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BOUNCE killietalk at aka_org: Admin request of type /\buns\w*b/i at line 7
I apologize for joining the thread late, after not having really read it
as it developed, and I hope I'm not repeating someone else's
speculation. What occurs to me is this: in Apistogramma cichlids, it's
been proven that sex ratio is controlled by environmental factors, and
can be manipulated by temperature. We also see these late changes in
sexual characteristics in killies/livebearers. Could it be that gender
in fish can be an unstable thing, and that the hormonal balances
determining sex can simply break down as a symptom of aging? It doesn't
have be an evolutionary advantage/disadvantage thing. It may not even
manifest itself in nature, due to predation.
I have no scientific background -I'm just thinking out loud.
BizEcology at aol_com wrote:
> > In an evolutionary sense neither would make much sense, since if she's
> > breeding age, there's no way selection could ever operate on a sex
> No, no, no... you miss my point. The female changes to male
> functionality. That way the males do not see her as a mate and do not waste
> time chasing her. I have seen old female swordtails develop swords many
> times. they never breed again, nor do they chase females. They just get
> left alone.
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