Profile of Bruce Levin.

For population biologist Bruce Levin, opening the incubator to see how yesterday’s experiment worked is his ideal way to start the day. That anticipation has kept the Emory University professor of biology excited about his research on the population and evolutionary biology of bacteria for more than 40 years, and motivated a shift in interest from multicellular organisms to bacteria. Anything that takes longer than a day to see results, says Levin, takes too long. Levin uses mathematical and computer modeling and experiments with bacteria to investigate basic ecological and evolutionary questions. He employs the same techniques to study health-related problems, including the epidemiology and evolution of pathogenic bacteria and the population and evolutionary dynamics of antibiotic treatment and resistance. Elected to the National Academy of Sciences in 2012, Levin uses mathematical and computer simulation models to determine the optimal way to use antibiotics to treat acute infection, as described in his Inaugural Article (1). “Hopped Up” on Research Levin grew up in the Bronx, New York, and his parents hoped he would pursue a career in medicine. Not cut out for medicine, Levin decided to major in engineering when he was accepted at the University of Michigan, Ann Arbor. “Engineering was legitimate for my parents, though not as legitimate as real doctoring,” says Levin. However, engineering was not what he had expected. “My vision was that of a 19th century inventor. It was a very romantic idea and not at all like what I was learning in school.” After his second year, Levin switched to zoology. The subject matter was interesting, but he was no more motivated as a student. He soon discovered the joy of research during an introductory genetics class taught by Morris Foster. Levin wanted to avoid writing the required term paper and decided to leverage the computer programming skills he had gained as an engineering student. He asked Foster whether, instead of writing the paper, he might work on computer simulations of genetic phenomena. “Dr. Foster was what a teacher should be,” recalls Levin. “He was totally supportive of me, a hardly stellar undergrad. He introduced me to two graduate students working on mice, Mike Petras and David Rasmussen, and gave me a desk in a room I shared with some 1,000 deer mice. With Mike and David, I did my first research, a computer simulation of the population genetics of a lethal gene complex in house mice.” “Once I saw how much fun research was, I was totally hopped up and saw no choice but to go to graduate school,” he says. Levin stayed at Ann Arbor for graduate school. Thanks to his programming skills, he met William J. (Jack) Schull who agreed to be his PhD advisor, despite their differing interests. Levin wanted to become an ecological geneticist focusing on Drosophila, and Schull was a mathematical-statistical geneticist working on human populations. “Although I had my own lab and worked independently of him, Jack was always there when I needed advice. He still is, even now at 92,” says Levin. “He was extremely supportive of me and taught me to be the same with my students and postdocs.”