Independently synthesized and inherited pigments
In corn snakes, combinations of orange and black pigments determine the four phenotypes shown. (a) A wild-type black-and-orange camouflaged snake synthesizes both black and orange pigments. (b) A black snake does not synthesize orange pigment. (c) An orange snake does not synthesize black pigment. (d) An albino snake synthesizes neither black nor orange pigment.
[Anthony Griffiths.]