A redneck’s trying to become a naturalist. First, he decides to study the flea. He takes a flea and puts it on a white piece of paper and yells: “JUMP!”
The flea jumps, so the redneck cuts his legs off.
“JUMP!”, he yells. But this time the flea doesn’t jump.
Pleased with himself, the redneck writes in his entry book: “After having his legs cut off, the flea became deaf.”