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RE: Using Punnett Squares?
The typical presentation of Punnett Squares presumes full, accurate knowledge of the genetics of the parents and aids producing the possible offspring, and the probabilities of each.
With KittyCatS, however, we rarely have full, accurate knowledge. In addition, we're often reversing the question: attempting to determine the genetics in the parents from the observed offspring.
Punnett Squares are one of the representational forms which can help with both questions. There are others. Functionally, all are equivalent. Punnett Squares simply are more useful for those who do better with a graphical representation.
Whichever form you chose for your analysis, you should always remember that you're dealing with "unknowns". While, many times, your analysis can produce a definitive answer, providing a hard value, converting an "unknown" to a "known", most often the best you can do is identify limits and make probabilistic statements.
For example, let's take a Red Tabby with an unknown recessive (hidden) fur and cross it with a Ebony Black Silver, also with an unknown fur.
If the offspring is Red Tabby, we learn nothing. Punnett Squares tell us to expect this half the time.
If the offspring is Burmese Platinum, Punnett Squares tell us it can ONLY have come from the Red Tabby, and that we can expect this the other half of the time. In addition, we've converted the "unknown" for the Red Tabby to a "known": it hides Platinum and cannot hide anything else.
If the offspring is Ebony Black Silver, Punnett Squares tell us we've learned a bit: the Red Tabby cannot hide anything more dominant than Ebony Black Silver. While this does not convert the "unknown" for the Red Tabby to a "known", it does allow us to make a limiting statement: the Red Tabby must hide Ebony Black Silver OR something more recessive.
Finally, if the offspring is Balinese Cream, we learn something about both parents. We still have not converted any "unknowns" to "knowns", but Punnett Squares tell us that BOTH parents must have a recessive (hidden) of Balinese Cream OR something more recessive. They tell us ONE of the parents hides EXACTLY Balinese Cream, but do not indicate which (the other may hide Balinese Cream, as well, but might hide something even more recessive). In this case, we're able to make limiting statement about both parents: they hide Balinese Cream OR something more recessive.
It's also good to apply the knowledge gained to the offspring. Those offspring who were NOT Red Tabby, cannot EVER hide Red Tabby. Unlike some other breedables we see on Second Life, it is completely impossible for those offspring to EVER pass Red Tabby. Quite simply, if they had carried the Red Tabby gene, they would have BEEN Red Tabby. So, if we want Red Tabby from those offspring, we'll need to locate a mate for them which CAN (or does) carry Red Tabby. Yes, you can say they have Red Tabby in the background, but that means NOTHING to their potential offspring. Unlike those other breedables, KittyCatS *NEVER* "reach back" to pull out something more dominant which was lost.
Of course, this is all well and good when we're looking at just one pairing, and their offspring.
Things get a lot more complex when we take those cats to other pairings.
For example, let's say we actually had those parents produce a Balinese Cream. Let's take that Red Tabby (who we now know hides Cream or better) and cross it with a Blue Tabby. Say the offspring is Bengal Snow. This tells us that the Blue Tabby hides Bengal Snow, exactly, and nothing else! Why? Because Bengal Snow is not Balinese Cream, and it's not Red Tabby, and it's not recessive to Balinese Cream .. so it cannot have come from the Red Tabby .. it can only have come from the Blue Tabby.
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