Evans was born in Neath, Pennsylvania, on January 29, 1881. After completing her primary education and studying for one year at the Susquehanna Institute in Tonawanda, she began teaching in a local elementary school. Four years later, she decided to pursue a college education and entered Cornell University for a two-year nature study course. She became so interested in science that she decided to remain at Cornell for a bachelor of science degree in agriculture.

With the support of her bacteriology professor at Cornell, Evans received a scholarship to the University of Wisconsin and, in 1910, received a master's degree from that institution. She often thought about studying for a doctoral degree, but became so involved in her own research that she never attained that goal.

After graduation from Wisconsin, Evans accepted a research job with the Department of Agriculture, working first in Wisconsin and later in the Dairy Division Laboratories...