The cleverness of many MIT hacks has even resulted in urban legends about supposed hacks that may not have occurred. One rumored hack involved a certain student's adherence to classical conditioning behavior response, as studied by Harvard Professor B. F. Skinner. Throughout the off-season, this supposed student visited the Harvard football stadium during his lunch break. He dressed in a black and white striped shirt and trousers, filled his pockets with bird-seed, then went on the field, blew a whistle, and spread his birdseed on the field. The result of all of this effort, the story goes, is that on opening day as the Harvard football team took the field to face their opponent, the referee blew his whistle to signal the start of the game, and the field was suddenly inundated by a flock of birds looking for their lunch. Despite sounding like a classic MIT hack, this particular prank has never been verified. The author of a 1990 book about pranks pulled by MIT students stated that he had not come across clear documentation of this tale during his years of research.