If evolution is a scientific theory worth its salt, then there must be some conceivable observations that could show it to be wrong.
MORE: http://whyevolutionistrue.wordpress.com/2012/07/09/what-would-disprove-evolution/
Free iPad app: Evolution -- Making Sense of Life
http://richarddawkins.net/articles/646450-free-ipad-app-evolution-making-sense-of-life
