>I guess we are looking at the bell curve again in terms of color, behavior,
>etc. I suppose on the side of most of us that have only seen them in a
>tank several generations removed from the wild, it is difficult to select
>for the ideal norm fish from the wild. I wonder if there is a way to
>write "spects" for the "ideal" fish in terms of body proportions, color,
>etc. I have been told that the melanotonaids change in the artificial
>environment, even if they started as wild caught fish, they seem to change
>in terms of body proportions (adbdomen compressed, etc). Is this more an
>environmental (nature vs nurture) response that is not genetic (i.e. fancy
>guppies or swordtails raised in large ponds never really acquire the wide
>delta tails found in the same strains raised in small tanks.
All we have are pictures to go by and the original descriptions if we
don't start with wild specimens. And many pictures can be very
deceptive. Some changes are very easy to see, if the body starts
getting really broad and stunted. I've seen this in some of the M
affinis I've raised and culled them out. I think mainly in rainbows
we're looking at lose of color rather than increasing color. And color
enhancing foods can greatly effect this. But if you get a fish with a
differing color pattern then just don't breed it. Another thing I see
is the scales not lining up. They end up in a criss cross pattern down
the body rather than nice even rows. I suspect this may be cause by
limited calcium as fry but cull any regardless. I guess the same
problem occurs with apisto keepers. But those breeders are often
trying to enhance the colors, purposely picking out the most colorful
specimens and in a few generations they don't even resemble the wild
type. I was talking to a fellow up in Canada that keeps P furcatus. He
noticed a deformity occurring in the dorsal fin of most of his fish.
He told me it took numerous generations but he rarely sees this
problem now. Just a few examples here, but basically get to know your
fish. And rember how they looked when you got them. Then try to keep
them that way. You may find you're picking out the most colorful males
to maintain the color in the fish, because it seems to be fading. But
don't pick out only the most red fish because you think they look
better. There are often black lines, color spots or what ever to keep
track of also. When you really get to know your fish these things will
stick out, in particular when they're different.
later
Cary Hostrawser
My Rainbowfish Home Page
http://pw2.netcom.com/~caryho/home.html
Rainbowfish Study Group Web Page
http://home.stlnet.com/~gwlange/rainbowfish.index.html