Don, the second son of Esker Arnold and Mildred Louise (Fortson) Davis, was born on March 28, 1934, in Oklahoma City, Oklahoma. The outdoor experiences from growing up on a small farm near the city greatly fostered his early interests in all phases of natural history, including everything from astronomy to zoology. During his high school years Don was an active participant in local and state science fairs. In his senior year he won honorable mention in the national Westinghouse Science Talent Search (with an article he wrote on the moth genus Schinia) and later won a trip to compete in the National Science Fair, which was held that year (1952) at the National Museum of Natural History in Washington, D.C. Because his exhibit (which won third place in the biology division) emphasized Lepidoptera, Don attracted the attention of staff members in the Museum’s Division of Entomology, especially of then head curator, J. F. Gates Clarke. Following Clarke’s initial urging to specialize in his particular field, Microlepidoptera, Don immediately embarked upon a career goal to work someday at the Smithsonian Institution.
Don received his BA degree in entomology at the University of Kansas in 1956. In 1962, he earned his PhD degree at Cornell University under John G. Franclemont, formerly a U.S. Department of Agriculture research entomologist at the Museum, whom Don had first met during the National Science Fair in 1952. Fulfilling a dream he had nurtured since high school, Don was hired by J. F. Gates Clarke and the Smithsonian Institution as a research entomologist in Microlepidoptera in the fall of 1961, and he continues in that position to the present. From 1976 to 1981 he served as chairman of the Department.
Don married Mignon Marie Bush in 1972, who had recently been hired as an assistant in the same department. They have been blessed with two wonderful children, Marisa Marie and Steven Ray. Marisa graduated from Ohio State University in 2003 with a degree in business administration. Steven graduated with a degree in entomology from the University of Maryland in 2005 and is now pursuing his doctorate in this field.
Since his graduate days, Don’s research has focused on the more basal groups of Lepidoptera. He has published important references on many of these, in particular the families Acrolophidae, Carposinidae, Eriocottidae, Eriocraniidae, Opostegidae, Prodoxidae, Psychidae, and Tineidae, as well as on the new families Acanthopteroctetidae, Andesianidae, and Palaephatidae. Much of his research emphasizes the biology of his subjects and their immature stages. In recent years he has concentrated on the biology of plant-mining and cave-dwelling moths and is now completing major works on the Adelidae, Epipyropidae, Gracillariidae, Nepticulidae, and Tineidae. Currently he is involved with a Lepidoptera ATOL (Assembling the Tree of Life) project which will propose a family phylogeny for the order based on genomic and morphological data. Don’s various activities have involved him in field work in over 45 countries that have resulted in the addition of nearly one million specimens to the National Museum. In 1977, he was awarded the Jordan Medal by the Lepidopterists’ Society for his work on yucca moths and their allies (Prodoxidae).
Don has served as president of the Entomological Society of Washington (1977), the Lepidopterists’ Society (1985), and the Biological Society of Washington (1985-86). He was elected to membership in the Washington Biologists’ Field Club in 1972. Don has served on the research committee for several years, including serving as chairman from 1977 to 1981 and is currently a member of this committee.