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

Re: MORE "Dinosaur Planet"dinosaurs!!!(This time with feathers)

This is my reply to Timothy's originally (and accidentally) offlist reply to
my.... reply to his original message.

You (Timothy Bridgeman) wrote-

> I have no problem with anyone arguing against any of my viewpoints.If you
> can prove me wrong,then by all means do so.What's the worst that can
> happen?I'll have a better understanding of the animals in question?
> So in your own words,"LET THE FIRING BEGIN!"

That's a good philosophy.  But why not on the DML?  Fine with me of course.

> I was not referring to every specimen of Microraptor ever found,I meant
> best evidence in favor of feathered dinosaurs,specimens like"Dave"which
> come from the same source as "Archaeoraptor".The reason I have no doubts
> to validity of Caudipteryx was because that had not come from the same
> source.However,some of the patches of preserved integument on the
> of Microraptor could possibly have been from birds and gotten preserved
> the same matrix.

There are now eleven specimens of Microraptor/Cryptovolans described in the
literature (Xu et al., 2000; Czerkas et al., 2002; Hwang et al., 2002; Xu et
al., 2003).  At least six of these have undeniable feathers.  Three are from
Shangheshou, three are from Dapingfang.  NGMC 91 (Dave) is from Fanzhangzi.
So the best evidence of feathered dromaeosaurs does not come from the same
quarry or even the same city as NGMC 91, and where exactly the
"Archaeoraptor" specimen is from is unknown (no precise locality data were
taken by the collector before it was forged and sold).
Do you really think that it's likely the feathers of Microraptor gui's
holotype are bird feathers that happened to be placed in exactly the right
place to have perfect wings with primaries, secondaries and coverts, similar
arrangements on the legs, and retrices on the distal tail?  It even has
little pennaceous feathers on its head.  There are no other bones in the
matrix, no extra birds (note the X-ray CAT scan).  And some of this specimen
was prepared at the IVPP, so the feathers weren't faked.  And the other
specimens just happen to have a similar arrangement of feathers, some better
preserved than others (the retrices of TNP 00996 are particularily
complete).  The holotype was even CAT scanned to ensure all the slabs belong
together.  What possible evidence could you have for these being
non-Microraptor feathers?

> The plumage seen on the recent specimen of Microraptor,(M.gui,the "four
> winged"dinosaur)was not part of the original fossil.The plumage seen on it
> now is said to be based on the holotype and referred specimen,which was
> top half of the "Archaeoraptor"specimen,the birdYanornis(not
> Microraptor).Therefore,while it may be"INCREDIBLY difficult to fake the
> feathers",it certainly is not impossible.

You're misunderstanding something, though your wording makes it difficult to
tell just what it is.
The feathers on Microraptor gui's holotype (IVPP V13352) the four-winged
dinosaur as you call it) ARE part of the original fossil.  In fact, the
feathers are preserved on the same slabs as the bones, and some were even
under matrix when prepared, as noted above.  It's feathers have nothing to
do with the Yanornis top half of "Archaeoraptor" (IVPP V12444), or the
Microraptor tail of "Archaeoraptor".  I think the tail section of
"Archaeoraptor" was the counterslab of the holotype of Microraptor
zhaoianus' tail (IVPP V12330), but am unsure.  The same could be said of the
referred specimen of M. gui (IVPP V13320).  M. gui's feathers are not based
on the "Archaeoraptor" specimen in any way.
I see nothing in your paragraph showing where feathers were faked, and
continue to believe making feathers under sediment is beyond our current
technology, as is constructing such elaborate sets of feathers on both slab
and counter slab.  These are actual feather remains, remember, not

> They show more avian features than those of dinosaurs to me.Caudipteryx
> example is closer to Archaeopteryx than to the oviraptorsauria,to which it
> seems to have been classified.
> (I've noticed that no two paleontologist's view of how the dinosaurs are
> related one another is the same.There are always variations.In that
> are not likely to convince each other here.)

There are always variations, but trying to argue Caudipteryx isn't a
dinosaur is like trying to argue a dog isn't a mammal.  Let me put it
simply, the supposed bird-like characters noted by Feduccia et al. are
1. Also found in oviraptorosaurs (teeth with constricted roots and no
serrations; no maxillary or dentary teeth; external mandibular fenestra
present; enlarged premaxilla and reduced maxilla; ball-shaped femoral head).
2. Unknown (but unlikely) in Caudipteryx (ventrally directed foramen
3. Circular reasoning (pennaceous feathers).
4. Not present in Caudipteryx (pygostyle; four carpals; no pubic boot;
hypopubic cup; reduced fibula; reduced calcaneum; reversed hallux).
.... except for the shortened tail, which is actually shorter than other
oviraptorosaurs and Archaeopteryx, so is like advanced birds.  Also, there
are fewer dorsal vertebrae (and thus more cervical vertebrae) and a reduced
third manual digit, that are both like very advanced birds (more advanced
than Confuciusornis).  But Caudipteryx lacks a ton of features these kinds
of birds have (heterocoelous cervicals, pygostyle, strut-like coracoid,
carpometacarpus, trochanteric crest, tibiotarsus, tarsometatarsus, reversed
hallux, etc.), so is certainly not part of that group.  I would really like
to see your list of characters in which Caudipteryx is more like birds than
Here are some reasons Caudipteryx is more primitive than Archaeopteryx-
1. dorsal process of jugal placed too far anteriorly
2. more than nine caudals with transverse processes.
3. distal caudal vertebrae with prezygopophyses over 40% of central length.
4. more than twelve caudal vertebrae with prominent neural spines.
5. more than eleven dorsoventrally elongate chevrons.
6. short coracoid (maximum coracoid height <150% of length from anterior tip
to posterior edge of glenoid).
* This is also seen in the avian Sapeornis.
7. unfused sternal plates.
* This is also seen in the avian Shenzhouraptor (=Jeholornis).
8. metacarpal III not laterally bowed.
* This is also seen in several birds-  Sapeornis, Omnivoropteryx,
Patagopteryx, and Yixianornis.
9. metacarpal I > 32% of metacarpal II's length.
* This is also seen in confuciusornithids.
10. supratrochanteric process of ilium absent.
* This is also seen in Sapeornis.
11. prominent ventral extension of preacetabular process.
12. postacetabular process squared off.
13. pubic boot projects anteriorly.
14. no proximodorsal ischial process.
15. obturator process placed more proximally.
16. no capital ligament fossa on femoral head.
17. pedal phalanx II-1 <90% of phalanx III-1's length.
18. pedal phalanx II-2 <85% of phalanx II-1's length.

>  I personally find the objections to the use of an animal with such an
> enormous amount of connective tissue for their study irrelevent,because it
> still shows the extreme similarity of decayed connective tissue to what
> been referred to as"protofeathers".

The point is that having so much tissue above the braincase or tail of
Sinosauropteryx, or on the snout, arms and distal tail of NGMC 91, is just
ludicrous.  The animals used for comparisons by Ruben and Lingham-Soliar are
either aquatic with a thick layer of insulation (dolphins, ichthyosaurs) or
have fins (sea snakes).  There just isn't that much collagen in the various
body parts of terrestrial reptiles.  Even the birds-aren't-dinosaurs camp
was forced to admit Yixian coelurosaurs were insulated (though they still
refused a feather identity, they alled it hair) at the 5th SAPE symposium.

> > A couple questions....
> > 1. Why do other Yixian vertebrates not show collagen remains?  Not
> > Psittacosaurus, or Hyphalosaurus, or the turtles, or mammals....
> For the same reason that not all Sinosauropteryx prima specimens show
> collagen remains(or "protofeathers",whichever floats your boat).Some
> specimens fossilise better than others.

There are two described specimens, both of which show feathers.  The often
cited third specimen is actually a different taxon ("Huaxiasaurus"?), but
also has feathers.  A fourth specimen is known, but not described yet, and
not illustrated well enough to tell if feathers are preserved.
My actual point was that the non-dinosaurian taxa all preserve the "right"
type of integument if any is preserved.  The reptiles are scaled, the
pterosaurs and mammals furred, the birds feathered.  But none of these has
"collagen" preserved.

> > 2. Why are the collagen remains of coelurosaurs nearly identical to
> > preserved Yixian bird and dromaeosaur feathers?  What's the reason to
> > believe they are collagen?
>   For the same reason that the decayed connective tissues of the buried
> dolphin are nearly identical to preserved Yixian bird and dromaeosaur
> feathers.The similarities mentioned above is my reason to suspect the
> possibility that the preserved Yixian dromeaosaurs especially,show
> traces.(I include "Dave"in this,as you are right about it not being
> do not see a single identifiable feather in this specimen,only fibrous
> around the body and under the arms and fibers around the head and neck.)

But the decayed conective tissues of the dolphin are not like coelurosaur
In Sinosauropteryx, for instance, they come in two distinct thicknesses (.2
mm; <.1 mm).  In the dolphin, collagen fiber bundles were .03-.04 mm wide,
much smaller.
These two types of filaments also have different distributions (thicker ones
only located close to body) and orientations (thicker ones at a higher angle
to the body wall).  This suggests an organization like downy feathers, but
no mechanism for this arrangement has been put forth by collagen advocates.
In Sinosauropteryx, the feathers are the expected distance away from the
skeleton- close to the skull, hips and distal tail; far from the shoulders
and proximal tail.  This is contra the expected distribution of an internal
Also, Sinosauropteryx actually shows a regular striped pattern on its
feathered body (easily viewable in ultraviolet if I recall), with the
stripes missing ventrally (Longrich, 2002).  This has an obvious reason if
they are counter-shaded striped integument, but not if they are internal
Finally, the fibers of Shuvuuia (an alvarezsaurid theropod, which Martin et
al. don't believe is a bird) are made of keratin, as proven by chemical

Basically, your viewpoint is so highly flawed that not even its supporters
can hold on to it.  Feduccia (2002) now admits Cryptovolans was feathered,
and he, Czerkas (Czerkas et al., 2002) and Martin (pers. comm. at SVP 2002)
find it probable all maniraptorans were feathered.  Of course, they now
think all maniraptorans are birds, not dinosaurs.  No reasons to exclude
them from Dinosauria have been given, and I expect none to ever appear.
Feduccia has made it seem like feathered dromaeosaurs are a huge surprise to
everyone, which will make everyone rethink their ideas, but this isn't true
at all.  It fits just fine with the last two decades of theories from the
dinosaurs-are-birds camp.  Indeed, Feduccia and his colleagues are either
incredibly ignorant, or are horrendous liers.  I recommend reading the
attached paper (Prum, 2003 attached to original copy), which really gives a
good impression of the state of this

Mickey Mortimer