Phenotypic and Genomic Evolution during a 20,000‐Generation Experiment with the Bacterium Escherichia coli

225 *Acknowledgments: Many individuals have contributed to this long-term experiment. Rather than trying to list everyone here, I will let the literature cited record many of the contributions of the graduate students, postdoctoral associates, and colleagues who have worked on this project. However, I want to emphasize the contributions of a few individuals in particular. Michael Rose played an important role in getting this project started, as his own long-term study selecting for delayed senescence in fruitflies provided an elegant model to emulate. The E. coli experiment has depended on the dedication of three outstanding technicians over the years: Sue Simpson, Lynette Ekunwe, and Neerja Hajela. And Madeleine Lenski has tolerated my long-term “affair” with this experiment. This research has been supported by the National Science Foundation (currently grant DEB9981397) and by Michigan State University. James Crow and Jules Janick provided many helpful comments on this paper. 4112 P-08 10/30/03 9:09 AM Page 225

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