I do know that there is also usually sexual dimorphism in brooksi when it comes to lightness, and the amount of yellow coloration too. So this could also have played out there as well.
Don't ever discount weird off-the-wall stuff that just happens from time to time, genetics sometimes doesn't need a reason to do things, it just does it with no rhyme or reason. This happened to me this year too with some nice non-morph brooks offspring.
This bizarre crazy looking youngster was produced by my nice yellow 100% floridana pair. It looks NOTHING like a typical brooksi whatsoever, but yet it is one, and it certainly happened.
~Doug
here's the parents(sib to sib breeding)

and here's the totally weird aberrant offspring(looks goini, but AIN'T). 100% brooks, 100% weird, and 100% cool!

here's another sibling of the above weirdo. If these were put on a table, and I told you these were siblings, you would say I was full of it, but indeed they are sibs.

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"a snake in the grass is a GOOD thing" 