Microbial organisms are adapted to live in every ecosystem on this planet, from hydrothermal vents to radioactive sludge. Yet, we still struggle to understand the evolutionary mechanisms that allow bacteria to adapt to novel environments. A primary mode of bacterial evolution is horizontal gene transfer (HGT), where microbes acquire genes from neighboring organisms. One mechanism of horizontal gene transfer, known as transformation involves the transformation and integration of extracellular DNA (exoDNA), which can be released into the environment from dead cells or actively secreted by living cells (i.e. biofilm formation). Model systems for bacterial evolution have extensively studied the mechanisms of transformation at the cellular level, however little is known about the rate of transformation in nature and the role this process plays in bacterial evolution. My research focuses on the ecological factors that promote the release and transformation of exoDNA, as well as more fundamental questions about the maintenance of transferred genes and their effect on host fitness.