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Re: Recoded Aves eliminates polyphyly
Ken Kinman (email@example.com) wrote:
<And according to a post by Mickey, Caudipteryx does have a convex
coracoid glenoid (so it satisfies the first criterion according to him).
And it's "semilunate" is enlarged and fused (and I noted that it and
Protarcheopteryx have modified the distinctive shape somewhat). That is
why I put semilunate in quotation marks. So I don't see how Caudipteryx
fails this definition on either criterion.>
Because it does not possess a semilunate in the same extent and form of
that in dromaeosaurids or oviraptorids. The carpus of other
oviraptorosaurs is unknown, so reducing the ability to diagnose
variability. They may develop into a parallel condition. You may also
recall that Mickey expressed that there was a possibility of *Caudipteryx*
having a bipartine semilunate where the first and second carpals were
unfused. This was the opinion forwarded by Ji et al. (1998), Zhou and Wang
(2001) and Zhou et al. (2001). Though it may or may not be possible, there
is doubt expressed to this. I coded *Caudipteryx* as having the derived
condition in both fusion and appresion, but the extent of the carpals and
form of the semilunate profile are decidedly plesiomorphic in being low
and "oblate" in profile. Recoding *Caudipteryx* pulls it into a polytomy
with all other dinosaurs except *Iguanodon*, which is even more primitive
but also possesses a fully fused carpal block, partial carpometacarpus
(metacarpal I is fused to distal carpal 1, which is fused to distal carpal
2), and fully appressed carpal block to proximal metacarpal surface and
extent of the carpals to the same. This leads a functional consideration
to the entire complex except the more or less 180[degree] profile of the
semilunate, which in accordance to *Caudipteryx*, may be secondarily
derived in oviraptorids and paravians. Unfortunately, this seems to have
been "solved" by making *Caudipteryx* a non-oviraptorosaur, against tons
of ignored data.
Curious, but have you ever checked the literature yourself? Or the
material? I have created a completely independant research of the
literature and personal photographs and worked from there ... but I would
like to also know why you so easily take a person's word over another
without having first looked at the material for yourself?
But who am I to argue against the Kinman System....
Jaime A. Headden
Little steps are often the hardest to take. We are too used to making leaps
in the face of adversity, that a simple skip is so hard to do. We should all
learn to walk soft, walk small, see the world around us rather than zoom by it.
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