Bacteria undergo many thousands of generations during a human lifetime, and thus they can evolve rapidly with potentially important consequences. In this long-term experimental research, the dynamics of bacterial evolution are being monitored, measured, and preserved for thousands of generations in twelve populations of Escherichia coli in order to examine the dynamics of evolutionary change, the predictability of outcomes, and the coupling of phenotypic and genetic changes. Specific objectives include daily propagation of the experimental populations, periodic storage of samples, and competitions between the evolved and ancestral strains. A key feature of this system is that the ancestral bacteria can be frozen and revived for later study.
Owing to the important roles of bacteria in nature, it is imperative that society understands the principles that govern their evolution. This project will provide fundamental knowledge about these principles that may inform policies on managing infectious diseases and environmental practices. For example, the principal investigator has consulted with federal agencies about the relevance of this research for predicting the rate of genetic change in pathogens, including those used in bioterrorism. This project also addresses a subject of great interest to many members of the public, specifically how organisms adapt to their environments.