Subject: Re: albino Paridae
Date: Oct 25 10:15:54 1994
From: "David B. Wright" - wrightdb at pigsty.dental.washington.edu



On Tue, 25 Oct 1994, Dennis Paulson wrote:

> Brian Schmidt of the Burke Museum, to whom I forwarded some albino
> chickadee material, had this to say:
>
> "I have one question. How can feathers turn colors after they have
> already grown? I am sure you have noticed that museum specimens of 100+
> years do not turn white and they have been without proper nutrition.
> (It's hard to forage when you're stuck in a museum tray!) Aren't grown
> feathers composed of "dead" tissue? How could nutrition/poor health
> possibly influence the state of inactive tissue? Either I don't have my

Isn't it likely (at least possible) that the feathers in question were
always white; i.e., that they were formed that way? [failure to deposit
pigment (probably melanin) in developing feather]

David Wright
dwright at u.washington.edu

> facts straight, or these color changes are the result of some
> environmental factor (wear and tear, UV radiation, cage cleaner,
> something on the seeds, etc...)."
>
> Good point.....and also relevant for David Wilbur's comments of new
> feathers apparently replacing the white ones on his partial albino.
> Remember, feathers normally change color only because an old feather is
> replaced by a new feather during molt--they don't change color themselves.
> And these birds don't normally molt during midwinter. So I would *not*
> expect the albinistic birds to gradually become "normal" during the winter
> or spring.
>
>
> Dennis Paulson phone: (206) 756-3798
> Slater Museum of Natural History fax: (206) 756-3352
> University of Puget Sound email: dpaulson at ups.edu
> Tacoma, WA 98416
>
>
>