The [[ACLU]] challenged a Tennessee statute, the Butler Act, that imposed a fine for teaching in government schools that man descended from more primitive life forms. The statute did not prohibit teaching most aspects of [[evolution]]. The textbook at issue in the case, ''[[A Civic Biology]]'', taught evolution, stating that man was descended from lower life forms.
===Textbook issues===
The ambiguous nature of scientific diagrams of evolution led to much public confusion and fueled the fireworks at the trial. Prosecutor Bryan argued against a textbook diagram that placed humans in a seemingly insignificant position, included with other mammals in a small circle, while lower forms such as insects appeared more prominently. Other visual representations, especially family trees and linear comparisons of primate skeletons failed to depict the influence of time, making humans appear more closely related to apes than scientists intended to suggest. Such diagrams were extensively used in books and cartoons aimed at popular audiences, making the controversial assumption that "man is descended from monkeys" the most common view of evolution, even though scientists had yet to reach a consensus on the matter. Despite efforts by paleontologists such as the president of the American Museum of Natural History, Henry Fairfield Osborn, to defend evolution while upholding religious belief, the popular - though misleading - images proved more persuasive.<ref> Clark (2000)</ref>
==Bryan vs Darrow==