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Re: [Combined answer: Feathered/scaly theropods: trying to make the point.]



"David Marjanovic" <david.marjanovic@gmx.at> wrote:
> BTW, *Santanaraptor*, *Scipionyx* and AFAIK *Pelecanimimus* come from
> environments that didn't preserve the uppermost skin layer(s) with all its
> appendages. Therefore all skin from there appears naked.
> 
> Hair on pterosaurs from Solnhofen, including *Rhamphorhynchus*, IS
> occasionally preserved and has been known for 150 years or so; recent paper
> on *Pterodactylus* in Neues Jahrbuch. At least the Berlin specimen of
> *Archaeopteryx* did preserve some kind of contour/proto/...feathers, but
> most has been prepared away to reveal the bones. Remains can still be seen
> on e. g. the legs.
>         Why not more? Why isn't every pterosaur from there totally covered
> in fur? Because the limestone there preserves _impressions_ of soft parts,
> whereas Messel and Sihetun etc. preserve AFAIK carbonized remains of the
> stuff itself.
> 
> Considering "funky plants"... yes, this is indeed more probable than the
> protofeathers being witchcraft. All else I could say on this has been said.
> 
> Non-dinosaurs from Liáoníng have been known for 100 years or so -- just
> who's interested in fish and publishes on them in journals read by
> listmembers? :-> Several beautifully preserved insects from there are lying
in the museum here in Vienna. Wings, legs, antennae, but not the slightest
fuzz.

++++++++++++++++++++++++

Strange considering that a few of those would have likely been been somewhat
fuzzy. Incidentally where in Liaoning were they found? Anywhere near the
"fuzzy" dinosaurs?

___________________________
> 
> Fossils from China are usually published in Chinese geology magazines and
> suchlike. The new specimen of *Monjurosuchus*, however (the first one was
> found in the 30s during the Japanese occupation), was published in the
> relatively available Vertebrata PalAsiatica one or two years ago. I could
> find the ref in the university library. The photo in that paper is really
> beautiful -- a lizardlike normal-snouted champsosaur with patches of
scales.
> 
> Other bird finds from there? *Changchengornis*... *Liaoningornis*...
> *Songlingornis*... *Chaoyangia*... IIRC *Sinornis*... and the more recently
mentioned ones that may amount to 10 or so. All covered in whatever types of
feathers.

+++++++++++++++++++

Again, how close were any of these finds to, say, _Beipiaosaurus_ or
_Sinosauropteryx_?

Heck, how close was that _Psittacosaurus_ to these guys?

____________________
> 
> Just why did you write "all" dinosaurs were scaly when you knew well
that_some_ at least weren't? ~:-| I didn't even imply cladistics.
> *Protarchaeopteryx* and *Caudipteryx* with their remiges and rectrices are
already more than 0.

++++++++++++++++++++++++++++

Okay, this has apparently come up a lot and it's partly my fault. By stating
all dinosaurs are scaled until proven otherwise, I was parodying an American
law phrase which is "Innocent until proven guilty." That doesn't mean that all
proposed mass murderers and petty thieves are innocent regardless, it just
means that they are considered, by default, innocent; and that positive
evidence must be put forth to validate their guilt. 

Likewise with dinosaurs. Scale impressions from taxa as separate as
ceratopians and tyrannosaurs have been found, with many little scaly dino
impressions inbetween (including in embryonic sauropods). Furthermore we have
scale impression from (distantly) related reptiles dating at least as far back
as the Triassic (a certain rhynchosaur comes to mind) thus providing further
evidence for the plesiomorphy of scalation. As such, I consider all dinosaurs
to be scaly animals by default and that positive evidence is required to state
anything otherwise. _Caudipteryx_ is such evidence and I don't contest it's
featheredness. NGMC 91 might fall in there as well (I'd count
_Protarchaeopteryx robusta_ as well, but last I checked, it was considered
avian). The evidence for the other three is less conclusive for reasons I
mentioned in a previous post.


So to rephrase: "All dinosaurs should be considered scaly by default, unless
there is evidence to the contrary."

Jura

P.S. To Tim Williams - Appreciate the reference, even if the post did make it
sound like I came into this rather uninformed.

Oh and does anyone know the full ref for the Liaoning _Psittacosaurus_ paper?

 

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