Xanthochromism (AKA xanthochroism, xanthism, or lutinoism) is what happens to an animal when, by reason of genetics or nutrition, either it has an excess of yellow pigmentation or is severely lacking in darker pigmentation that results in yellow and red coloration becoming visually dominant. This is found most commonly in reptiles and birds, although it has been known to happen to fish. When a bird, lizard, or fish present these characteristics, they are called "lutino," or "a lutino."