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Re: Dromomeron and Lagerpeton query
----- Original Message -----
From: "David Peters" <firstname.lastname@example.org>
Sent: Tuesday, July 14, 2009 9:36 PM
Seeking an opinion here.
Since Dromomeron and Lagerpeton are known principally from hind limb
materials, its not surprising that the recent matrices of Nesbitt et al.
2009 (JVP) based on Irmis et al. 2007 (Sciene) had a larger than typical
number of characters devoted to the hind limb.
Is that a bad thing? I'm thinking of Bennett's rejection of hind limb
characters in a similar matrix in 1996.
I haven't read that paper. Can you find any that are correlated?
BTW, if you add Tropidosuchus, Chanaresuchus, Cosesaurus and
Huehuecuetzpalli to the Irmis et al. matrix, these all end up as
Ornithodires. What can we do to fix this?
Did you keep *Euparkeria* as the outgroup? Because that's what the outgroup
is in the Nesbitt et al. paper (Irmis is the 2nd author). If you run an
analysis where *Allosaurus* and *Huehuecuetzpalli* are part of the ingroup
and *Euparkeria* is the outgroup, you have to _expect_ getting random
garbage as a result. Especially if there are no characters in the matrix
that are informative for large-scale diapsid phylogeny.
Remember: if you don't explicitly specify an outgroup, PAUP* uses the first
(topmost) OTU as the outgroup.
In this case, you'd either have to use *Huehuecuetzpalli* as the outgroup or
add a non-crown-diapsid outgroup to the matrix.