This thesis presents a series of studies investigating laterality in chimpanzees and its links with personality examined as behavioural style and social networks. The studies presented in this work were conducted by observing a group of 19 chimpanzees in captivity and present new findings in this species. However, this thesis has a broad evolutionary perspective, addressing important questions regarding personality and laterality that could prove helpful to the understanding of the evolution of laterality in vertebrates. Chapter 1 offers a general review of the three main areas of knowledge investigated: laterality, animal personality and primate social networks. Then, the first study of this project, presented in Chapter 2, began by exploring hand preference in the chimpanzee group, investigating spontaneous actions and unimanual tasks and expanding previous research by studying posture, between-task consistency and temporal stability. Chapter 3 investigated additional measures of motor laterality and proposed a novel way of measuring laterality in primates. Together, Chapters 2 and 3 directly examine laterality in chimpanzees and serve as the base from which to explore the links between laterality, personality and social networks in the subsequent studies. If lateralization is rooted in emotional processing and hemispheric lateralization, then individual differences in behaviour (particularly those that reflect emotional expression) would show a relationship with individual laterality. In order to address this question, Chapter 4 studies behavioural style in chimpanzees and its possible link with laterality. Simultaneously, if intraspecific coordination plays a role in the development of population level laterality, similarly lateralised individuals would likely have strong bonds to coordinate with each other. Chapter 5 introduces the approach and techniques of social network analysis and uses them to explore and describe the social structure of the group while describing the integration of a new adult chimpanzee. Chapter 6 applies social network analysis to explore if laterality plays a role in the way the group is structured. Lastly, Chapter 7 integrates all empirical chapters and presents the final discussion and conclusions of the thesis
