Well Frank Retes says he has lived in alot of different areas and bred alot of alterna and that climate and location does influence pattern. I think it's quite possible there's an influence from environmant but genetics obviously play some role too, IMHO, as I have seen alot of babies that carry marking similar to parents even down to having the same odd looking band. I had a king that would always produce a couple with the same odd V-shaped band and an alterna that would sometimes produce the same crooked alternate.
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