Re: albinism & melanism (aka ebony & ivory?)

[Betty Cunningham <bettyc@flyinggoat.com>]

The birds I've seen with albinism, partial albinism, and melanism only
show the coloration change on the feathers-beaks and feet don't seem to
change color.  Is this really true?  Would an albino toucan have a
dirty-yellow-unstriped beak or a normal one?  

Albinism in mammals is bad for the animal in that our pigment provides
us with quite a lot of protection from UV radiation, as well as
protecting our vision from glare (human albinos are frequently legally
blind).  I don't know if a pink dino would be any more or less sensitive
to sunburn than a green dino, but a pink dino certainly wouldn't SEE as
well.  

One of the massive dinosaurs (1 ton plus) has enough surface area as an
adult to absorb rather a LOT of UV radiation. I would expect an albino
sauropod would be normal as a juvenile but as it grew it would develop
MAJOR skin problems such as sores, funguses, etc.  Wounds might not heal
as well as on a non-albino.

The odds are that albinism happens with dinsoaurs but the animals would
have as little chance of survival as albino mammals do now, with the
larger dinosaurs being VERY RARE as albino adults (and they'd be gross)


-Betty Cunningham

Andrea Kirk wrote:
> 
> For some reason the strangest idea popped into my head this morning...
> Albinism is known in archosaurs (well-known in birds, and I have seen an
> albino alligator in my lifetime), so it's a pretty reasonable guess that
> some dinosaurs were albinos, isn't it?  Yet I've never seen any
> portrayed that way in reconstructions.  Imagine something like an
> *Oviraptor* (I'm thinking of Luis Rey's neato version) colored in all
> white and pink. Or even better (worse?) an albino therizinosaur. Just
> when things couldn't get weirder...
> 
> On the same thought, is melanism documented in reptiles and birds? It's
> pretty common in mammals (like all the black squirrels around PLS, right
> Dr. Holtz? :-) but I don't recall ever seeing something like a black
> alligator.
> 
> Andrea Kirk
> University of Maryland
> http://animedomain.com/xianghua

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