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This study investigates the influence of feeding competition and predation risk on the behaviour and ecology of baboons. Four groups of chacma baboons (Papio cynocephalus ursinus) were habituated and studied over 12 months between 1990-91 in the Pro-Namib desert region of Namibia. Each group differed in size and composition (with 1-6 adult males occupying groups of between 22-55 members), but their ranges overlapped extensively. Additional data were collected describing (1) food quality and availability and (2) biologically relevant measures of predation risk. The results suggest that contest competition for food or safety was minimal both within and between groups in this population. However, scramble competition for food did occur, despite high levels of food availability. Female reproductive state had little influence on feeding or anti-predator behaviour. Females and individuals in small groups were shown to be at the greatest risk of predation, and responded as predicted by exhibiting the highest levels of anti-predator behaviour. Habitat use reflected a trade-off between food availability and the reduction of both diurnal and nocturnal predation risk. Individual spatial position within groups was influenced by male reproductive strategies and predation risk, although social constraints might also have been present. Vigilance in males reflected reproductive strategies while in females vigilance was aimed at predator detection. Trade-offs between foraging and predation risk were suggested in the patterns of home range habitat composition, the use of habitat in the home range, the presence of scramble feeding competition, the choice of feeding site and the choice of diet. In addition, large groups reduced feeding competition at the expense of increased predation risk. Finally, points of special interest included the reduction of predation risk by both (1) the active use of "rest" time and (2) the defensive behaviour of male group members.

Organisms are frequently faced with uncertainty regarding how best to exploit vital resources, and may benefit from collecting information about their distribution through space and time. However, the ways in which competition over resources might systematically facilitate or constrain an individual's ability to use information has been largely overlooked. In this thesis, I develop a conceptual framework for considering how the distribution of limited resources might underpin interdependencies between competition and information use. I focus on the evolutionary ecology of relationships between social dominance and social information use. I begin with an observational study of wild chacma baboons (Papio ursinus) suggesting that, when resources can be monopolised, individuals with low competitive ability are limited in their ability to use social information. Building on these findings, I then develop a general model exploring selection on social information use in a competitive context across three axes of 'resource ecology' (scarcity, depletion rate, monopolisability). This study makes predictions regarding the resource conditions under which competitive ability might constrain social information use, and the potential importance of social information use in the evolution of social dominance. I go on to test these predictions in chacma baboons using a field experiment. This experiment also explores whether the predictability of resource distribution might facilitate the decoupling of social information use from the competitive context in which it was collected. Taken together, these findings provide general insights into the combinations of ecological conditions and behavioural mechanisms that should underpin the benefits of social dominance. I end by building a simple population matrix model to study social dominance using an eco-evolutionary approach, in which feedback loops between ecological and evolutionary processes are considered. By modelling relationships between dominance rank and survival, reproduction, inheritance, and development, I am able to derive estimates of long-term fitness associated with dominance. Using these estimates, I generate predictions regarding how dominance hierarchies should impact the dynamics of group stability, viability, and fission.

There is convergence at the international level that conserving biodiversity can contribute to poverty alleviation, but empirical evidence for this relationship is scarce. In this thesis I assess the relationship between poverty and biodiversity, within the context of land use change, using a case-study from the Solomon Islands. This interdisciplinary study is based on both social and ecological data, primarily collected through focus groups, household surveys and avian line transect surveys. Poor households in Kahua were characterised by fewer members of a working age and fewer male members. They were also found to own fewer assets, which were correlated to lower land tenure. Natural resources, including wild foods, were a crucial resource for the consumption and income for poor households, with evidence of wild foods buffering shortfalls in household consumption. The livelihoods of poor households were dependent on natural resources, whereas wealthier households relied on cash crops. The lower involvement of poor households in cash cropping suggests that the poor have less access to such income sources, possibly through a lack of initial land holding assets. Cash crop areas of monoculture cocoa were the most intensive land use in Kahua and were found to be a poor habitat for many bird species, including most endemics. Overall, the relationship between poverty and biodiversity was found to be complex, context dependent and influenced by various social and institutional factors. Household inequalities in access to land and resources indicate that a social-ecological trap may be occurring for poorer households in Kahua, possibly perpetuated by the livelihoods of wealthier households. More research is required in translating the concept of social-ecological traps into management actions, but this thesis concludes that this could be a useful concept for improving poverty alleviation and biodiversity conservation initiatives.

This thesis investigates the dynamic relationship between the processes of extinction on islands and the traits of oceanic island endemic birds associated with persistence and vulnerability. This is explored using the comparative method and a data set of all birds endemic to oceanic islands. Two case studies are then presented to examine the resilience of the island endemic birds of Principe and Boné de Joquei in the Gulf of Guinea. When comparing closely related oceanic island and mainland birds, clutch size is lower on islands and, within islands it continues to decline as the distribution area of a species decreases. Small birds (< 27 cm in body length) tend to get larger, and there is a trend for sexual size dimorphism to increase on oceanic islands. Recent extinction rates are lower on islands that have been exposed to humans for a long period of time. The birds on such islands are also less threatened by the introduction of exotics. A long period of exposure to humans also reduces the probability that the remaining species are flightless, ground-nesting, or non-forest- restricted endemics. When comparing island and mainland species that have similar areas of distribution, there is no significant difference in extinction risk. However, island birds are more threatened by introduced species. On oceanic islands, flightless birds, ground-nesting birds, birds with larger body size, and habitat specialists are associated with a greater risk of extinction than other birds. Sexually selected traits such as sexual body size dimorphism and dichromatism are not associated with elevated extinction risk. The resilience of the island endemic birds on Principe appears to be associated with a unique land use history and evolutionary exposure to predators, competitors and disease. Finally, a state of super abundance may be essential for the long-term persistence of endemic birds on small remote oceanic islands.