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Re: First Uncinant / Human Evolution / 1st Theriz.



John V Jackson wrote:

<Can't think of anything much to say about the new Theriz, except it's
a bit too big to fly itself.  However, the wrist structure of
therizino..s is "obviously" ex-flying.>

  Don't know what you mean by this.

  All known therizinosaur/segnosaur wrists are more like those of
ornithomimids or prosauropods (albeit a little squashed
proximodistally), so tell us rather little, as both groups seem to be
good canidates for "closest to", as well as oviraptorosaurs.

<I am very worried by the idea of a backward pointing pubis evolving
pre-Archaeopteryx - which was exhibited in (certain?) late K
segnos/therizi...s.>

  Certain, yes. *Segnosaurus*, for instance, one specimen with pelvis,
foot, some vertebrae and ribs I believe, and the jaw.

<If V11579 had a backward-pointing pubis, this would mean . . .
b-p.p's evolved twice in flying forms - once for theriz's, and once
for uncinants.  And if V11579 flew, or had flying ancestors, it, they
and it's Jurassic descendents were very shy.  OR - maybe
segnos/theriz..s, about which we know so little, were polyphyletic in
some way . . . or maybe V11579 isn't a segnosaur ? ? ?>

  Next canidate is a prosauropod.

==
Jaime A. Headden

Qilong, the website, at:
http://members.tripod.com/~Qilong/qilong.html
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All comments and criticisms are welcome!

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