Understanding the evolutionary ecology of dispersal: An experimental approach using the bacterium Pseudomonas aeruginosa

Understanding dispersal is a central aim of evolutionary ecology. Theoretical analyses of dispersal have been crucial in identifying key variables which contribute to its evolution and maintenance, but the supporting empirical data remains elusive. Microbes offer a powerful model system on which ecological and evolutionary theory can be experimentally tested with controlled and replicated experiments, and with the convenient malleability of selective pressures and bacterial genomics. Pseudomonas aeruginosa is an ubiquitous, opportunistic pathogen that is able to induce acute or chronic infections in a broad array of hosts. As well as in vivo environments, P. aeruginosa can be found in a range of ecological habitats, from solid to aqueous, and as such requires a variety of dispersal mechanisms (including swimming, gliding on a surfactant and ‘crawling’) for effective colonisation and infectivity. In this thesis, I present a collection of papers which outline empirical ecological and evolutionary experiments to identify the abiotic and biotic forces that shape the evolution of these different dispersal mechanisms, with particular focus on the theoretically important role of kin competition and the structure of the abiotic environment.This thesis is not currently available in ORA