Het question

[RondaH]

I am just getting into ball morphs and am still learning. If you breed a 66% possible het to a 50% possible het is there any way to know the chances of the offspring being het? Are the chances greater than the parents or less? Thanks for any info.

[RandyRemington]

Good question.

On average, if you paired a large number of 66% hets to a large number of 50% hets about 2/3 X 1/2 = 1/3 (i.e. 33%) of the time both would be hets. But you still need to get lucky enough to hit on the 1/4 chance per egg of producing a homozygous to know that they are both hets (I assume we are talking recessive hets here, even pastel's produce possible het eggs, it's just that as soon as the eggs hatch you know if you hit your odds or not).

So your best case is that you produce a homozygous visual and then know that both of your parents are het and all the normal looking siblings are 66% chance possible hets. Here is a baby I hatched this year for my 2nd time to hit on 66% het X 50% het:



I like those 66% odds so well I'm planning to keep two of her 66% chance het albino sisters too (they are all also 33% chance het stripe but that’s a whole other discussion).

Now it's when you don't hit on producing a homozygous visual that things get squirrely. Did you miss just by luck or is one or both of your possible het parents not a het? There is probably some way to weigh the odds depending on the number of eggs that missed but that's beyond what little I know about statistics.

MAYBE (and I'm quite possible wrong here) you could say that since your parents had a 1/3 chance of both being hets and since the normal looking offspring of hets are 2/3 chance hets that if you randomly picked a normal looking offspring from a large group of offspring from 66% chance het X 50% chance het that it would be a 2/3 X 1/3 = 2/9 chance het. But that doesn't factor in that if you had hatched 100 non visuals from a particular pair that almost surely one wasn't a het and the best you could hope would be for the babies to be 50% chance hets and given the odds of the other not proving they would probably be either 1/4 or 1/3 chance hets. But be it 1/3, 1/4, or 2/9 that doesn't make a lot of difference so the odds on a possible possible are fairly low. But my attitude is if you where going to keep a normal instead you might as well pick your favorite possible het and at least have a chance. I’m also keeping back two pastel 66% chance het hypo girls. Odds are only 1/9 that I’ll miss and neither be het hypo. Hmmm, if I keep a third that would be down to 1/27 and with four 1/81 but odds are my wife would shoot me before I got them all grown up and producing eggs, lol.