Seen on the internet (commenter CapnFatback at Wonkette):

Walker replied, “Based on what I see in the mirror each morning, I’d say that no, the theory of evolution is not true,” before hurling his feces at the crowd, slashing teacher union funds, and dragging his knuckles as he galumphed off the stage.

wonkette.com

This would have been an honest answer by Scott Walker to the evolution question.