Originally Posted By: Redcap
The oldest papers about this topic are:

Kimball, E. (1951). Pyle-Black Plumage in the Fowl. The American Naturalist 1951 85:823, 265-266
I have to scan it, when I am back to University in January.


I found a digital version and uploaded it.
http://documents.kippenjungle.nl/#post37
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