Posted by David Graham on December 16, 2010 at 4:03 PM
Great capture! This one is a piebald individual...it is technically a pronounced example of local leukism ( or local/multifocal amelanosis.)
Just to review:
total / pan-corporeal amelanosis (complete absence of melanin pigments) = albinism.
Normal color with patches of white , or white with patchy "remains" of normal color = piebald ( forms of leukism)
Note that the most pronounced form of leukism that is often mistaken for albinism is that in which only the
Claws and irises of the eyes are normally pigmented; easily overlooked in an animal otherwise lacking in melanin deposition.
There are also mutations resulting in decreased deposition of melanin...so-called "dilute" phenotypes. Such mutants, like pronounced leukistic ones, generally do not survive in their normal niches to effectively establish the mutation in subsequent generations. The dilution mutation is not , however, particularly rare in most species and can persist in local populations in niches where the dilute coloration/pigmentation confers a survival advantage...witness the normally pigmented and the palid ground squirrels existing within , in some cases, a few hundred yards of each other at the edge of fertile, well-grassed prairie and adjacent erosion "badlands" (and numerous other examples of that ilk).
Discussion
3 replies- Luke
Sandy
Just to review:
total / pan-corporeal amelanosis (complete absence of melanin pigments) = albinism.
Normal color with patches of white , or white with patchy "remains" of normal color = piebald ( forms of leukism)
Note that the most pronounced form of leukism that is often mistaken for albinism is that in which only the
Claws and irises of the eyes are normally pigmented; easily overlooked in an animal otherwise lacking in melanin deposition.
There are also mutations resulting in decreased deposition of melanin...so-called "dilute" phenotypes. Such mutants, like pronounced leukistic ones, generally do not survive in their normal niches to effectively establish the mutation in subsequent generations. The dilution mutation is not , however, particularly rare in most species and can persist in local populations in niches where the dilute coloration/pigmentation confers a survival advantage...witness the normally pigmented and the palid ground squirrels existing within , in some cases, a few hundred yards of each other at the edge of fertile, well-grassed prairie and adjacent erosion "badlands" (and numerous other examples of that ilk).
Dave Graham, East River, SD
Dave Graham, East River, SD