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

Peter Unmack (peter.lists at)
Fri, 12 May 2006 13:13:55 -0500 (CDT)

G'day folks

You guys are grossly over exagerating certain concepts based on oddball
examples. Goldfish do good no matter what you do to them. They are also
polyploid ( ) which is thought by
some to give species a significant adavantage in certain situations. It
could go some ways to explaining why they are so adaptable.

To say that Devils Hole pupfish revert back to their ancestral form when
put in a different environment isn't correct either. Again, Devils Hole
is an extremely unusual environment, and that species is also extremely
unusual due to have lived in tiny place for a very long time. To put them
into a different environment and expect them to be exactly the same
ignores basic biological logic.

Additionally, you guys are talking about different traits that differ in
their levels of phenotypic plasticity ( ) and you can't really
compare their response in captive and introduced popultions. Morphology,
coloration and behavior are all massively different from one another in
terms of their genetic basis and variability and interaction with their
environment. You have to remember that phenotype = genotype x
environmental interactions. And many traits can differ within a species
even when there is no genetic variation and certain traits only differ
when there is genetic variation. But many are somewhere inbetween which
is what makes things so complicated because any change in environment can
also effect the phenotype. This variation in environment is what probably
causes many of the problems of captive versus wild raised fish.

Dealing with what issues determine the success and failure of species
introductions is extremely complex and goes well beyond the simple issue
of genetic variability. There can be a million things that can determine
success or failure. And there are always examples that will contradict
other examples.

Peter Unmack
Provo River, UT
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