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Re: SAPE Proceedings: papers of mass distraction



Stephen Pickering (stefanpickering2002@yahoo.com) wrote:

<2) Marco Pavia/Cecile Mourer-Chauvier's purported owl, Athene trinacriae
is "diagnosed" on the basis of descriptive comparisons of disarticulated 
limb elements, not on any one can use to examine relationalities (PAUP is
not used in this paper, and some of the volume's contributors need an
introduction);>

  Some species from the Messel, from the Green River, and especially the
London Clay, are described on the basis of small, miscellaneous bits or
one thing only. However, many ornithologists, including Gareth Dyke,
Gerald mayer, and Cecile Mourer-Chauviré [note spelling] have described
several species on the basis of what are in fact very diagnostic humeri,
tibiotarsi, and coracoids; this is true of Varricchio's new bird from the
Two Medicine Formation, *Piksi*, which is based on only a few isolated
elements, or the ?hesperornithiform *Potamornis* (Elzanowski, Paul &
Stidham) based on a quadrate. Sterna also vary predictably within living
birds permitting ease of referral and diagnosis, and these fellows are
very knowledgeable, despite one's inability to render in PAUP a phylogeny
comprising of a coding for only 1-3% of the matrix.

<3) Jorge Noriega/Herculano Alvarenga on Tertiary anhingas from South
America, refreshingly, does not erect new taxa on the basis of no
evidence;>

  You will note that in modern ornithology, size variation in birds is
indicative of population variations, unlike in reptiles, because birds
have a gross size "iron ceiling" that do not cross during ontogeny. Noting
a taxon as adult and saying its bigger than that, smaller than that, its
humerus is a tad longer but the sternum a tad shorter, is pretty much how
nearly all Liaoning taxa have been described, and so far only a few of
them appear to be synonymous. This may change, but this happens in modern
birds as well, and they are supported but genetic percentage variations.

<7) David Parris/Sylvia Hope (see # 6) could have presented an exegesis of
bone fragments, but why clutter the literature with yet another nomen
dubium?>

  And what expertise in bird bones have you to judge the nature of an
avian nomen dubium? These people have been studying birds for between ten
to thirty years, their entire adult, scholarly career. I would ask _them_.
Both authors are, I beleive, alive and well in London.

<8) Sankar Chatterjee's paper is, likely, the most important paper in the
volume, an end Cretaceous, Antarctic Peninsula loon with a skull and
partial skeleton, Polarornis gregorii, subjected to PAUP 3.1. Its
positioning within late Cretaceous clades needs further investigation;>

  Wow. *Polarornis*, the bird that has to be seen to be beleived. Yet the
ornithologists have been stymied by crap, and Chatterjee's excellent
dissertation on similarities between hesperornithiforms and loons as being
phylogenetic in nature is incredible, or his discourse of the
relationships (including a book) of a possible chimaeric assemblage he has
yet to respond to claims of drepanosaur relationship. Again, drawings of
the skull I've seen of *Polarornis* are interesting, curious, and quite
frankly, amazing, in the similarities, so I have no problem coming to this
conclusion myself. I'm just a lot more skeptical.

<10) The paper by Junchang Lui,>

  Lü -- I have the paper before me. That is, on a standard keyboard
(ASCII), depress and hold ALT, then in sequence, 1, 2, then 9, releasing
each numeral in order to the next. This gives us "u" with an umlaut.
Chinese/Japanese/Mongolian typography should read, surprising in a Chinese
publication otherwise:

  Lü Lunchang, Dong Zhiming, Azuma Yoichi, Barsbold Rinchen, & Tomida
Yukimitsu.

<Zhiming Dong, Yoichi Azuma, Rinchen Barsbold, and Yukimitsu Tomida on
"Oviraptorosaurs compared to birds" is fascinating, and, perhaps, Mickey
Mortimer or Tom Holtz can be convinced to examine the paper's PAUP data
matrix and compare it to their work for correction/elaboration. The
authors believe "oviraptorosaurs are group of flightless birds"
[sic]...but since Aves is a clade within Dinosauria, and all "birds" are
theropods, the authors' attempts to, somehow, disassociate "birds" from
"dinosaurs" is one of those endlessly frustrating semantic roller
coasters;>

  Mickey has already expounded on the addition of taxa and recoding which
alters the topology. The matrix is essentially Chiappe's birds + mononykes
matrix without the mononykes, add in oviraptorosaurs, exclude
therizinosaurs, "we want to test the idea that oviraptorosaurs or
dromaeosaurs are closer to birds idea". The matrix is not very tenable,
and there are numerous miscodings, which Mickey noted a year ago when he
tested codings he observed in Chiappe's original, 1996 matrix (as
published in _Memoirs of the Queensland Museum_, he names *Patagonykus*
there). it would be wiser to resort to recent Xu & AMNH matrices for what
are more comprehensive bird sister-group studies. The skeleton offered is
interesting in having eight sacrals and a loose quadratojugal/quadrate,
which even Maryanska and Osmólska noted for *Conchoraptor* (several skulls
they studied were of that taxon), despite the shared condition of a
platform the qj sat on that would have restricted the movement of the
bone. The authors (Lü et al) do not make the obvious inferrence that this
would be related to streptostyly, and then test it: the fact is, the
quadrate is firmly fixed to the palatal complex in a rigid, fused
stricture, and the quadrate/braincase articulation is also very "fixed"
despite its monocephalic condition. This should have put warning flags up,
but the matrix they had was not designed to test for this, and this is sad
to use _it_ instead of something more recent....

  Cheers,

=====
Jaime A. Headden

  Little steps are often the hardest to take.  We are too used to making leaps 
in the face of adversity, that a simple skip is so hard to do.  We should all 
learn to walk soft, walk small, see the world around us rather than zoom by it.

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