Fwd: Re: [TAXACOM] genetic vs morphological trace of phylogeny

Derek Sikes dsikes at UCALGARY.CA
Fri Apr 9 16:11:53 CDT 2004


John,

I think the question of whether DNA data can be considered "cladistic" can
be simply answered by reading papers published in Cladistics, the top
journal of the field 'cladistics'.

If one were to do this, one would notice that a large percentage of the
papers deal with DNA data. I'm sorry, but there is *absolutely no question*
about whether DNA data can be used in cladistic analyses. None. Anyone who
thinks otherwise cannot be a practicing systematist.  There are differences
between morphology & DNA, yes, but as I've said before, both types of data
can be analyzed the same way and often are - using parsimony, and now
(>2001) maximum likelihood.

Taxacom is a good place for expressing views, exploration of ideas and
learning from each other. But I'm wondering if learning is actually
happening...

Yours,
Derek

> In response to Curtis Clark,
>
> It just so happens that some of my views on molecules and cladistics are
> in agreement on what some molecular people and some cladists also say, and
> then they differ with others. As for cladistics, I've certainly had plenty
> of time to tackle the subject and my views do correspond with the
> 'textbooks' (and the works of Rosa, Hennig, and Nelson) with respect to
> morphology, so your contention does not make sense in this respect. The
> only matter that is problematic is whether DNA sequence data can be used as
> cladistic data or not. Some on this list say yes, some say no. I currently
> lean to the latter.
>
> When I got into panbiogeography I was dismissed as not knowing what I was
> talking about because the panbiogeographic approach was 'refuted' by
> everyone and it wasn't supported by the textbooks.
>
> These things don't really matter in the long run. TAXACOM is a place o
> explore ideas as much as anything.
>
> john Grehan
>
> At 08:54 PM 4/7/2004 -0700, Curtis Clark wrote:
>> At 02:25 2004-04-07, John Grehan wrote:
>>>> I guess I'm a bit dense as I cannot make sense of your morphological
>>>> characters.
>>
>> John, a lot of us on the list keep our "mouths shut" about panbiogeography
>> because we don't really know anything about it. I'm starting to wonder if
>> you might not best do the same with cladistics. A lot of this stuff is
>> basic information in textbooks, and has been around for twenty years or
>> more. I could accept that you might not have time to tackle the subject
>> (that's my current excuse for panbiogeography, especially now that I know
>> that I won't be teaching the biogeography course), but it seems so central
>> to your human/orangutan arguments that it seems you would want to get it
>> right.
>>
>>
>> --
>> Curtis Clark                  http://www.csupomona.edu/~jcclark/
>> Web Coordinator, Cal Poly Pomona                 +1 909 979 6371
>> Professor, Biological Sciences                   +1 909 869 4062
>
> Dr. John Grehan
> Director of Science and Collections
> Buffalo Museum of Science
> 1020 Humboldt Parkway
> Buffalo, New York 14211-1293
> Voice 716-896-5200 x372
> Fax 716-897-6723
> jgrehan at sciencebuff.org
> http://www.sciencebuff.org/biogeography/Panbiogeography/Panbiogeography-Gate.h
> tm
> http://www.sciencebuff.org/HepialidaeGate.htm
>

++++++++++++++++++++++++++++++++++++++++++++++
Derek S. Sikes, Assistant Professor
Division of Zoology
Department of Biological Sciences
University of Calgary
2500 University Drive NW
Calgary, Alberta, Canada, T2N 1N4

dsikes at ucalgary.ca
http://www.bio.ucalgary.ca/divisions/zoology/sikes.html
http://www.ucalgary.ca/~dsikes/sikes_lab.htm

phone: 403-210-9819
FAX:  403-289-9311

"Remember that Truth alone is the matter you are in Search after; and if you
have been mistaken, let no Vanity reduce you to persist in your mistake."
Henry Baker, London, 1785
++++++++++++++++++++++++++++++++++++++++++++++




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