Reptile & Amphibian Forums

As I posted before, I'm getting a few Bulls from Dan Felice. I've been away from snake genetics since I bred to create my own Snowcorns in the mid 80s, so I'm kind of rusty. Dan is curious about this every different hatchling from a recent clutch that I'm getting from him. ( feel free to add in Dan if I'm misunderstanding some of this lol )

My understanding is....

One of these ....

Was bred to one of these...

Which produced these...

(Baby pic )

( Adult pic )

And two of the above bred together produced these...

This is the only time Dans animals have produced a very light animal like this. If I'm understanding correctly, the mating of the Stillwater x Crumbley produced babies intermediate in looks between the two strains with a simple recessive for the Stillwater Type Hypomelanism carried by all the young but not displayed. ....

But when these babies were raised by Dan and bred together, they produced young looking like the parents except for the very light one because it displays the recessive gene for Stillwater type hypomelanism that both parents carried.

If that's also the case, why wouldn't there normally be more light ones produced? Also the light on is VERY much lighter than my baby SHBS from this year, why is that do you think?

( I used one of discerns and a goggle image to show what the originals might've looked like, not my pics )

Someone better with genetics please correct me if I'm wrong on this, but to my understanding, there isn't a simple recessive with bulls. Both parents have to carry the gene for it to show up visually. So the clutch from the original cross would look "normal" with a 66% chance of having the hypo gene. Obviously he picked two that did indeed have it. So theoretically 1 out of 4 should be hypo. If you "roll the dice" on those odds, you could produce many normal babies before hitting the one hypo, or you might luck out at times and get above the expected out come. It's just the difference of theoretical (what SHOULD happen) and experimental (what DOES happen) probability. Take a die and roll it 6 times, and see how many times you come up with a certain desired number.

As far as the color difference... Hypos are highly variable, and go through drastic color transformations from hatching until adult hood. My two are one year,and a 2013 model, and both don't look like the same snakes I first bought. They are awsome creatures though.

In my opinion,you're right on the mark about the statistical odds as they relate to somewhat unexpected percentages of expressive offspring.it may have just been a less than favorable roll of the proverbial "dice"....however,all of the commonly seen genetic traits currently known to us as hobbyists in regards to "Sayi "are in fact simple recessive.(with the exception of "red" & "yellow" respectively.) and the initial breeding would've produced offspring that were 100% het. for the Stillwater form of hypo,the 66% possible hets. come in the following generation,(from breeding two het. siblings.) all of the offspring from that breeding that are not hypos themselves,are said to have a 66% probability.(essentially 2 out of every 3 normal looking babies should be heterozygous.) I also think you are right about the variability of expression seen in hypos...no single genetic mutation works in a vacuum,when expressed,there are also a potential multitude of other genetic influences at work and sometimes several generations must be produced to understand exactly what's going on.

I appreciate the post.

As I said, its been a long time from the days of the Amel. Corns. Since that time I've worked with different animals and haven't been much for mutations.

It's a different world now in the hobby with Ball pythons . I see people throw around the word "co-Dom" and a million little subtle differences that I really honestly don't pay much attention to. Lol.

That was my understanding too of the "Yellows" and "Reds" , that its not a recessive trait , just animals that are inclined to have background washes of yellow or Red that can be enhanced by possibly breeding the brightest animals together. Much like we tend to selectively breed the blackest Lodingi in the hobby to get the darkest animals. I guess that's the case too with the ultra refined Abotts strain Oakatees , boy I wish I lived in a state where I could work with normal Corns!

There's something about those SHBs that I find really attractive . I'm still not much into Mophs but there's a certain something about that subtle but beautiful decrease in melanin.

I feel the same way about the Stillwater animals! That's actually what got me started again with the colubrids.the first time I saw one I was hooked!