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Similarities in brain size, life histories, psychology and behaviour in parrots, corvids and apes suggest that certain socio-ecological selection pressures may have driven the convergent evolution of cognition in these families. However, very little is known about parrot behaviour and cognition, outside of African greys and kea. Therefore, captive red-shouldered macaws (Diopsittaca nobilis) and black-headed caiques (Pionites melanocephala) were presented with a variety of tasks to assess their social and physical cognition and behavioural flexibility. Although these species possess many similarities in their life history and ecology, there are also substantial differences in their morphology and natural habitats that could have driven differences in their cognitive evolution. Observations of social and physical interactions in both species revealed that macaws engaged in high levels of affiliative behaviour, and object neophobia, whereas caiques displayed high levels of social play and object exploration. However, such differences did not appear to result in differences in their social or physical cognition. Macaws and caiques displayed comparable performances on Serial Reversal Learning tasks (as an index of behavioural flexibility). Both species also demonstrated similar performances on two Means-End transfer tasks and a series of innovative foraging tasks that were designed to assess their comprehension of object relationships. However, macaws and caiques appeared to solve such problems by generalising learned information across novel tasks. Overall, these findings suggest that these two species may approach certain socio-ecological problems using flexible cognition that may be generalised across different problems, supporting claims for a domain general intelligence.

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Pursuit behaviours are vital in predator-prey interactions and in courtship for many flying animals. Existing research on target-directed flight behaviours in insects, birds and bats has aimed at identifying simple geometric rules describing the pursuit-flight trajectories. However, these geometric rules are only part of the picture as they only consider the outcome of the commanded changes in flight kinematics, and not the underlying guidance laws (dynamics) which generate these commands. To intercept a target, a pursuer implements a guidance law using sensory feedback to determine the required change in flight velocity, and the resulting kinematics determines the flight geometry. Most of the research until recently has examined insect flight systems, as the ethics of working with birds of prey are more complex and measuring their wide-ranging flight trajectories is difficult. Studies of predator-prey pursuit in birds have only described the geometrical rules for target interception, therefore overlooking the guidance laws which implement them. Therefore the aim of this thesis is to complete the picture by identifying the guidance laws used by birds of prey as they pursue and intercept targets both in the air and on the ground. I used onboard cameras and GPS to study attack flights in peregrine falcons (Falco peregrinus), and high-speed ground photogrammetry for attacks in Harris' hawks (Parabuteo unicinctus), to show that two different raptor species effectively implement the same guidance law of pure proportional navigation for intercepting manouevring and non-manouevring prey-targets. Proportional navigation is a feedback law whereby the bird's line-of-sight rate is fed back, in order to command a turn-rate in proportion to the change in line-of-sight rate, with a constant of proportionality N. Harris' hawks were found to use this guidance law in its simplest case with an N of approximately 1. This amounts to a pure pursuit course, meaning the bird maintains a heading angle of zero at all times (its velocity vector points at the target). Peregrine falcons were found to use a variety of values of N resulting in a quicker path to interception. A remarkable feature of most bird of prey eyes is that they possess two regions of high visual acuity - the shallow and deep foveae. The deep fovea is optimised for long-range vision, and is directed at approximately 45° to the side of the head. It has been proposed that the head is held in line with the body for streamlining, while the body is turned in flight to fixate the image of the prey on the deep fovea, resulting in a curved trajectory. My results contradict this theory, as falcons were seen to use saccadic head movements to maintain the image of the prey in their field of view whilst flying along curved trajectories - suggesting a different visual strategy. I provide the first quantitative analysis of how birds are able to guide their flight for successful prey capture. Not only does this provide new insights into animal behaviour and evolution, but this research has many applications in engineering, where there is a wide and growing interest in vision-based approaches to guidance and control in both civil and military spheres.

Social interactions can have profound influences on an individual’s fitness. As part of a long-term research program on the mechanisms and functions of social behaviour in fruit flies (Drosophila melanogaster), we addressed two main questions. First, we asked whether social behaviour is positively correlated between the larval and adult stages. We quantified genetic variation in social behaviour by measuring aggregation among larvae and adults taken from each of 29 inbred, wild-derived lines. We found significant genetic variation in social behaviour in both larvae and adults. While these lines also showed significant genetic variation in baseline locomotor activity, it had no significant influence on social behaviour. We found that neither social behaviour nor activity were correlated between larval and adult flies. This is consistent with the hypothesis that metamorphosis adaptively decouples the expression of genes between distinct life stages in animals with complex life cycles. That is, genetic variation in social behaviour during each life stage may reflect adaptation to the specific ecological settings during that stage. Our second question was whether social behaviour in adult flies was influenced by indirect genetic effects (IGEs), defined as the effect an individual’s genotype has on the phenotype of an interacting partner. IGEs can have profound effects on the rate of phenotypic evolution. We found that groups of 6 focal males maintained shorter inter-individual distances among themselves when interacting with 12 males from a line previously identified as highly social than when paired with 12 males from the least social genotype. Overall, our results indicate that heritable genetic variation influences an individual’s predisposition to engage in social behaviour as well as its effect on social interactions among other individuals it encounters. / Thesis / Master of Science (MSc)

The kea is the only parrot species in the world to include the true alpine environment as part of their habitat. Survival in these harsh alpine conditions has been hypothesised to be the cause of the generalist behaviour of kea, leading to their heightened explorative behaviour and curiosity. Kea are also widely regarded as being extraordinarily intelligent. It is their intelligence that suggests that kea may possess a sophisticated communication system. I conducted a study exploring the potentially complex vocal repertoire of the kea. My study was conducted with wild population of banded juvenile and fledgling kea in Aoraki/Mount Cook National Park between February 2003 and April 2004. I obtained 449 vocalisations from 16 identified and several unidentified kea. The results of this study confirmed that the vocal repertoire of the kea is exceptionally large for a parrot species, encompassing over 17 vocalisations. This study revealed five vocalisations previously undescribed in the kea repertoire and showed for the first time that vocal repertoire of immature kea may be different to the repertoire of adult kea. Two possible gender specific vocalisations were also revealed. The study of apparent vocal responses revealed that kea appear to be able to identify vocalisation types and respond accordingly using combinations of increasingly complex vocalisations. This is also the first study to take advantage of the similarity between human and parrot vocal systems for the kea, by utilizing powerful human speech analysis software. The results of this analysis allowed the identification of subtle differences in kea vocalisations, including the presence of graded signals, not identifiable by use of spectrogram analysis.

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Very little is known about cattle vocalizations. The few studies available in the literature have been conducted using animals under stress or very intensive husbandry conditions. Similarly, the individual consistency of behaviour in cattle has rarely been considered except in applied studies of constrained and isolated animals, and no previous research has attempted to address a possible association between vocal communication and temperament in cattle. The studies reported here address these gaps in our knowledge. I found that cattle contact calls have acoustic characteristics that give them individualized distinctiveness, in both adult cows and calves. These results were confirmed using playback experiments, where I found that there is bidirectional mother-offspring recognition, as has been recorded in other “weak hider” ungulates. Additionally, using visual and acoustic stimuli, I assessed individual cattle temperament. The results showed that there was no individual behavioural consistency in responses to a novel object presentations. However, calves behaved consistently more boldly than cows. Furthermore, there was significant individual consistency in responses to vocalisations of heterospecifics, when they were played back through a speaker in the field. Surprisingly, no correlations were found between the ability of cattle to identify their own mother/offspring and the acoustic features of their vocalisations, or behavioural responses in any other context. There were, however, significant correlations between one characteristic of vocalisations in adult cows (formant spacing) and the boldness of behavioural responses to both novel objects and auditory stimuli. Additionally, higher F0 in calf contact vocalizations correlated with boldness in the auditory stimuli experiment. These relationships imply that vocalisations may encode information about individual temperament, something which has rarely been documented. Surprisingly, no strong correlations were found between the behavioural responses to visual and acoustic stimuli, suggesting that individual consistency in behaviour across contexts was limited, and that behavioural plasticity could play an important role in determining responses in different environmental contexts. Overall, my results contribute to our knowledge of animal communication in mammals from a bioacoustic point of view, and they are also potentially relevant to studies of vocalizations as indicators of cattle welfare.