Re: NANFA-- Rivulus reproduction

Klaus Schoening (sege7_at_earthlink.net)
Wed, 29 Dec 1999 05:35:16 -0800

Rivulus marmoratus does produce males also, so there is some sharing of genes.
The males can be identified by the bright red color in the fins. Though males are
somewhat rare, their existance does insure continued genetic diversity.
Marmoratus is a very successful species and is found all the way from Florida to
Brazil.

Shireen Gonzaga wrote:

> As a relative novice to the wunnerful world of fish,
> I was totally amazed when I read a piece about how
> Rivulus marmoratus reproduces. Self-fertilizing
> hemophrodites! Cool! (There are other species among
> molluscs and amphibians who do this too, right?
> But I never heard of it in fish!)
>
> What kind of genetic diversity is found in the
> offspring of a single fish? Are they clones of the
> parents? If so, how "old" is this species? I'm
> fascinated by the (probable?) absence of genetic
> diversity that would otherwise be present in
> sexually-reproducing species, and the natural
> selection effects that would have steered the
> evolutionary course of this fish.
>
> - shireen
>
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/ For more information about NANFA, visit our web page, http://www.nanfa.org