This essay analyzes the late-nineteenth-century epidemic of hypertrichosis, the disease of "superfluous hair," in the context of the U.S. reception of evolutionary theory. Between 1877 and 1920 scores of dermatologists reported at conferences and in medical journals that their female patients were traumatized by excessive facial and body hair. At the same time, the public flocked to see bearded ladies on display at circus sideshows. To make sense of hirsute women, specialists and popular observers alike often invoked evolutionary theory, especially Charles Darwin's theory of sexual selection as explained in The Descent of Man, and Selection in Relation to Sex (1871). Studying the medical and popular fascination with female hirsutism sheds light on the understudied role that gender has played in the U.S. reception of evolutionary theory, reveals how the cultural norm of female hairlessness became naturalized, and helps us better understand the ongoing construction of gender, a highly racialized category.