Erik R. Zinser received his AB from Kenyon College, where he worked in the lab of coauthor Joan Slonczewski. He received his PhD in microbiology from Harvard Medical School for his research with Roberto Kolter on the evolution in Escherichia coli during prolonged starvation. He performed his postdoctoral research at MIT with Penny Chisholm on the ecology of the marine cyanobacterium, Prochlorococcus. He currently teaches in the Department of Microbiology at the University of Tennessee-Knoxville. He and his students study phytoplankton and associated bacteria from marine and freshwater environments. Laboratory and field studies by his group led to the development of the Black Queen Hypothesis, an evolutionary theory that explains the adaptive nature of genome streamlining in free-living microbes. He has been a member of the American Society for Microbiology since college and has served on the editorial boards for the journals Applied and Environmental Microbiology and Environmental Microbiology.