For those of you with an interest in DNA studies and where they are going
(even if we can't afford it - yet), here is a recent paper by Tom Duda (from
this LIST) who is probably too modest to put his hand up. Tom and colleagues
used DNA sequence data from mitochondrial and nuclear loci of 76 Conus
speices to generate species-level phylogenetic hypotheses for this genus and
then mapped known diets onto the pylogenies to elucidate the origins and
evolutionary histories of different feeding specializtions. Still interested
? Read abstract below...then go to the library for the full article.  Nice
work Tom!
Bruce

Duda, TF Jr(1)*, Kohn, AJ.(2) and Palumbi(1) SR. (2001) Origins of diverse
feeding ecologies within Conus, a genus of venomous marine gastropods.
Biological Journal of the Linnean Society (2001), 73: 391 - 409.
(1)Department of Organismic and Evolutionary Biology, Biological
Laboratories,Harvard University,USA, and (2) Department of Zoology,
University of Washington, Seattle, USA
Abstract: Specialized predators on polychaetes, fishes, hemichordates or
other molluscs, members of the predominantly tropical gastropod genus Conus
diversified rapidly during the Miocene to constitute the most species-rich
modern marine genus. We used DNA sequence data from mitochondrial and
nuclear loci of 76 Conus species to generate species-level phylogenetic
hypotheses for this genus and then mapped known diets onto the phylogenies
to elucidate the origins and evolutionary histories of different feeding
specializations. The results indicate that dramatically new feeding modes
arose only a few times, that the most derived feeding modes likely arose in
the Miocene, and that much of the known diversity of Conus that was
generated during Miocene radiations has survived to the present. . 2001 The
Linnean Society of London
ADDITIONAL KEYWORDS:Gastropoda Conus molecular phylogeny feeding ecology
ecological diversification

----- Original Message -----
From: "Thomas E. Eichhorst" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Thursday, April 25, 2002 7:04 AM
Subject: Re: DNA question


> Hear, hear.  It will only be one small part of the puzzle.  And two
closely
> related species could well have very, very similar DNA.  Plus we have
heard
> before from the geology contingent about maintaining a connection with
> fossil species where DNA work is not possible.  Shell and animal anatomy
> must remain key to taxonomic decisions.  I guess the DNA can be one of
those
> clinching arguments; if the shells look different and the soft parts are
> different AND the DNA is different -- then they must be different species!
>
> Tom E.
>
> -----Original Message-----
> From: Conchologists of America List [mailto:[log in to unmask]]On
> Behalf Of Monfils, Paul
> Sent: Wednesday, April 24, 2002 10:33 AM
> To: [log in to unmask]
> Subject: [CONCH-L] DNA question
>
>
> DNA sequencing is often spoken of as though it is the "final solution" to
> questions of taxonomic placement.  I can see that such studies might
reveal
> high-level relationships (or lack thereof) that might not be expressed in
> morphology.  For example, it might reveal that a shell currently
classified
> as a volute, because it looks like one, is actually a Marginella.
However,
> when you get down to decisions at the species or even subspecies level,
how
> is DNA analysis any more objective than morphologic analysis?  Once you
know
> the degree of difference between the DNA of two similar forms, doesn't
> someone have to make a subjective decision as to whether that degree of
> difference warrants specific separation or not?  And aren't we necessarily
> going to end up with a camp of taxonomic DNA lumpers and a camp of
taxonomic
> DNA splitters, just as we have traditionally had with morphological
studies?
>
> Paul M.
>