"Lisa the Skeptic" is the ninth episode of "The Simpsons"' ninth season. It first aired on the Fox network in the United States on November 23, 1997. On an archaeological dig with her class, Lisa discovers a skeleton that resembles an angel. All of the townspeople believe that the skeleton actually came from an angel, but skeptical Lisa attempts to persuade them that there must be a rational scientific explanation. The episode's writer, David X. Cohen, developed the idea after visiting the American Museum of Natural History, and decided to loosely parallel themes from the Scopes Monkey Trial. The episode also makes allusions to actual hoaxes, such as the Cardiff Giant.