albino [Port.,=white], animal or plant lacking normal pigmentation. The absence of pigment is observed in the body covering (skin, hair, and feathers) and in the iris of the eye. The blood vessels of the retina show through the iris, giving it a pink or reddish color, and the eyes are highly sensitive to light. Albinism is inherited as a Mendelian recessive character (see Mendel; genetics) in humans and other animals. Through experimental breeding, races of albinos have been established among some domestic animals, e.g., mice, rabbits, pigeons, and chickens. Albino animals are sometimes held sacred, for example, white elephants in Thailand and white cattle in India. The presence of an excess of black pigment is called melanism.