This article examines the role of aesthetics in scientific argument by analyzing two images. The first, from Ernst Haeckel's Art Forms in Nature (1904), depicts 15 bats evenly spaced on a white field. The second, Charley Harper's Darwin's Finches (1961), shows 13 finches, similarly displayed. Although these two images may at first appear to have little in common, they both present a specific interpretation of Darwin's theories using visual language. This article argues that the act of representation and scientific theory are inextricably intertwined.