Is there a feathered juvenile *Psittacosaurus* specimen?

[David Marjanovic <david.marjanovic@gmx.at>]

No.

Today morning I received, for reasons I don't quite understand at the 
moment, a reprint of

Alan Feduccia, Theagarten Lingham-Soliar & J. Richard Hinchliffe: Do 
Feathered Dinosaaurs Exist? Testing the Hypothesis on Neontological and 
Paleontological Evidence, Journal of Morphology 266, 125 -- 166 (10 
October 2005)

Figures 11 through 14 show a small specimen attributed to 
*Psittacosaurus*. (From looking at the small inset in fig. 11, I can't 
tell if it might be *Hongshanosaurus* instead, but of course this wouldn't 
matter much. BTW, the specimen is totally flattened -- the right ilium is 
not broken, but disarticulated and horizontal to allow the "spread-eagle" 
pose.) It is called "the Nanjing specimen" and "*Psittacosaurus* from 
Nanjing". I'd bet money that it comes from Liaoning at the other end of 
China instead, and I also suspect that the geological institute of Nanjing 
has more than just one specimen; so providing a specimen number would have 
been really nice, especially considering the fact that the specimen is 
completely unpublished otherwise. But all this doesn't matter for the 
present topic.

That it is called an "ornithopod", while for decades it has been known to 
be a ceratopsian instead, also doesn't matter -- it doesn't change how far 
away it is from the origin of birds.

It also doesn't matter that fig. 11A claims that fig. 11C is a 
magnification of the belly (including the knee) while fig. 11B claims it's 
a magnification of the chest (including much of the shoulder area); 
judging from fig. 11C alone, it is neither.

While I am at it, I'll also mention that of the "ribs" identified in fig. 
12 only the longest is one (and continues through the "tissue mass"). The 
others are dead obviously not ribs. They form a star shape with the 
genuine rib, are extremely short and shapeless. They must be some 
diagenetic mineral precipitations -- smaller ones can be observed all over 
fig. 12A.

But enough waffling about the glaring failures of peer-review. In fig. 11C 
I see the striations that are called "integumental structures, very 
similar to 'protofeathers'" in the abstract. Neither scales nor "quills" 
are visible.

Firstly, the striations seem to have a rather random orientation. They are 
not bundled into branching structures. Many are parallel over some 2 cm.

Secondly, they are clearly not part of the skin or the connective tissue 
under the skin. They do not pass over the ribs. Instead, they continue  
UNDERNEATH the ribs, as can be seen in fig. 13A where a rib has broken 
away, probably with the counterslab. (In most other places, the ribs are 
still partially or entirely on the slab.)

So, the striations are not feathers (removing the possible contradiction 
with the published *Psittacosaurus* specimen with quills on its tail and 
scales over the rest of the body). But neither are they collagen fibers in 
or under the skin.

I don't have an idea what they could be. Collagen fibers from the lining 
of the body cavity??? (That would necessitate *Scipionyx*-like 
preservation in which no trace of the longest-lasting soft parts is 
preserved while the fast-decaying internal organs change the local 
chemical environment so much that all manner of minerals precipitate in 
their places. This is not expected from the Yixian and Jiufotang Fms.)

But in any case, the specimen is important because it shows that not all 
striations in the Yixian and/or Jiufotang Formations are feathers.

-------------------------------------------

But as we all know, Feduccia et al. go on to claim that none of them are 
feathers, except maybe those found on unquestioned birds. What about this 
claim?

Unfortunately I can't evaluate it. Figures 9 and 10, which show the 
holotype of *Sinornithosaurus millenii* (this time with specimen number), 
are descreened.

That's right, they have an abominably low resolution and have been 
descreened.

The many magnifications just have bigger descreened pixels than the base 
images (showing they are not separate photos, even though they should be).

As a result I cannot see anything. All the carefully inserted arrows point 
to nothing for me. The demarcation lines do not delimit anything I can 
recognize. It is as if I were wearing the wrong glasses. My eyes start 
hurting when I try to interpret anything into fig. 9 and 10.

Not that it matters, but privately I wonder who is responsible for this

                       _*MONSTROUS STUPIDITY*_

. (Or is it ignorance -- did someone just merrily click around in 
Photoshop and didn't find the admittedly confusing "go back" in the menu?) 
It must have been committed before the images were submitted for 
publication, because the arrows, lines, scale bars and text ("A", "B", "c" 
[sic], "1", "2", "3" and "5 mm") are not descreened -- although the 
letters in fig. 9 are underlain by descreened white patches. The circles 
around the magnifications, however, are descreened, so much that they 
almost look like hand-painted. Again the peer-reviewers cannot escape 
without blame -- it was their job to notice the _informationless_ figures.

I emphasize that the other figures in this paper are _not_ descreened, 
except for fig. 14 (where the facts that it wants to show, the collagen-
like multiple orientation and the beaded appearance of some striations, 
are still visible), and _maybe_ for fig. 5C and 15D (but only very 
slightly) which may just have too low resolution.

-------------------------------------------------

On to the last new claim about a fossil. Illustrating an apparently 
unpublished specimen of *Pelecanimimus*, Feduccia et al. claim there are 
scutes on its forearm. Well, could be. I can't offer an alternative 
interpretation, even if only because the resolution of fig. 15B and C is 
so small. It is true, in any case, that feathers do not appear to be 
preserved in that place (at the very least).

Why all this doesn't matter for the idea that *Pelecanimimus* had 
(apparently, as usual, unpreserved) feathers on the rest of its body 
(except most probably the feet) has already been explained.

As has likewise already been mentioned, *Pelecanimimus* is, although an 
ornithomimosaur, not an ornithomimid, yet Feduccia et al. label it as 
such, and the skeletal reconstruction shows *Ornithomimus* or 
*Struthiomimus* (two actual ornithomimids) rather than *Pelecanimimus*, as 
is already obvious from the fact that Carroll (1988) can't have known 
about a fossil described in 1994, yet Feduccia et al. call it "Skeletal 
reconstruction of *Pelecanimimus*". One more in the list of gigantic, big 
and small peer-review failures in the publication of this article.

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