Bulls charge at the color red
Bulls are colour-blind. They react to movement. They react to movement. A fighting bull instinctively recognizes a jurisdiction within which it will attack everything that moves. This jurisdiction will contract and expand during the bull's performance in the ring; at times it can reach right across the width of the bullring, or be as close as a few centimetres away from his horns. A bullfighter or torero will have to learn to judge the distance from which the bull will attack at any given moment during his performance. Good bullfighters will also learn how to control by contracting and expanding the distance from which the bull will be attacking.