Most of what I know about calico ball pythons comes from the link below. The matings and their results come from applying genetics theory to that information.



Homozygous calico = a calico ball python with a pair of calico mutant genes.



Heterozygous calico = a calico ball python with a calico mutant gene paired with a normal gene. Heterozygous calico ball pythons do not look normal. Most if not all calico ball pythons alive today are heterozygous calico.



If it is possible to reliably tell the homozygous calicos from the heterozygous calicos, then the five possible matings would produce the following:



1. Homozygous calico x homozygous calico -->

all babies homozygous calico



2. Homozygous calico x heterozygous calico -->

1/2 homozygous calico

1/2 heterozygous calico



3. Homozygous calico x normal -->

all babies heterozygous calico



4. heterozygous calico x heterozygous calico -->

1/4 homozygous calico

1/2 heterozygous calico

1/4 normal (in both appearance and genes)



5. heterozygous calico x normal -->

1/2 heterozygous calico

1/2 normal (in both appearance and genes)



If you can't tell homozygous calico ball pythons from the heterozygous calicos without a breeding test, then the results from matings 1, 3, and 5 are unchanged. Matings 2 and 4 would be changed as follows:



2. Homozygous calico x heterozygous calico -->

all babies calico (50% probability homozygous calico, 50% probability heterozygous calico)



4. heterozygous calico x heterozygous calico -->

3/4 calico (66% probability het calico, 33% probability homozygous calico)

1/4 normal (in both appearance and genes)



If homozygous calico ball pythons die sometime after fertilization of the egg and before sexual maturity, then matings 1, 2, and 3 would be impossible. Matings 4 and 5 would remain as given above.



Paul Hollander
calico ball pythons

[ Show Entire Thread ]