Re: [Killietalk] re: F0 designation

[Tyrone Genade <tgenade at gmail_com>]

Hello Brian et al


On Mon, 01 Nov 2004 09:34:40 -0600, Brian R. Watters
<bwatters at sasktel_net> wrote:
> Kyle Osterholt wrote:

> Hybridisation is regarded by some scientists as a valid way of determining

Hybridization can be very informative. Scheel's work clearly shows
that *gardneri* and *nigerianus* were distinct. Likewise he pointed
out many cryptic species among what is today *Chromaphyosemion*.  Very
often the minor details different species use to tell each other apart
are invisible to our eyes and hybridization can reveal these hidden
barriers.

> Nothobranchius will produce viable eggs when crossed and these may produce
> F1 hybrids. If the two populations represent the same species then viability

I'm told that guentheri and korthausae produce viable crosses up until
at least the 6th generation! But by then they are uninteresting muddly
little fishes. Sometimes hybridiztion is meaningless as the genetic
barriers may not of formed and the fish reply rather on geographic and
colour seperation to keep the species seperate.

Not really trying to start a debate... just thought I would share.
There are so many ways for for species to differentiate. Hybridization
is just one tool used to tell differences but it can't be used alone.

tt4n
-- 
Tyrone Genade
http://tgenade.freeshell.org
email: tgenade at freeshell_org; MSM: tgenade at hotmail_com
******************************************************************************
Instituto di Neuroscienze
Area di Ricerca del CNR via Moruzzi 1
56100 Pisa, Italy
http://www.in.pi.cnr.it/
******************************************************************************
All things work for good for those who love the Lord --- Romans 8:28

To join the AKA see http://www.aka.org/pages/join.html
Archives are at http://fins.actwin.com/killietalk/