Reptile & Amphibian Forums

I just got 7 eggs from a 25% chance het albino girl yesterday. Looks like hatch in first week of December if all goes well.

This is by far the latest clutch I've ever had. I know they aren't all that rare and with so many ball pythons being bred now days I wonder if anyone will have a later hatch date in this calendar year.

Is anyone expecting eggs in the next 3 weeks or so? Maybe we could track the last and first hatchlings of each year just for fun.

Just curious. I know a fair deal about genetics and I completely understand 100%, 66%, 50% chance hets., but have never seen or heard of 25% chance hets.

Did you come up with that (25% chance) because one of the parents is a normal and another one is a 50% chance het? This makes some sense, but in reality, isn't one parent either a het. or not a het.?-thus making all of the offspring from that breeding either 100% normals or all of offspring 50% chance hets.

A 100% chance of the entire clutch being all normals or all being 50% chance hets. isn't quite the same thing as a 100% chance that 25% of the clutch will be hets. If so, 25% chance het. is really a bad term.

Congradulations on the late clutch!

Rodney

IMO
Forget the percentages. Everything should just be possible het. The percentages should only be kept in mind.

I thought I might catch some flak for “25% chance het”.

As you and everyone else who has posted a question about my use of “25% chance hets” has correctly speculated, I use the term to signify the offspring of a 50% chance het and a normal. Since I don't know if the 50% chance het father was a het or not I don't see a problem calculating the odds out another generation. We have already accepted "50% het" as a term when each is really either a het or not a het, we just don't yet know which. Sure all "25% hets" are either normals or 50% hets but since we still don't know which and out of a large pool of 25% chance hets from a large pool of 50% hets about 25% would be hets I think it accurately describes my odds as best possible with my limited information about the father. Actually, in this case, her and her at least half sister where produced by breeding several 50% possible het albino males to a group of normals.

The down side I see to the term "25% chance het" is that there is a 50% chance that the baby never even had a chance to be a het because it's 50% chance parent didn't hit it's chance. This is different than a 50% chance or 66% chance where you know for sure that the gene was there one generation back. Maybe I'm expecting too much for people to realize that a "25% chance het" is "the offspring of a 50% chance het and a normal" and understand the implications of this but "25% chance het" is just so much shorter I can't resist using it. I suppose a lot of people would even need a long explanation to fully understand the odds with "the offspring of a 50% chance het and a normal" anyway but since it looks like I'm going to have to write a dissertation defending the use of "25% chance het" every time maybe I should just come up with a paragraph explaining the situation in detail and go the thorough route instead.

Sorry, no offence intended, you have a valid point. I’m just a little grumpy working nights and writing code that never seems to work right during the day and my kingsnake breaks aren’t helping.

I was just checking to see if there was something that I wasn't aware of or something that I was missing. You know the saying, "If you assume, you make an a** out of you and me."

I don't really see a problem calling them 25% hets. It's just that there is a difference statistically from --a 50% chance they are all normals AND a 50% chance that that there is a 50% chance they are hets--and a pure 25% chance they are hets.

Thanks again,
Rodney

I see no problem with the 25% het term since afterall that's exactly what it is. It would be pretty cool to prove out a 25% het animal (and the price would be pretty fair also.) Personally I'm not much of a gambler so I'd of course much prefer a 100% het but if the price is comparable to a normal, why not take the chance? Good luck and I hope they prove out for you, Scott.
-----
Injustice anywhere is a threat to justice everywhere.
Martin Luther King, Jr.

"In any civilized society, it is every citizen's responsibility to obey just laws.
But at the same time, it is every citizen's responsibility to disobey unjust laws."
—Martin Luther King Jr

My question: What are the odds that a normal ball is a het?
There are several different ball morphs being imported to the USA every year. Many of them being ghosts, pastels, axanthics, pieds(mostly spots), and many more that have not been proven or are extremely rare. These are often found early, and sold for a higher price. They are hard to come by, but thousands of normal looking balls are imported every few months, and they could easily be siblings to these genetic mutations. I am not great with numbers, but the term "one in a million" comes to mind. I feel they are much more common in captive collections and wonder how many are out there and who has tried to prove a normal looking ball to be a het and found something cool? I think that out of all the ball pythons I have, at least one is a .01 het for ...........?
Evan

I've heard of several cases of presumed normal balls turning out to be unexpected hets. As more morph gene males are used in breedings these should be found even more often.

If hets for a particular recessive mutation are randomly distributed at 1 in 100 in the wild then they would pair together at 1 in 10,000 and produce 1 in 40,000 homozygous offspring. With 150,000 wild-bred hatchlings exported from Africa each spring 1 in 40,000 would work out to about 3 or 4 of each mutation with 1 in 100 randomly distributed hets. I think 3 or 4 per year from Africa is not that far off for several different morphs.

The problem is that I can't be sure about the random distribution assumption or how to account for localized inbreeding so the 1% het rate is probably a little high but based on the hets found through captive breeding so far maybe not all that high.

Here's why...
These days, not many people are breeding 'normal het for nothing'
males. Het males or poss het males are very affordable.
Every year, a ton of '25%' het males are sold as normals.
Afterall, it is hard enough to sell 50% het males. 25% het
males wouldn't command much more than just a normal male, so
people pretty much just get rid of their 25% het baby males.
The people who buy them usually just assume they are normals.
Most of the time, petstores that buy them will just advertise
them as normals.

So...all these 25% het males (and to a lesser degree 50%ers)
are out there and people don't know about it (they just think
they have normals). They raise them up and breed them to their
other normals (females). Well, over a large population of
25% het males, roughly 1 in 4 are actually hets! So, that means
that there are a lot of 50% het babies being born out there that
people just think are 'normals'. These get sold, and breed and
produce more poss hets, and so on, and so on.

That's why I think the number of people that will be getting
pleasantly surprised will be on the rise! It hasn't happened
to me yet...but I'll keep wishin'.

Good luck to all,
ChrisS - SanJose

PS: By the way, I fully support calling an animal a 25% het if
one of the parents was a 50%er. It especially makes
sense when you have multiple 50% het males siring several
clutches. Some of the males should be hets. Therefore,
statistically over a large group of babies produced by several
actual 50% het males each randomly selected baby will have
a 1 in 4 chance of being het. Thus: 25%. Enjoy!

I think I paid $80 for her back in 1999. I'm with you, why not at least get something with a long shot if normal price is all you can afford.

Earlier this year I hit on 66% het X 50% het so I know that "luck happens" and now my male is proven het for albino. Hopefully he will eventually also prove het Jolliff axanthic.

As far as keeping track of the actually percentages rather than just lumping all possible hets together – I find it useful to calculate the cumulative percentage of hitting on at least one when deciding how many possible het males to buy or how many possible het girls to produce or keep. If I could afford better odd animals (i.e. 66% chance) then I wouldn’t have to keep as many.