Hey David. I doubt the field work will get you very far since you will not know the phenotypes of the parents. You will only be able to calculate frequencies of the different phenotypes. The captive breeding though might be fruitful in deciphering the genetics/heritability. I have only done breedings within the Davis locality and can back up Kerby's assertion that the hypermelanism is recessive. IMO this is only one of 3 or more genes that control pattern and color in this population. And yes I do consider it one population since black bellies are found nearly continuously from Davis south to Mendota. I like Hubb's term Delta kings for this reason. Back to the genetics. It seems much more likely that the black ventor, speckling, and aberrent pattern are controlled by separate genes on separate loci from the hypermelanism. This is because all these characters can be found independent of hypermelanism, eg. normal colored and even normal banded snakes with black venter with or without speckling. It would be a reach to believe that all these differing phenotypes were being controlled by mutations or variants of the same gene/loci.



Separate expression of these traits is much more common in the south. I have never seen a hypermelanistic snake from near Davis that was not also aberrent. Davis does have normal kings with only side speckling though, but to my knowledge none have been found with a black venter that were not also hypermelanistic. This suggests that the hypermelanism loci is very close to the loci controlling the aberrent pattern and the loci controlling the black venter. I have never heard of a hypermelanistic king that did not also have a black venter, so these two loci need to be very very close on the same chromosome. Sorry to get technical with the genetics but what this means is that the closer the loci are to each other the less likely it is that a crossover event will occur during meiosis that would separate the two loci and therefore the two phenotypes. This has obviously happened in the south since you can find normal colored snakes with black bellies or aberrent patterns. In Davis this is not the case as there are only normal banded snakes and hypermelanistic black bellied snakes. This is likely just due to the fact that these genes are much rarer near Davis so the chance of getting that cross over event to separate the phenotypes is much lower. I think Bobby said that about 1 in 3 to 4 kings down south had some or all of these aberrent genes. In Davis the numbers are more like 1 in 30 or more kings, and I am so due to find another one since I have at least 50 found since my last black belly. So David, I hope you are able to figure it all out. I am going to start cally you Mendel, if you succeed. If my postulate is correct you should even be able to calculate the genetic distance between the loci on the chromosome. The difficulty is that it may take many hundreds or more of breedings to get statistically meaningful numbers, especially if the genes are as closely linked as they seem to be.



Shoot me a pm or email if I am close.
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Rick Staub

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