“Bulls are enraged by the color red.”

The enduring image of a matador waving a vibrant red cape to infuriate a bull is a classic scene, deeply woven into popular culture, cartoons, and common sayings. This misconception likely stems from the dramatic spectacle of bullfighting, a tradition with roots dating back centuries in Spain. Observers naturally associate the bull's aggressive charge with the striking red color of the cape, known as a muleta, believing it to be the source of the animal's rage.

However, scientific evidence reveals that bulls, like most cattle, are dichromats, meaning they are colorblind to red. Their eyes possess only two types of color-detecting cone cells, limiting their vision to a range of blues and yellows; red appears as a shade of yellowish-gray to them. Experiments, including those conducted by the television show MythBusters, have consistently shown that bulls react to movement, not color. Whether a cape is red, white, or blue, a bull will charge the one that is moved aggressively, while ignoring stationary objects or people, regardless of their color.

The tradition of using a red cape in bullfights serves a practical purpose for the human audience, not the bull. The vivid red color helps to mask the blood from the bull's injuries, making the gruesome aspects of the fight less apparent to spectators and maintaining the dramatic aesthetic of the event. Therefore, the widespread belief that red enrages bulls is a classic myth perpetuated by the visual drama of bullfighting and a misunderstanding of bovine vision, rather than any actual aversion on the part of the animal.