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What Wiens 2003 has to say



Wiens notes that "even the relationships of highly incomplete taxa (e.g.
95% missing data) can be accurately reconstructed.... Adding incomplete
characters can improve accuracy under many conditions, but inadequate
taxon sampling in these characters can lead to problems..."

I concur.

Because fossils are so rare and often incomplete we're going to have
problems in character and taxon sampling from the start. We're all
hobbled, so to speak.

Futhermore, I think we all agree upon "more is better." So if the first
study has a dozen taxa. The second should have more to be better, right?

A good cladogram, one that is 'one' with Nature, should be able to hold
up with the addition of taxa and characters. Prior work (some 39
cladograms of various slices of the Diapsida) have at most 54 taxa
(Evans 1988). The next highest taxon number is 33 and it falls quickly
into the 20s and teens for most work. This should be far too few in
anyone's estimation. Yet these are the studies upheld as 1. generally
agreed upon (yet none match one another) 2. true (yet incerta sedis and
lack of resolution hound them) or 3. traditional (only because later
workers did not test them by tacking on more taxa).

Funny then, the slings and arrows I'm getting after doubling and
quadrupeling these numbers. Funny also that, as scientists, no one on
the DML has been curious enough to ask to see the data, the results, or
the figures.

You know I would have.  ;   )

David Peters
St. Louis

PS. I realize that larger and gigantic studies are being made of
Dinosauria, Aves and Crocodylomorpha, but these are, in the scheme of
this discussion, small dusty corners of a larger house that we're trying
to understand the basement and blueprints for.