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Re: Help Please



At 11:38 AM 28/01/01 -0500, Ray Stanford wrote:
Isn't keratin the albuminoid that forms the chemical basis both
feathers, nails, hair, and even horn?  Dinosaurs had nails (thus keratin),
and I don't see why keratin for feathers should have been a problem, if
that's what someone is implying.

This is where we need Alan Brush! In the meantime, my understanding is that reptiles (including birds) produce two types of keratin, alpha (which we produce too) and beta (restricted to reptiles), and that feathers are made of beta keratin. As the same is true for reptile scales and the scutes of turtle shells, I hardly see how this could be used one way or the other to determine the relationship of birds within Archosauria, but then I've been wrong before....



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Ronald I. Orenstein Phone: (905) 820-7886
International Wildlife Coalition Fax/Modem: (905) 569-0116
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