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Re: Prolacertiformes and Protorosauria
David Peters wrote:
Once again, if sister taxa don't bear a family resemblance, you have
to doubt the results.
Wait - I'm confused: don't the sister taxa bear "family resemblance"
*by definition*? The tree constructs the best estimate of ancestry,
using some kind of estimate of family resemblance. For morphological
character sets, this usually means using a parsimony algorithm, with
is optimizing the distribution of characters and using synapomorphies
to define clades. Since you're joining taxa using shared derived
character states, they *must* bear resemblance. The fact that those
taxa may have some kind of qualitative or intuitive lack of
"resemblance" doesn't mean you screwed up.
I added breaks at nodes that did either had closer excluded sisters
or just plain did not make sense. Without an overall understanding
of amniote relations, studies such as this one, undertaking such a
huge gamut with too few real sisters will bear little real results.
How do you determine which groupings make sense - isn't that the point
of constructing the tree in the first place? What's a "real sister"?
Michael Habib, M.S.
Center for Functional Anatomy and Evolution
Johns Hopkins School of Medicine
1830 E. Monument Street
Baltimore, MD 21205