Archaeopterygid bird from China

[Robin Leech]

I cannot agree with Robert that we systematists exclude geographical
information.  We need it, and we use it.  In fact, some of us use it in
keys.
Robin Leech

----- Original Message -----
From: "Karl Magnacca" <kmagnacca at WESLEYAN.EDU>
To: <TAXACOM at LISTSERV.NHM.KU.EDU>
Sent: Friday, April 01, 2005 9:16 PM
Subject: Re: Archaeopterygid bird from China


> On 2 Apr 2005 at 8:05, Robert Mesibov wrote:
>> Systematists s.s., on the other hand, especially in the last 30 years,
>> have
>> rigorously excluded geographical information from their thinking.
>> "Location"
>> is never, ever among the list of characters drawn up for a phylogenetic
>> analysis,
>
> I'm not sure this is necessarily a bad thing.  I haven't thought deeply
> about it, but I think you could make a pretty good argument that there
> isn't an expectation of "homology" for things that live in the same
> area.  Moreover, you would have to use the pre-defined areas you seem to
> disparage; otherwise you get into the morass of overlapping
> distributions, like a quantitative character.
>
>> and no phylogenetic software package includes algorithms for
>> raising a skeptical eyebrow at patterns that make no geographical or
>> geological sense.
>
> I think a program like DIVA would at least tell you (after it's worked
> out) whether your tree makes sense.
>
>> "Centre of origin" thinking in 2005 is similarly after-the-fact. It's a
>> belated attempt to root character-based phylogenies in geographical
>> reality.
>
> I don't understand what you're arguing for here.  I assume you're not
> supporting determining center of origin before the fact, but somehow
> concurrent with phylogenetic analysis.  But how could you actually do
> it?  Attaching an address to branching events is simply a matter of
> character optimization (which, of course, makes it wholly dependent on
> the structure of the tree), but it sounds like you want more than that.
>
> Karl
> =====================
> Karl Magnacca, USGS-BRD
> PO Box 11, Hawaii Natl. Park, HI 96718
> "Democracy used to be a good thing, but now it has
> gotten into the wrong hands."   --Sen. Jesse Helms
>