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RE: Deep Scaly Project
I can't tell you how much I agree with your thoughts here, Tom.
Re: the number of characters, I was wondering if you, or anyone else, had any
thoughts concerning Chippendale and Wiens 1994 (Systematic Biology 432:
278-287) theoretical work that seemed to indicate that only 150 or so
characters were needed to bring the probability of estimating correct phylogeny
to the 95th percentile (rapidly evolving characters), while 300 skirts the 99th.
From: "Thomas R. Holtz, Jr." <firstname.lastname@example.org>
Sent: May 16, 2005 1:03 PM
To: david peters <email@example.com>, firstname.lastname@example.org
Subject: RE: Deep Scaly Project
> From: email@example.com [mailto:firstname.lastname@example.org]On Behalf Of
> david peters
> The Field Museum is part of a project to figure out the family tree of the
> I was wondering, to date who has authored the most comprehensive account of
> clade? And why does it have to be improved or further resolved?
Note that this is for Squamata only, and by no means all of Diapsida!!
And why does it have to be improved? Because there remains major contraversies
within it (esp., but not exclusively, the position of
snakes), and because previous work tends to be less global and thus more likely
to miss important potential groupings (i.e.,
snake-only papers, or ones with just one examplar for each "family", or the
like). Indeed, looking at their taxon sampling, it might
be nicer to see a lot more. After all, there are more living squmate species as
there are living mammal species!!
Furthermore, this project will combine molecular and morphological data.
To do all of Diapsida to some reasonable scale would require many times the
number of characters and taxa here. Even to do a "all
major types of fossil diapsids, minus the modern-type lepidosaurs and
modern-type archosaurs" would be quite an task: literally
dozens to a few hundred of taxa and many hundreds of characters.
Thomas R. Holtz, Jr.
Department of Geology Director, Earth, Life & Time Program
University of Maryland College Park Scholars
Building 237, Room 1117
College Park, MD 20742
Phone: 301-405-4084 Email: email@example.com
Fax (Geol): 301-314-9661 Fax (CPS-ELT): 301-405-0796