It's common belief that bulls are infuriated by the red color of the muleta in bullfights. But is that really the reason? Do bulls hate the color red?

The answer is no. Surprisingly, bulls are colorblind to red. The true reason bulls get irritated in a bullfight is because of the movements of the muleta.

Bulls, including other cattle, are dichromat, which means they can only perceive two color pigments. Humans, on the contrary, can perceive three color pigments: red, green, and blue. Bulls cannot detect the red pigment, so there is no difference between red or other colors. 

Therefore, it doesn't matter which color is the cape, the bulls will be irritated by the moving gestures made with it by the matador.

Then why do they choose the red muleta? One very important reason is that the red masks the bull's blood during the bullfight.

(Cover image via VCG)

(If you want to contribute and have specific expertise, please contact us at nature@cgtn.com.)