|
Update on Bizzare Gender Guppy
|
|
By Phry, Section Shows
Posted on Wed Aug 29, 2007 at 12:25:17 PM PST
Tags: (all tags)
|
 |
|
Unclescott reminded me of my previous post on my guppy of abnormal gender and my reference to Yamamoto. I have an interesting update on the gup, and can attempt to quickly summarize Yamamoto as well...
|
To rehash quickly: the guppy had no gravid area whatsoever, but had a flat anal fin (no gonopodium) at least one month after sibling males were definitely FULLY functional (retroactively evidenced by pregnancy) and quite a long while after said males had FIRST begun development of a gonopodium. 'He' was endlessly pursued and courted by males, but in turn found interest in courting females. 'He' had no body coloration like his sisters, but a very vivid tail with detailed patterning.
I referenced Yamamoto at the time, although I must admit that his work is extremely dense detailed genetic research, and was difficult to understand word-for-word :) The gist of the article I waded through was that guppies- besides having, of course, XX or XY chromosomes- have a 'secondary sex' if you will, and in some cases the secondary sex can affect the phenotype drastically and make a male have predominantly female characteristics, or vice versa. However, his work did not seem to apply because in the end, he stated that secondary sexual characteristics do not 'overwhelm' the fact that males have gonopodiums and females have gravid areas (reminds me of a line from Kindergarden Cop...)
However: update! Recently 'his' anal fin finally matured into a gonopodium. However, he is still endlessly harassed by males and their courting displays. Still, this is, perhaps, a situation I have heard about in a few scattered sources:
For those interested, I managed to recall and locate one small passage from "Ichthyology" by Lagler, et. al. "Sex-reversed males presumably bearing XX chromosomes have been noted in the guppy; their genetic sex was female, their real sex, male.... when one of these exceptional XX males was mated to an XX female, all the resultant offspring were females."
Which makes sense, since each can only obtain X chromosomes from either parent. I'm still not sure why the males love him so much nowadays, though, or why his development took so long. Has anyone ever had such a guppy before? Please share! :) If tank space permits (and I intend to make it work), I would like to go ahead and try to mate my 'male' just to witness the result and possibly get some closure- I'm dying from curiosity.
Phry |
|
|
Immediate Help
