Thanks Cole,

Boy, it's been awhile since I've glanced at Dr. Bechtel's book or anything substantial on the synthesis of herp chromatophores, so like I feared, I was liable to make a hash out of my statement earlier. LOL

But I'm in the library now and have Bern's book in my hands.

One point that I tried to make was that, on a cellular level, Bechtel does not make any distinction between erythrophores and xanthophores (pigment-containing cells). He states that erythrophores are xanthophores with predominantly red pteridines, and that we call them erythrophores based on appearance or phenotype only. In other words, they're still xanthophores. (You've already said some of this stuff...I'm just thinking "out loud" here.)

The reds and yellows (and intermediates) are a combination of pteridines (pigments synthesized by the xanthophores) and carotenoids (not synthesized by the xanthophores, but are dietary in origin).

My point is that, on a cellular level, Bechtel does not recognize anerythrism. He even calls what we usually refer to as anerythristic Hondos and anerythristic Corns as axanthics.

Using the Corns as an example, an Anery type A is one that is born black and grey with no yellow or red, but as they mature and ontogenetically change with the xanthophores incapable of producing pteridine reds and yellows, they still accumulate dietary carotenoids of yellow color in the neck, chin, and other close-by areas.

Anery type B (charcoal) is a bit confusing using this example, because, when they are born, they are also a variant of black and grey, but they appear to accumulate much less dietary yellow than type A aneries. Or, could they be a manifestation of a higher degree of axanthicism (similar to the way a T-negative albino demonstrates a greater degree of amelanism than T-positive albinos -- this is an oversimplification here) than type A aneries?

Maybe Caramel Corns should be classified as a "hypoxanthic", reducing or eliminating red pteridine-containing xanthophores while leaving the yellow pteridine-containing xanthophores, which enhance in yellow even more as they mature and accumulate carotenoids.

Of course, "hyperxanthic" would appeal to most hobbyists here, since we tend to mostly think in terms of phenotype. And maybe an overproduction of yellow pteridines is what is happening anyway. Then, where does that leave Bloodreds?

Whew!! I agree that we should have an expert post in here (like Dr. Bechtel), instead of someone who is trying to interpret his work.

DR

p.s. More later! This is very interesting stuff.

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