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Re: Sex change in fish
BizEcology at aol_com wrote:
> I have read in the past about apparent sex changes in a number of fish. One
> of the theories is that female beyond breeding age have changing to male
> appearances serves two purposes:
> 1. The female gets left alone, since males will not be chasing her for
> 2. Males will not waste effort in a futile attempt to mate with a female
> incapable of producing viable offspring.
In an evolutionary sense neither would make much sense, since if she's past
breeding age, there's no way selection could ever operate on a sex change.
However, if being female requires more energy investment, switching to being
male when worn out may help squeeze the last bits of potential reproductive
success out of a long life. More likely sex switching derives from the simple
fact that the rarer sex has the higher fitness except in some situations, such
as when one sex keeps harems.
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