Genetics are VERY specific about the outcome of Heterozygous breedings. Punnett Squares give you EXACTLY what should come out in a perfect situation. However... these predictions' accuracy is NOT based on entire clutches. The predictions are based on EACH EGG and it's probability of being a certain homozygous form.
You may get one DBl Homozygous out of a 16 egg project... you may not. Remember statistics are ALWAYS accurate when you count massive numbers. For instance... from 160 eggs you hatched around 10 Dbl Homos... that is more like it. Even MORE accurate if you hatch 1600 eggs and you get around 100 Dbl Homos!
Just because you hatch 16 eggs doesn't mean that ONE of them HAS to be a Dbl Homo.
Here is a bit of controversy for you... I may get reamed over this one... This illustrates my explanation of genetics based on each egg (embryo)...
Possible Hets... some say (no offense meant to you) that it is more advantageous to hold back siblings because it nearly guarantees you to have Hets by probability. This is false! For this to be true then Punnett Squares have to be accurate to clutches.
For example... you breed a Het male to a Normal female to make 50% Possible Hets. She lays 4 eggs and they are all female! (perfect world huh?) You think by holding back all 4 that your chances are better of having 2 100%ers than if you saved 1 50%er from each of 4 different clutches. THERE IS NO DIFFERENCE. For there to be a difference, our punnett square has to control the entire clutch, which it doesn't. We are NOT guaranteed to have 2 Hets and 2 Normals in that 4 egg clutch. We are however guaranteed that each of those 4 eggs has a 1 in 2 or 50/50 chance of being a Het.
Think this is BS... call your local Geneticist!
This works the same way... Ralph got a clutch of 4 eggs from Dbl Het x Dbl Het (Jolliff Line) in which the results were ONE OF EACH... 1 Axanthic, 1 Albino, 1 Normal, 1 Snow! This just shows how everything in genetics is just chance. He was NOT guaranteed to get 1 Snow out of 16 eggs but he WAS guaranteed that EVERY SINGLE EGG had a 1 in 16 shot of being a Snow!
On a side note... when did ANYONE EVER say a SNOW was going to be WHITE?!? I have only seen maybe 2 Axanthics that were actually that silver/gray color as adults!! Most all Axanthics are some form of Brownish/Gray... remember... they still have Erythrophores... gotta get that red out too!
Snow Boas, Snow Corns, Snow Honduran Milksnakes... etc... NONE are WHITE!! And unless you actually go in an kill all of those little Chromatophores... it will NEVER be as white as the white on a PIEBALD or a LEUCISTIC. They just don't have the skin cells to make the pigment show up PERIOD! Albinos and Axanthics do..........
And that's all I have to say about that...
Thanks for reading...
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Sean Bradley
Owner : EbN
www.ExoticsByNature.com
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