Posted by Greg on October 06, 1999 at 22:31:27:
In Reply to: Wow, This is COMPLICATED! posted by Clarissa on October 06, 1999 at 21:58:03:
: Here's the rundown:
: 1. I inbred 6 generations (the original fish count as f1) of German Tuxedo --
: starting with a Yellow-tailed male -- until all the male offspring were dark
: yellow.
: 2. I inbred 7 generations of Red-Tails until all male offspring were Cherry
: Red.
: 3. Using females from the last generation of Cherry Reds and males from the
: last generation of Dark Yellow Tuxes, I crossed the 2 strains. A large batch
: (15 fry: 6 M, 9 F) yielded males that were ALL a color combo I'm calling
: "Sunfire": rich yellow tail with tinges of orange and a bright light blue
: peduncle.
: 4. I inbreed 4 of the Sunfire males with 4 of their siblings. The results?
: Hang onto your hats!
: Out of 8 batches of fry, I matured 2 to get a reading on where this cross was
: going. The two batches totalled 11 males. Here are the traits displayed:
: (1) male is SILVER
: (1) male is SILVER TUX
: (1) male is PINK w/BLUE peduncle (like in the photo)
: (1) male is SUNFIRE
: (2) males are SUNFIRE TUX (one in each batch)
: (2) males are BLAZE TUX (a fire-engine red, one in each batch)
: (3) males are FLAME (like Sunfire, only deep orange w/blue peduncle)
: I make FIVE tail colors there. How can that be? If you do the punnet square
: thing, shouldn't there only be FOUR possible combinations?
: Gosh, I'm really over my head here . . . .
: Greg, you understand the theory very well. Do you have any idea what I'm
: dealing with here?
: Thanks,
: Clarissa
My first impression here is that we are dealing with more than one gene for tail color. I call it my "RGB" theory.
What I think (and this is just a theory) is that tail color is controlled by a number of genes which display incomplete dominance. Out of the "Aquazone box" I have noticed 3 shades of red in the Red Tails and also 3 shades of yellow in the Yellow Mosaics.
What I am guessing is going on is that a different "shade" of a color is showing up depending on if a gene is AA, Aa or aa.
What I am also guessing is that there is also more than one gene that controls the overall color. It's the combination of several genes that control the overall output.
For those of you into computer theory, you'll remember that the simple answer for explaining the color of a pixel or dot on your monitor is that it is controlled by 3 numbers representing red, green and blue. Each number can be 0 to 255 and would represent a shade of red, green or blue. The combination of the three yields over 16 million colors.
My "RGB" theory is that there are a set of genes. I don't know how many or what colors they control, but let's say there are genes for red, yellow and blue, since those come up a lot.
There would be three possible shades of red, three possible shades of yellow and three possible shades of blue. If that were the case, you would get thousands of possible colors. We know that AZ is only a 256 color program, so many of them would look alike.
An example:
If you had a guppy with an AA code for all three tail color genes (i.e. dark red, dark yellow and dark blue) the outcome might be black.
If you had a guppy with an aa code for all three tail color genes (i.e. light red, light yellow and light blue) the outcome might be white.
Clearly, a lot of study and research is yet to be done before we understand how the genetics work and how color is transferred from parents to fry. As a computer programmer though, this is how I would do it.
-Greg