I actually wrote up a paper a few years back about this very topic. I also discussed the Pied "Marker" traits found on WT and Het. animals.



I hypothesized that the belly marker trait is due to another gene that influences the amount of white on a piebald. This also allowed for wild type animals to have the belly marker trait since it is a separate gene. At the time I wrote the paper the Yellow Belly was just beginning to excite breeders and the Ivory hadn't been produced. Since then we have seen the importance of various belly traits/genes on various known morphs.



As far as the amount of white being random. I disputed this, however, after sitting down and working out every possible combination of the piebald gene along with the various belly marker genes, the number of possibilities was staggering. Even a breeder with as many Piebalds as Peter Kahl would have had difficulty predicting the outcome of each of the clutches.



In essence, I do not think it is "random", however, the number of possibilities is so huge it seems random to the observer. Especially considering that ball pythons have such small clutches.

[ Show Entire Thread ]