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Re: SVP Preview

Speaking of coloration in fossils, I was once told of a Jurassic ammonite
that preserved its original coloration: blood red. I forget where it was
from, but I'm sure it wasn't a preservational artifact.

Student of Geology
400 E. McConnell Drive #11
Northern Arizona University
Flagstaff, Az. 86001
AIM: TarryAGoat

----- Original Message -----
From: <longrich@alumni.princeton.edu>
To: <dinosaur@usc.edu>
Sent: Thursday, September 26, 2002 9:58 PM
Subject: Re: SVP Preview

> On Wednesday, September 25, 2002, at 05:18 AM, Mickey Mortimer wrote:
> > Longrich presents his "NGMC 2124 is not Sinosauropteryx" hypothesis.
> > Instead it is more derived, related to Coelurus, Compsognathus and
> > Ornitholestes.  Sinosauropteryx is said to be more basal, close to
> > Allosaurus.  He suggests the presence of striping can be observed in the
> > integument.  Yangchuanosauria is defined as all closer to
> > Yangchuanosaurus
> > than Aves.  Looks like a junior synonym of Carnosauria to me, but who
> > knows
> > what support he has....
> It was Mick Ellison at the Mexico SVP who suggested to me that the
> stripes were a real feature of the animal (they are most definitely
> there although mainly on the NIGP half of the animal) just to give
> credit where it is due. This sounds remarkable but it isn't- Feduccia's
> book shows a Green River dragonfly with color patterns on the wings and
> I've seen striping in the tail of a Green River bird. I picked up some
> "devil's toenails" (Mancos Shale oysters of genus... hell, I'm a vert
> guy, I'm happy just to know its a mollusk) out in central Utah and
> washed them off in the sink and was rather surprised to note... stripes
> (this is a published phenomenon incidentally so I'm not just seeing
> stripes everywhere). Also someone showed me a book on Chinese invert
> fossils from Liaoning and they show all sorts of color patterns like
> stripes and spots in the insects. So it is very possible that the
> stripes are just that; lamentably the larger specimen has the distal
> tail broken off, but the proximal tail shows banding on the underside.
> That's too much coincidence for me personally. The big question is...
> why no dark feather traces on the underside of the body? Was it
> ventrally unfeathered or were the feathers light, i.e. countershaded?
> re: phylogenetics I haven't argued that NGMC is related to any of
> those guys except in the general grade, rather than clade, sense. I
> can't think of a single good synapomorphy that would unite any of them
> (with a couple possible characters maybe possibly uniting a
> Coelurus-Compsognathus group), but they all seem to fall roughly at the
> same level of the tree. We just don't know, but unfortunately the
> tendency to lump 2124 with Sinosauropteryx, and then this chimera
> Sinosauropteryx with Compsognathus, has put us farther from knowing
> exactly what was going on. I wouldn't be surprised if it was related to
> one of the three, I wouldn't be surprised if it wasn't, either.
> Yangchuanosaurs... not tons of evidence. I just wanted to emphasize the
> hypothesis that Yangchuanosaurus, Sinraptor et al. are more basal than
> Allosaurus. Though I may be jumping the gun a bit on this, I think a lot
> of the evidence for allosauroid monophyly is arguable. Its worth noting
> that a number of important characters conflict with allosauroid
> monophyly. Yangchuanosaurs apparently had a fully enclosed pubic
> obturator fenestra, a fourth metacarpal, a low, massive astragalar
> ascending process which is more reminiscent of _Torvosaurus_ than
> _Allosaurus_, and caudal hyposphene-hypantra articulations. I'd disagree
> with some of Tom's characters, e.g. there is a tyrannosaur dorsal I've
> seen illustrated (I think it was Makovicky's thesis) with an anteriorly
> inclined neural spine so I don't think that's an allosauroid
> synapomorphy. The large lateral exposure of the antorbital fossa might
> argue for allosauroid monophyly, although the pneumatopores included
> within may not (you can't have pneumatic invasion of the nasal without
> that antorbital fossa, so I figure the character is "inapplicable" to
> anything without it).
> I'll be upfront and say that I haven't had the chance to study
> skulls in depth so I really can't say too much there, but I think
> they're a bit overrated for higher-level systematics. Hips and ankles
> are where it's at, in that they tend to be highly conservative at the
> family level, from what I can tell although I just try to be honest and
> code everything I can confidently and objectively assign a 1 or 0 to. I
> don't believe that more characters is necessarily better, since by the
> time you get to the end of looking for characters, most of the good,
> easy, obvious ones are gone so to get that extra ten or fifty I'm often
> scraping the barrel for a bunch of subjective, highly variable stuff. I
> may actually end up with fewer characters this year than last. What I
> have done is look at bones. Lots and lots of them.