Reptile & Amphibian Forums

I am young and just getting into the hobby (but starting to learn very quickly). I started with burms last year, and am now moving to ball pythons. I have some questions that im sure would be easy for you seasoned pro's to answer. I am looking to get into the pastels and spiders, of course to make bumble bees, and was curious how the "super pastels" I see around are made? Is it possible for me to come out with any super pastels from a spider and regular pastel cross? I have also heard about killer bees, and am guessing that is a super pastel-spider cross.....? Or is it possible for me to come out with killer bees from regular pastel-spider cross too? If someone can break down the ratios it would be great. I did read in a past message that from a super pastel you get all pastels, and no hets (something along that line....?). So that would mean that from a super pastel-spider cross I would get 1/4 bumble bee, 1/4 super pastel, 1/4 spider, and 1/4 killer bee........???? Thank you very much for your time and I am looking forward to the responses!

>I am looking to get into the pastels and spiders, of course to make bumble bees, and was curious how the "super pastels" I see around are made? Is it possible for me to come out with any super pastels from a spider and regular pastel cross?

Sorry, to get a super pastel, both parents must be pastels or genetic combinations that include pastel. The pastels that are commonly encountered have one pastel gene paired with a normal gene. Super pastels have a pair of pastel genes. So the only way to get a super pastel (AKA homozygous pastel) is to mate two snakes that each has at least one pastel mutant gene. This would be pastel x pastel, pastel x super pastel, or super pastel x super pastel.

>I have also heard about killer bees, and am guessing that is a super pastel-spider cross.....? Or is it possible for me to come out with killer bees from regular pastel-spider cross too?

Right, killer bees are a combination of spider and super pastel. You can't get one from a spider x pastel cross. One parent must be a bumblebee, and the other must be either a pastel or a super pastel.

>If someone can break down the ratios it would be great. I did read in a past message that from a super pastel you get all pastels, and no hets (something along that line....?).

This statement is half right and half wrong. All the babies from a super pastel x normal mating are pastels. The super pastel has two mutant genes (P//P, meaning a pair of chromosomes with a P, for the pastel mutant, on the left chromosome and a P mutant gene on the right chromosome). The normal has two corresponding normal genes (p//p, meaning a pair of chromosomes with a p, for the normal gene, on the left chromosome and another p gene on the right chromosome). Each parent gives one gene to each baby. The P//P parent can only give a P mutant gene, and the p//p parent can only give a p (normal) gene. The result is that all the babies are P//p, with a pastel mutant gene paired with a normal gene. These snakes are the pastels that most people have.

Where the above statement is wrong is that part about there being no heterozygous pastels. A heterozygous animal has a pair of genes in which the two members are not the same. In a P//p ball python, P and p are not the same, so these snakes are heterozygous pastels.

The reason for saying that there are no het pastels is because many herpers learned an incorrect definition for pastel. That definition is that the two members of the gene pair are different and the snake looks normal. A normal appearance is NOT part of the definition. The appearance of the heterozygous individual determines whether a mutant gene is dominant, codominant, or recessive to the normal gene.

A mutant gene is recessive to the normal gene when the heterozygous individuals look normal. Example -- albino in the ball python.

A mutant gene is dominant to the normal gene when the heterozygous individuals do not look normal. Instead they look like individuals with two identical copies of the mutant gene. There aren't any really good examples in snakes; salmon in the boa constrictor and striped in the California king snake are about the best.

A mutant gene is codominant to the normal gene when the heterozygous individuals do not look normal and do not look like individuals with two identical copies of the mutant gene. Example -- pastel in the ball python.

>So that would mean that from a super pastel-spider cross I would get 1/4 bumble bee, 1/4 super pastel, 1/4 spider, and 1/4 killer bee........???? Thank you very much for your time and I am looking forward to the responses!

Sorry, no. A super pastel has the gene pairs P//P s//s where P is the pastel mutant gene and s is the normal version of the spider mutant gene. A spider is p//p S//s, where p is the normal version of the pastel mutant gene, S is the spider mutant gene, and s is the normal version of the spider gene.

If you mate a P//P x p//p, all the babies are P//p, making them pastels (AKA heterozygous pastels).

If you mate an S//s x s//s, you expect half the babies to be S//s (spider) and half to be s//s or normal.

Put the genes together, and you expect
1/2 P//p S//s (bumblebee)
1/2 P//p s//s (pastel)

The easiest animals to get to make a killer bee are a pastel (P//p s//s) and a bumblebee (P//p S//s).

P//p x P//p --> 1/4 P//P, 2/4 P//p, 1/4 p//p

s//s x S//s --> 1/2 s//s, 1/2 S//s

Put the genes together, and you expect
1/8 P//P s//s -- super pastel
1/8 P//P S//s -- killer bee
2/8 P//p s//s -- pastel
2/8 P//p S//s -- bumblebee
1/8 p//p s//s -- normal
1/8 p//p S//s -- spider

Hope this helps.

Paul Hollander

I wrote:
>The reason for saying that there are no het pastels is because many herpers learned an incorrect definition for pastel.

Correct version:
The reason for saying that there are no het pastels is because many herpers learned an incorrect definition for *heterozygous*.

Sorry about that.

Paul Hollander

Thank you VERY much. Your post was more than I expected and I am actually printing it out to read it over again to make sure I got it right. Thank you again!

One last question:

How did you come to the conclusion of the pastel and bumblebee cross? I see you have it split into eighths, and I was wondering how you got to that point?