[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: Introducing: Sinovenator changii



Jaime Headden wrote-

> This leaves the appelation to
> personal opinion, nothing else. My statement was to regard the specimen
> not by personmal sentiment, but by a fullness of the data that can be
> divulged from it.
> There is no other valid use of the term, and only in Mickey's
> analysis lately does the specimen come out as next to *S. millenii*.

Makes it sound like other analyses have differing opinions, where in reality
no reference I've seen disputes the fact NGMC 91 is closest to
Sinornithosaurus.  I would agree that it should be labeled to reflect the
"fullness of data that can be divulged from it" and not personal opinion.
However, I would also argue the "fullest" analysis of the specimen currently
available is my post to the list
(http://www.cmnh.org/fun/dinosaur-archive/2001Apr/msg00683.html).  If anyone
else has new data that points to a closer relationship to another named
taxon besides Sinornithosaurus, feel free to present your opinion.  Note
that referral to Microraptor is even less probable now than when I wrote
that post, as Hwang et al. (2001) revealed this taxon has subequal
metacarpals and an enlarged first manual ungual, neither of which is seen in
NGMC 91.  In fact, Ji et al. (2001) had only this to say about the
phylogenetic relationships-
"NGMC 91 is similar to the dromaeosaurid Sinornithosaurus. They have similar
teeth. Both share several characters in common with dromaeosaurids, but they
and Microraptor display such uncharacteristic dromaeosaurid features as
non-ginglymoid distal articular surfaces of the metatarsals and
arctometatarsalian metatarsals. Some characters may prove diagnostic of this
taxon (for example, the unusual bowed metacarpal I), but we cannot determine
whether these are affected by ontogeny.  Because allometric scaling could
account for some of the differences between Sinornithosaurus and NGMC91,
measurements from these skeletons were compared and found to be highly
correlated (r < 0:983)."
Seems to be in accord with my opinion- Closest to Sinornithosaurus, either a
young individual of that taxon or a related taxon (I just don't like the
title they gave it and how short the published comparison was).  What other
published opinions are there?  Indeed, what other unpublished ones are
there?  Longrich (2001) put it next to Unenlagia, Rahonavis and
dromaeosaurids in his SVP analysis.  I didn't see Sinornithosaurus in his
cladogram.  Paul (2001) referred to it as Sinornithosaurus in his SVP
presentation.  Does anyone have an alternative hypothesis they'd like to
support?

> It has never been referred to as anything other than the specimen number
or
> Dromaeosauridae gen. et sp. indet. in any published analysis including it
> (doesn't matter if it's a cladistic analysis or not).

Does that mean we can't refer to it as something more accurate?  I would
hope we're not limited to referring to taxa only as they've been referred to
in published articles.  Lingyuanornis is clearly a junior synonym of
Liaoxiornis, but this has never been published.  We're free to refer to
Lingyuanornis as Liaoxiornis, I would hope we could call NGMC 91 cf.
Sinornithosaurus as well.

Mickey Mortimer