Mickey's experiment (segnosaurs)

["Ken Kinman" <kinman@hotmail.com>]

Dear All,
     I wrote the first part of this e-mail earlier, saved it, and stored it
until I found Mickey's posting on his experiment just now.
     Thus the first part of this post reflects my pre-experiment
impressions, and the second part will reflect my reaction after reading
Mickey's latest post.  Things seem to be shook up a little bit with some
surprises, but not as much as I thought they would be.
So it goes.
******************************************************
Mickey,
     Thanks for that preliminary "book review" or more accurately "thesis
review".  I will withhold judgment on some of the other aspects or Rauhut's
topology until the "experiment" is done, but will comment on one (which you
already commented upon):
     The idea of a Deltadromeus-Ornithomime clade does not "feel" right to
me at all (ooooppps, there's that "unscientific" intuition rearing its ugly
head again).  This is the one part of Rauhut's topology that jumped out at
me, and I agree with Mickey that Deltadromeus is too primitive to be a
sister group to ornithomimes.  If Deltadromeus is a coelurosaur at all, it
is a very basal form, more basal than even Tyrannosaurids, much less
Ornithomimids.
     I have a feeling Mickey's experiment will show this.  What is more
exciting is the unexpected results that it might generate.  Mickey seems to
have a real knack for teasing interesting possibilities out of all those
characters (so many characters, that frankly it sometimes makes my head
swim).   Maybe Sereno should be a little worried.  Especially since Mickey
is just getting started and I for one already trust his intuition a lot more
than Sereno's (particularly when it comes to cladistic analysis).  Intuition
certainly isn't the deciding factor, but my experience is that those who
have a more intuitive feel for characters have an easier time detecting
convergences (and other homoplasies) than those whose intuition is not as
well developed.
                  --------Ken
******************************************************    Mickey,
    I am, of course, disappointed that Therizinosauria are not polyphyletic
in your experiment, as I really expected them to be so.  I'll accept that.
That they are coelurosaurs seems to be strongly supported by your analysis.
However, I still think they may be slightly paraphyletic, with the majority
of Therizinosauroids (Alxasaurus, Therizinosaurus, and segnosaurids)
splitting off as a separate clade just before Beipiaosaurus, which would be
a plesion by itself or maybe even a basal oviraptorosaur sensu lato).  Will
have to think more about that more tomorrow when my brain is not so tired (I
am not much of a night person).
     However, what REALLY struck me was the Deltadromeus-tyrannosaur clade
that emerged.  Holy Smokes, I wasn't expecting that at all!!!!   My initial
reaction to this is that tyrannosaurs may have split off earlier in the
coelurosaur radiation than generally believed.  So much so that I can even
contemplate a Deltadromeus-tyrannosaur clade as sister group to the rest of
the coelurosaurs.  In other words, this clade could be intermediate between
carnosaurs and coelurosaurs (or split off as two separate clades between
carnosaurs and coelurosaurs).  Where Proceratosaurus might end up branching
off is even more uncertain (perhaps even between Deltadromeus and
tyrannosaurs????).  Too bad we don't have more material available for that
genus.
      Will have to ponder all of this tomorrow after a good night's rest.
It does very firmly solidify my doubts about a Deltadromeus-Ornithomime
clade (which was found in Rauhut's analysis), but it opens upon a lot of
doubts about the interrelationships of the basal coelurosaurs.
      But finally back to therizinosaurs again, I think it might be rather
interesting to see what your tree topology would look like if Beipiaosaurus
were completely omitted from the analysis.  In that case, would the
Alxasaurus-Therizinosaurus-segnosaur clade still emerge and fall out closest
to oviraptorosaurs?  At least that is the one further test that I think
might show something interesting.
      That's about the best I can do tonight.  Been a long day, and I
really need to recharge my batteries.  Thanks for the analysis Mickey----in
a strange sort of way I am a little relieved therizinosauroids are not
polyphyletic (but that Beipiaosaurus might make therinosaurians paraphyletic
is still a possibility in my mind).   Will ponder this more tomorrow.
            ---Cheers,   Ken Kinman
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