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Re: Moroccan noasaurid?



Jaime Headden wrote-

>   I did in fact describe in my paragraph which ones do not have the
> sagittal crest. One is *Indosuchus*, without even a medial crest caudal to
> the triangular plateau, and the other is *Abelisaurus*. Carnotaurines, as
> I said, always have one. *Avimimus* has a small crest on the top of the
> inter parietal plateaus, but this is between the supratemporal fossa. This
> would make such a crest non-analogous to those of other maniraptorans. The
> same is true for some advanced oviraptorids. As I described, only some
> _basal_ oviraptorids have the crest, but I should elaborate that this is
> the _true_ crest for the mandibular adductors.

Your wording was quite difficult to follow in that case-
"... as well, only some abelisaurids have the crest and these are generally
carnotaurine (specifically, *Aucasaurus,* *Majungasaurus,* *Carnotaurus,*
and *Indosaurus*), or are tapered from the interparietal plateau caudally
(as in "abelisaurines" like *Abelisaurus* and *Indosuchus*."
looks to me like "only some abelisaurids have sagittal crests and these (the
ones with the crest) are generally carnotaurine or tapered caudally".  Oh
well.
The real issue is that both Carnotaurus and Abelisaurus have almost
identical crests, tapering posteriorly.  Carnotaurus actually has a wider
crest than Abelisaurus.  Indosuchus definitely has a sagittal crest, as its
supratemporal fossae are actually confluent.  That's one reason it was
thought to be tyrannosaurid by Chatterjee (1978).  Your statement regarding
Avimimus' crest is confusing as nearly all theropods with a sagittal crest
(Tyrannosaurus, Troodon, etc.) have it between the supratemporal fossae.
Where else would it be?  That's what creates the sagittal crest in the first
place, the supratemporal fossae converging medially.  Some oviraptorids may
have a different condition, where the sagittal crest is on the broad
platform between the supratemporal fossae, but this is the exception.

>   *sigh* ... I didn't say it was a maniraptoran ... or a maniraptoriform.
> I only provided an alternate hypothesis and interpretation. I have no
> intention of proving you wrong.

You should word your sentences differently then-
"The animal was probably maniraptoriform, and the lateral and dorsal
orientation of the lateral wings of the frontals suggest it was
maniraptoran."
.... sounds to me (and most people I assume) to mean you think the taxon was
probably maniraptoriform, and perhaps a maniraptoran.  Which is a different
opinion than mine (probably abelisaurian, possibly noasaurid).
If you have no intention of proving me wrong, why- 1. debate the validity of
my evidence (sagittal crest); 2. provide an alternative hypothesis
(maniraptoriform); 3. support your hypothesis with data (binocular vision,
large orbit, pneumatic); and 4. present that hypothesis as more probable
than mine (The animal was probably maniraptoriform...)?
Both of us cannot be right, so presenting your hypothesis as more probable
is an attempt to prove me wrong.  Not that I mind, I like defending my ideas
(as scientists do).
Now, do you believe it is maniraptoriform still, and do you have
counter-arguments to my reasons your maniraptoriform characters are invalid,
and why the cerebral hemispheres are so small?

Mickey Mortimer