The bacteriologist Alice Evans was a pioneer both as a scientist and as a woman. Evans discovered that the Brucella bacteria, contracted from farm animals and their milk, was the cause of undulant fever in humans, and responded by fighting persistently for the routine, improved pasteurization of milk, eventually achieving success. She was the first woman president of the Society of American Bacteriologists (now American Society of Microbiology). Although marginalized early in her career, Evans overcame many obstacles and lived to see her discoveries repeatedly confirmed. She had a major impact on microbiology in the United States and the world, and received belated honors for her numerous achievements in the field.

Alice Catherine Evans was born on January 29, 1881, in the predominantly Welsh town of Neath, Pennsylvania, the second of William Howell and Anne Evans' two children. William Howell, the son of a Welshman, was a surveyor, teacher, farmer...