Leucism's a condition characterized by reduced pigmentation in animals. Unlike albinism, it's caused by a reduction in all types of skin pigment, not just melanin. Leucism's a general term for the phenotype resulting from defects in pigment cell differentiation and/or migration from the neural crest to skin, hair or feathers during development. This results in either the entire surface (if all pigment cells fail to develop) or patches of body surface (if only a subset are defective) having a la… (More on Leucism)