Re: NANFA-L-- Re: the aquarium hobby as conservator of

Bruce Stallsmith (
Sat, 13 May 2006 19:44:14 -0400

You can get different phenotypes from the same genotype because of variation
in genetic regulation, what regulates transcription, translation and the
whole shebang of the transcriptome. Most of those details would drive people
off of any list, of course, and are poorly understood anyway. This doesn't
even take into account the effects of hormone regulation and production from
the same environmental influences (testosterone is my new favorite molecule
and I don't even play baseball, go figure). So as Peter has pointed out in
other contexts, we have lots of variables in play

The bottom line is you better have-in-least thousands of fish to release if
you want to have any left to grow and reproduce. I know that the CFI people
released about 1000 sub-adult boulder darters-in-one site in the Elk River
in Fayetteville, Tennessee as part of their breeding & release program, and
several other sites received about that many. They were all marked with
fluorescent dye, and two months later CFI people saw some marked individuals
at each site while snorkeling. I haven't heard further updates. But the
original population had declined due to environmental insults, not predation
by an exotic, so maybe there's more hope for this darter than for many other

--Bruce Stallsmith
along the Tennessee
Huntsville, AL, US of A

> I was taught that what you speak of is pheno types
>showing up under different enviroments. I bet if they
>did genetic test on the fish the genes would be the
>same. Genes do not change in one generation from the
>wild caught fish. They may look totally different
>because of the different enviroment but genetic
>changes take time.
> Later, John
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