[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Hybrid sunnies (fwd)

Hehe.. I take it back Dave, you did send to the list too. :)
Message below the sig. 

J. L. Wiegert
 Dubotchugh yIpummoH.                      bI'IQchugh Yivang!
Native Fish Conservatory Mailing List (NFC at actwin_com) Administrator. 
The list is also available in digest form (NFC-Digest at actwin_com). 
To subscribe to this list, send mail to Majordomo at actwin_com with the
command "subscribe nfc" or "subscribe NFC-Digest" in the body.  To
unsubscribe, send mail to Majordomo at actwin_com with the command
"unsubscribe nfc" or "unsubscribe nfc-digest" in the body.  Feel free to
ask for help!

---------- Forwarded message ----------
Date: Sat, 03 Oct 1998 22:17:02 -0400
From: David E. Boruchowitz <editor at tfh_com>
To: nfc at actwin_com
Subject: Re: Hybrid sunnies

>Some very good and interesting points.  I wasn't aware that the male

>contrubute anything at all in teh Amazon Molly.  However, it makes

>since only some species of males (erm, you know what I mean) will

Well, the evidence only suggests this--more research is needed.

>Many, many, species will hybridize in captivity that just don't seem 

>"want to" in the wild.  Its interesting, but, in cichlids I've bred,

>often had an individual refuse a mate of his own kind and instead take

>another.  Mind you, the other species was not introduced before the

>prospective mate.  Weird. :) 

We forget that there are a lot of things floating around in that
transparent water in our tanks. One is pheromones. I remember seeing a
film clip of two species of gourami, kept in interspecies pairs. Nothing
happened. THen the opposite sexes of each species were placed into an
aquarium which shared a common filtration system with the aquarium
housing the mixed pair--they spawned and had viable young! (The fry grew
up to look like Ctenopoma!) I think this is often involved in aquarium
hybridization. I wish I'd been smart enough as an undergraduate to record
the citation for this study, since I've never seen it again. Anybody know

>I was aware that hermpahrodites are not uncommon.  However,

>hermpahrodites in the fish world are very uncommon. AFAIK, the two

>rivulines are teh only ones which can do it.  Also.. I don't believe

>R. marmaratus ever fertilizes its own eggs...  I just thought it

>gametes with another.... I'd like to hear any other info you may have


In February of this year we ran an article:

<bold><fontfamily><param>Times New Roman</param><bigger>Sex and the
Single Killifish

Kathleen S. Cole</bigger></fontfamily></bold><fontfamily><param>Times New
Roman</param><bigger>, Associate Professor, Department of Biology,
Bishops University

<bold>David L.G. Noakes,</bold> Professor, Department of Zoology and
Axelrod Institute of Ichthyology, University of Guelph


In it they cite scientific proof that marmoratus is the only VERTEBRATE
known to practice self internal fertilization.

>Another weirdo in the fish kingdom I thought of:  The four eyed fish:

>Which can only mate with individuals of the other orientation.  The

>sexual organs are located one one side.. so a left orientated male can

>only mate with a right orientated female.  Truly odd order.


This was one of my favorite examples. Until I came across claims that it
isn't so. Those who refute the established notion claim that the
gonopodium's mobility makes up for its "handedness." If true, it blows
this one up, but the fish are still incredible in having a dual
retina---and the one-sided sex organs, even if they're limber enough to
get around that!  :)



David E. Boruchowitz

Editor, TFH Magazine

editor at tfh_com