side-by-side comparisons of an albino house sparrow and a melanistic house sparrow. albinism results from a lack of the pigment melanin, and melanism results from an overproduction of that pigment.

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house sparrow color mutations

1. house sparrow with regular coloration

2. pied house sparrow (partial leucism)

3. “blonde” house sparrow (leucistic)

4. albino house sparrow

5. melanistic house sparrow

this house sparrow is unusually dark because it is melanistic. animals that have a genetic mutation called melanism overproduce dark pigments, leading to unusual appearances like that of this bird.

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this is ashley the barn owl. ashley is melanistic, which means his body produces too much black pigment – the opposite of albinism.

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this melanistic black-capped chickadee was seen at a feeder in maine. melanism is the opposite of albinism – too much pigmentation is produced rather than too little.

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