The evidence: Here is the transcript from a Glenn Beck Tea Party, courtesy of the website Little Green Footballs (which has the video):
At a “Project 912 Glenn Beck Tea Party,” an unnamed speaker rants about “infiltration by the Communist Party” (a John Birch Society talking point), says that digital cable boxes are “brainwashing machines” planted in our homes by the government, and swears to stop paying taxes. The rant begins at about 1:58.
This is some really deranged stuff, and the audience is eating it up.
And notice the comment about evolution at about 5:00:
Woman: [Shouts] “Burn the books!” [applause]
Man: “I don’t think you were serious about that, were you?”
Woman: “I am too.”
Man: “Burn all the books?!”
Woman: “The ones in college, those, those brainwashing books.”
Man: “[laughs] Brainwashing books?”
Man: “Which ones are those?”
Woman: “Like, the evolution crap, and, yeah...”