Evolutionary dynamics of microbial communities

Abstract

Deciphering the structure and dynamics of communities containing a multitude of species is a topic of great interest to many microbial ecologists. Species interactions have been observed to alter the evolutionary trajectories of communities when subjected to different evolutionary processes. Thus far, many of the studies focused on gaining insight into these processes, do so through the manipulation of pre-existing functions and mechanisms. Though few develop the field of multi-species experimentation in bacterial community knowledge via the implementation of more general and broad theoretical applications. In this thesis I develop a better understanding regarding the evolutionary dynamics of bacterial communities by combining both ecological and evolutionary techniques. By employing the use of a bottom-up approach, through the construction of relatively simple artificial bacterial communities from a library of isolated naturally co-occurring bacteria, I provide insightful evidence of multiple dynamic interactions between different guilds of species. The research presented in Chapters 2, 3 and 5, highlight the impacts that choices in experimental design have when working with multi-species in an experimental setting and increase knowledge of how biotic and abiotic interactions influence community dynamics. Finally, Chapter 4 produced novel insights into previously unexplored areas of community complexity and dynamics; describing the important interplay between intraspecific and interspecific dynamics on community progression.