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



----- Original Message ----- 
From: "Mickey Mortimer" <Mickey_Mortimer111@msn.com>
To: "TIMOTHY BRIDGEMAN" <timlee3005@earthlink.net>
Sent: Wednesday, November 26, 2003 5:14 AM
Subject: Re: MORE "Dinosaur Planet"dinosaurs!!!(This time with feathers)


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

I was under the impression that "Dave" specimen was one of the best evidence
in favor of feathered dinosaurs,since it could be the most undeniably
classified as a dinosaur,unlike the much more birdlike Caudipteryx or even
Microraptor.

>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
> the
> > 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.

I refer you to www.dinodata.net to the listing for the genus Microraptor.In
the section on M.gui,it states:
"The integumentation of M.gui is based on the holotype and referred
specimen...." Unless I have misinterpreted something,it should say "The
integumentation of M.gui displays two types plumulaceous and pennaceous
feathers with a length of...." without saying that it is based on the
holotype and referred specimen.Using that term implies that it was not part
of the original fossil,but reconstructed based on other,similar specimens.

>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
> impressions.

I did not imply that ALL feather traces were fake,I was referring to the
possibility of fakery(one should not just pretend that the
"Archaeoraptor"debacle never happenned.)

> > They show more avian features than those of dinosaurs to me.Caudipteryx
> for
> > 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
> light,we
> > 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
> either-
> 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
> magnum).
> 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
> oviraptorosaurs.

Strangely enough,you have already listed for bird features than dinosaur for
Caudipteryx.
In common with oviraptorsaurs you list five characters in common.Then you
list overall around ten features in common with various groups of birds.(I
agree that Caudipteryx does not belong to the same group of advanced birds
as Confuciusornis.)

> 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.

Again,I would have to agree.

> >  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
> has
> > 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
> collagen
> > traces.(I include "Dave"in this,as you are right about it not being
> faked,I
> > do not see a single identifiable feather in this specimen,only fibrous
> tufts
> > 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
> feathers.
> 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
> fiber.
> 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
> fibers.
> 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
> analysis.
>
> 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, which really gives a good impression of the state of this
> "debate".

I would'nt say that my viewpoint is highly flawed,as it is all a matter of
interpretation of the evidence.That more people than not agree with the idea
that not only are birds descended from dinosaursARE birds,is of little
importance to me.While you could be right about it,I still can see other
possibilities.

> Mickey Mortimer
>