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Greg Paul's biplanes & Qilongia's inert mental butterflies



BRIEF COMMENT. This thorough explication of the
fallacies in Headden's iterations is long overdue, was
eagerly awaited. When considering the profound
ramifications of flight-as-survival among
end-Cretaceous theropods, even flightlessness among
some feathered theropods (parental care etc. still
intact), it is to Greg Paul's advantage that he has
had access to specimens and/or detailed scaled
photographs of specimens from China. This is, needless
to say, somewhat different from Headden's reliance
upon photocopies and rulers and vacuous
interpolations. The reason why I use Gregory Paul in
my book-in-progress, additionally, is because I can
trust he has "done the homework", organized the data
without presuppositions.
   Allow me to outline an example. In Dinosaurs of the
Air, Greg Paul has thought experiments re:
end-Cretaceous extinction processes. Much speculation,
over the years, has been given to droughts, global
fires, volcanoes, sea level shifts, etc. I remember
Ned Colbert telling me that he thought disease could
have played a role.
    Viruses to survive must not kill their hosts. If
dinosaur populations at the end-Cretaceous did
violently perish from a virus (land bridges between
previously isolated populations coming into existence,
as it were), the virus was not yet adapted to its
host, thus indicating species-to-species cross overs.
A DNA virus among dinosaurs would facilitate
generational transmission by remaining in the body,
not killing the dinosaur. But an RNA virus -- its
variability is derived from errors of replication --
is quite mutable and dxterous in avoiding immune
systems.
    Most viruses are eventually attenuated, the time
span involved is ca. 1000 years, and it could well be
some dinosaur incipient species were annihilated,
others surviving viral plagues. Of course, it could
well be some of the known, mounted, relatively
complete skeletons are of individuals who either died
of accidental causes (e.g., drowning), or were victims
of violent death from disease. Congenital
immunodeficiencies among extant avian dinosaurs have
yet to be fully described in the literature, but in
the late 1990s numerous theropod viral deaths were
documented from the West Nile virus. One wonders if,
during the Mesozoic, some dinosaur populations could
have experienced multifocal leukoencephalopathy,
killing gene pools. Unfortunately, no amber preserved
dinosaur tissues of age-classes are known containing
both envelope and core proteins of a virus to
determine if viral deaths were known in large breeding
dinosaur populations.
    All of these thoughts arose from reading Greg
Paul's thought experiments, and then familiarizing
oneself with the relevant literature. I know I am
stretching my extrapolation here, but thought
experiments, as suggested by Greg Paul, if predicated
upon rigorous, documented data, are more viable than
the screeds of those who, lacking imagination, rely
upon typewriters (or computer keyboard substitutes)
and tongue musculature extensions.
Thank you, GSP1954, for a delightful journey.
*******************************************************

--- GSP1954@aol.com wrote:
> Geeez, people are not even getting basic terminology
> right in this 
> discussion. 
> 
> Flight, Websters - passing through the air by the
> use of wings - I suppose 
> this covers helicopter blades and wingless flying
> bodies. A sailplane and a 
> nonflapping albatross fly just as much as an F-16 on
> afterburner or a pigeon 
> taking off. Flying squirrels fly as much as a hang
> glider. There are 
> different kinds of flight, some internally powered
> such as Spitfires and 
> racing pigeons, others externally powered (gravity
> and sometimes rising air) 
> such as condors, sailplanes and flying snakes.
> Whether flapping flight is 
> "truer" than wave soaring is open to question, in
> any case it is necessary to 
> be specific when addressing the issues of different
> kinds of flight.
> 
> Headden wrote:
> 
>   I did not measure *C. volans* [that's C. pauli],
> given that the slab is 
> underlit  in the
> Czerckas publication [the phoots are excellent]and
> it is not apparently 
> possible, as least with the
> scans I have, to see integument in much light. The
> photo of the LPM type
> in Norell et al. does not show how these are
> perfectly and fully
> preserved, and I do not trust Czerckas' allusion of
> lengths given tyhe
> conflation of the leg feathers to arm feathers. If
> anyone has better
> pictures of these regions, I would love to see them.
> However, my
> measurements for *M. gui* and *Archaeopteryx* stand,
> as they were made
> from the scales figured in their respective papers
> and, of all things,
> Greg Paul's _Dinosaurs of the Air_. The longest
> preserved feather of *M.
> gui* is shorter than the arml measured from glenoid
> to the tip of the
> second finger's claw.
> 
> Reply: I never claimed the primaries were longer
> than the arms. In most 
> flying birds the primaries are shorter than the
> arms, confusciusornids being 
> an interesting exception. What is true is that the
> primaries are longer 
> relative to the hands than they are in
> Archaeopteryx, and are closer to the 
> modern flyiing bird condition in this regard. 
> 
> <The most proximal preserved ulna feathers are also
> long, about as long as
> the ulna, maybe  longer - it being difficult to be
> exact from the photos,
> and there are badly placed sediment breaks in both
> specimens.>
> 
>   In *M. gui*, the secondaries wrap around the ulna
> on the right side, and
> it is not likely there was a vacent space inboard of
> the elbow.
> 
> R: Not sure what H means here. 
> 
> <When the wing is posed in a normal flight position
> it has a moderate,
> fairly typical forest bird chord/span ratio,>
> 
>   Considering I measured the chord and span from the
> given figure, and now
> again from the photo, I get a anspect ratio of
> around 5.25, lower than in
> forest birds.
> 
> R: How H can calculate such a ratio via photos and
> when the specimens are 
> damaged in these areas is a mystery. 
> 
> <The wings were therefore fully capable of
> generating as much lift as
> modern bird wings, and had high thrust potential as
> well.>
> 
>   This statement must be based on a mechanical
> analysis, not how wing
> shape and aspect are similar to flying birds today
> or the assumption that
> *Archaeopteryx* was a fully capable flapping flyer,
> a similarity I note
> throughout _Dinosaurs of the Air_. Very few
> biomechanical analyses have
> been made on fossil birds in this regard, and its
> about time we start.
> Well, get the ones that aren't published finished
> and published, anyway.
> 
> R: H is setting up more strawman arguments here. As
> per my statement, the 
> fact that the arm wings were about as large as those
> of birds, and consisted 
> of fully developed aerodynamic feathers, shows there
> is no doubt they could 
> generate all the lift needed for powered flight,
> ergo they had the potential 
> (read the word H), to power fly via flapping.
> I do not "assume" Archaeopteryx could power fly. In
> DA I go into great detail 
> showing why Archaeopteryx is much better adapted for
> powered flight than any 
> known glider. Gliders tend to have smaller airfoils,
> and lack flapping 
> skeletal adaptations and muscle supports which Arch
> has. Since the winged 
> dromaeosaurs are much better adapted for powered
> flight than Arch as I detail 
> in DA, they were better powered fliers than the
> latter.  
> 
> <The large size of the wings is readily apparent in
> the articulated type
> M. gui. To consider these enormous, fully refined
> arm wings merely
> maneuvering control surfaces, or compare them the
> dinky little,
> symmetrical, frayed edged feather arrays on the wee
> arms of Caudipteryx,
> is absurd.>
> 
>   I really doubt they were frayed. The entire
> skeleton of the specimens of
> those that have the best preserved wings are nearly
> wholly disarticulated,
> often lacking all of the dorsals, the hips are
> disarticulated, and the
> legs hardly in their natural positions (this is
> especially true of the
> holotype), which argues that the "fraying" is
> evidence of dessication and
> trauma to the animal postmortem. The vanes of the
> wings of better
> articulated specimens, such as BPM 0001, do not show
> this "fraying" and
> the rachis, unlike the type NGMC specimen has
> curvaceous rachi, hardly a
> natural condition. As for the "enormous" wings of
> *M. gui*, what is the
> comparison based on?
> 
> R: H, as I explained in my posts, the wing area/mass
> ratio of the winged dr
> omaeosaurs plots in the middle of the avian range.
> That is enormous by 
> definition, since flying birds have enormous arm
> feather arrays. 
> BPM 0001 has unfrayed arm feathers? It hardly has
> preserved feathers at all 
> according to the original descriptions in 2000. The
> authors did not even 
> bother to describe the feathers of 0001 or 12430. I
> examined the small hand 
> feathers of NGMC and they are frayed in a manner
> similar to the reduced wings 
> of the nearly flightless kakapo.  
> 
> <As I detail in DA, the Johel dromaeosaurs have a
> large set of arm,
> pectoral girdle, and trunk adaptations for advanced
> flight not present in 
> Archaeoptryx, which itself was probably a competent
> powered flier, not
> just a glider. In no regard are the flight
> adaptations of the
> dromaeosaurs'  forelimbs inferior (read the
> descriptions of the various
> Johel coracoids and study the illustrations
> carefully).>
> 
>   These birds lacked a sternal keel [R: also true of
> bats and confuciusornid 
> grade birds], humeral elevator [R: you mean fully
> developed avain system, 
> absent in bats and and confuciusornid grade birds]],
> reduced lateral
> coracoid edge [R:so?], lower coracoid tubercle,
> unfused uncinates to ribs [R: 
> entirely absent in flying screamers, did you bother
> to carefully read DA and 
> look at the pretty pictures I labored over?], fused
> carpus [R: absent in pterosaurs and bats], broadened
> proximal digits of the 
> 
=== message truncated ===


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