HYB: Fun with Punnett squares

Bill, that link was a delight.  Thank you!
 
When Punnett squares *really* get to be fun is when one deals with tetraploids.  Instead of a 2 x 2 box, we have a 4 x 4 one with sixteen cells.  Then, oh my, then, when you are dealing with two factors together, you end up with a 4 x 4 x 4 cube with 64 genotypes.  The more one tosses in the pot for analysis, the more the complexity grows--exponentially, just like with computer numbers  256, a kilobyte, etc.
 
The problem is, the assumption that the "gene" involved is simple isn't true.  It's just shorthand.  The "gene" is a process of many steps in most cases, any one of which can have alternative outcomes.  A case in point--we have a sequence, a simple one at that, of blues and whites.  At one end is the Dominant White that used to be "I" (now we're to think in a different, integrated set of terms, but I can't keep them straight, despite rereading that section of TWOI).  Then there's "B" (or used to be) then there are three different "w's"  w-sub-1, w-sub-2 and w-sub-3, then to make things interesting, the side-branch that takes us off into PL-land with about six or so alleles, I think (used to be only about three until Splashacata and some others came along), and another side-branch that deals with I-sub-s describing the sequence from KEVIN'S THEME to the EMMA COOK/QUEEN'S CIRCLE type.
 
Now *that's* simple.  If you want to get complicated, just try predicting the outcome of crossing two of Barry Blyth's babies.
 
Theoretically, at least, it could be done, but it would take one of those Cray computers they use at Lawrence-Livermore to crunch the numbers.
 
Neil Mogensen   z 7  in western NC

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