A gecko's tail continues to flip, flop and wriggle long after it has dropped off the lizard's body," Jennifer Viegas reports for the Discovery Channel. "Now a new study proposes the tail is preprogrammed for random movement to foil predators while the rest of the gecko makes a speedy getaway. . . . In the gecko's case, its tail is actually an extension of its spinal cord. No other animal, however, appears to be able to self-amputate a body part that can later move. It would be like a person dropping off one leg that continues to hop around while the rest of the person escapes