The passing of Seymour Benzer has inspired various retrospectives on his scientific career, and much attention has been paid to his inauguration of single-gene mutant studies of behavior in the fruitfly Drosophila melanogaster. Studies of genes and behavior actually go back to the beginnings of genetics. The end of the era marked by Benzer's life offers a good opportunity to look back at the origins of the field he influenced so profoundly.