaris females given a typical host substrate, Apium nodiflorum, with the behaviour of those given one of two more unusual substrates, Crassula helmsii or polythene strips (selected for their likely physical and chemical diversity). Key elements of the behavioural sequence, egg deposition rates and measures related to embryonic development were found to differ significantly between the substrates. On presenting the same materials to females of T. helveticus and T. cristatus, marked differences were also clearly identified. Moreover, whilst certain components clearly varied in response to different substrates, others appeared to follow a more fixed behaviour pattern. The impact of female body size on oviposition, the second main line of investigation, was initially considered by comparing the behaviour patterns generated by the three newt species in the substrate-focused experiments. These comparisons showed that there were inconsistencies in certain aspects of the process across all three species. Thus, whilst differences between overtly differently sized newts could possibly be accounted for by body size variation, it was not clear whether the subtle size disparity between T. vulgaris and T. helveticus explained the differences between these two species. A more explicit assessment of female body size examined the oviposition behaviour of the two small-bodied newts further. Correlation analyses revealed that body size impacted differently on certain elements of the process within each newt species. A more novel size-matched approach showed that small differences in body size, although these may have accounted for some of the variation, did not explain all of it. A possible underlying mechanism based on morphological differences between the species was proposed. The work in this thesis shows that both substrate material and female body size impact on the egg-laying process. It highlights the importance of collecting oviposition behaviour detail in a systematic way across a group of closely related species and clearly contributes to the existing Triturus oviposition literature. Moreover, the findings, aside from their intrinsic scientific value, have potentially wider-reaching implications for the ecology and phylogeny of these species, as well as possible conservation applications.

There is a growing need for non-human primate populations in captivity to be managed using techniques based on scientific principles, so as to be able to maintain self-sustaining populations and also, if need be, successfully reintroduce these populations into their wild habitats. It is thus recognised that captive primate groups should be housed in environments in which their welfare is not compromised where they can exhibit most, if not all, of their natural social and behavioural characteristics. In order to design and maintain ideal captive environments for primates, it is important to incorporate applied animal behaviour and welfare research in the mandateo f conservationb reedingp rogrammesin zoos. In this study, the behaviour of captive lion-tailed macaquesin 18 Indian zoos was recorded to identify the factors that influence the behavioural repertoire of captive lion-tailed macaques. 'Me first step was to construct a detailed ethogram; behavioural observations were then conductedu sing ad libitum sampling,f ocal animal samplinga nd instantaneouss cans. Sampling was carried out only during the day when visitors were present at the macaque enclosures. The results showed that stereotypic pacing was the most commonly exhibited behavioural. abnormality. Abnormal behaviours were only exhibited by confiscated and zoo-bom individuals but never by wild-caught and captive-reared animals. Active foraging behaviours were influenced by enclosure complexity. In order to determine what improvfments could be made to the zoo enclosures, two behavioural studies were conducted on six singly-housed captive lion-tailed macaquesi n ThiruvananthapurarnZ oo. In Study A, cotton ropes and a feeding basket were added to the enclosures and were later removed, while in Study B, the singly-housed individuals were transferred to a large open-moated enclosure in which they were group-housedI.n Study A, frequenciesa nd proportions of abnormal behaviour exhibited differed significantly across the five phases of the study with the lowest proportions being exhibited when the macaquesw ere fed in elevate d f eedi ng baskets. During this phase, frequencies of exploratory behaviours and other natural behaviours also increased. Self-biting exhibited by several of the singly-housed macaques appeared to be redirected towards the enrichment provided, thus reducing the overall levels of abnormal behaviour exhibited. In Study B, the six captive lion-tailed macaques exhibited significantly greater levels of abnormal behaviour when they were housed singly in barren cages. Individuals exhibited higher levels of active foraging when they were in group-housed in the open-moated enclosure. A further study was conductedt o investigatet he influence of visitors' presenceo n captive liontailed macaquesT. he behayioural study was conductedo n 35 individuals housed in 10 zoos across India. The study animals were observed on days with visitors present and on zoo holidays when there were no visitors. To record the long-term impact of visitors' presence on captive primate behaviour and welfare, another study following the same sampling method was conducted in which the behaviour of seven singlyhoused individuals was recorded independently in 'on-exhibit' and 'off-exhibit' enclosures of similar sizes. Captive macaques exhibited lower levels of abnormal behaviour on zoo holidays and the frequency of begging when off-exhibit was lower as compared to days with visitors present and in on-exhibit enclosures respectively. Even social behaviour was influenced by visitors' presence, with captive lion-tailed macaques exhibiting both higher proportion of time spent in social behaviour and higher frequencies of reproductive behaviour on zoo holidays. In conclusion, the presence of visitors, enclosure design, group composition and early rearing history were all found to influence the behaviour and welfare of captive lion-tailed macaques in the study zoos. Enriching the enclosures and changing the social circumstances of the macaques were found to positively influence the welfare of the study animals, because they led to them exhibiting more natural behaviours. Indicators that were most suitable in assessingt he welfare of captive lion-tailed macaquesi ncluded the physical-condition factor and the developmental and reproductive success factor accounting for the highest proportion of the total variance in the population. These factors were 'non-invasive' and 'hands-off and hence proved ideal for assessing the welfare of individuals that were part of a conservation breeding programme.

In cetacean monitoring for population estimation, behavioural studies or mitigation, traditional visual observations are being augmented by the use of Passive Acoustic Monitoring (PAM) techniques that use the creature’s vocalisations for localisation. The design of hydrophone configurations is evaluated for sperm whale (Physeter macrocephalus) range estimation to meet the requirements of the current mitigation regulations for a safety zone and behaviour research. This thesis uses the Time Difference of Arrival (TDOA) of cetacean vocalisations with a three-dimensional hyperbolic localisation algorithm. A MATLAB simulator has been developed to model array-configurations and to assess their performance in source range estimation for both homogeneous and non-homogeneous sound speed profiles (SSP). The non-homogeneous medium is modelled on a Bellhop ray trace model, using data collected from the Gulf of Mexico. The sperm whale clicks are chosen as an exemplar of a distinctive underwater sound. The simulator is tested with a separate synthetic source generator which produced a set of TDOAs from a known source location. The performance in source range estimation for Square, Trapezium, Triangular, Shifted-pair and Y-shape geometries is tested. The Y-shape geometry, with four elements and aperture-length of 120m, is the most accurate, giving an error of ±10m over slant ranges of 500m in a homogeneous medium, and 300m in a non-homogeneous medium. However, for towed array deployments, the Y-shape array is sensitive to angle-positioning-error when the geometry is seriously distorted. The Shifted-pair geometry overcomes these limits, performing an initial accuracy of ±30m when the vessel either moves in a straight line or turns to port or starboard. It constitutes a recommendable array-configuration for towed array deployments. The thesis demonstrates that the number of receivers, the array-geometry and the arrayaperture are important parameters to consider when designing and deploying a hydrophone array. It is shown that certain array-configurations can significantly improve the accuracy of source range estimation. Recommendations are made concerning preferred array-configurations for use with PAM systems.

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