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Re: other challenges



Kendall Clements wrote:

<...[I] think the most amazing thing about the whole 
episode is that Science published the Longisquama
paper in the first place. The paper lacks any
phylogenetic analysis, includes dubious (and
hypocritical) interpretation of a poorly preserved
fossil, and its conclusion flies in the face of the
vast majority of characters, not to say logic.>

  I must first thank a friend for getting me a pdf
version of the article, with blow-up-able figures for
more detailed examination than the quality in the
magazine-version of the paper itself.

  However, the results of the paper show that the
authors were in fact describing structures and found a
homologue in feathers. Their comparison was quite
vivid, if jilted a little towards feathers, and their
subsequent (and prior) interpretation of these as
"feathers" was ... unscientific. First, they used the
interpretation of barbs and hope of further studies to
find barbules. These are two errors on the part of the
testing -- there are no separate, perpendicular
structures on the vanes of the structures, just
"ridges" and "troughs" and a continuous lamina;
further, they tried to hope for something that no
evidence supported the likelyhood of. Hoping for
barbules in *Caudipteryx* feathers is a maybe, Zhou
and Wang (2000) say no, but a continuous lamina cannot
have such structures.

  Further, I would like to know where the
interpretation of "paired dorsal structures" came
from, when the photos do not seem to support the
intepretation. Did Sharov mention this? Maybe I need
better photographs....

  Again, to back previous posts, they do not say
*Longisquama* is a bird ancestor, but that the fossil
may, with further study, suggest the ancestry of
birds. We are all certain we know the opinion of the
group, but unless the paper explicitly states it, and
it does not, then the conclusions of the paper are to
be taken only as given. These invlolve only the
structure and homology of the dorsal structures, and
that is what we work with, not what we know or think
has been said elsewhere.

  Also, the paper did not invlolve itself with a
phylogeny, just a question of ancestry, to interpret
its conclusions.

<So why did Science publish the article? .... Clearly,
Science can expect the highest rigour when it suits 
them, and throw that all out the window when it
doesn't.>

  They may have felt the most rigrous study to date on
these structures, and unique ones they are, needed a
paper; more controversial theories have been published
in _Science_ and _Nature_, including the asteroid
origin of the K/T clay, separation of Madagascar from
India, etc.

=====
Jaime "James" A. Headden

  Dinosaurs are horrible, terrible creatures! Even the
  fluffy ones, the snuggle-up-at-night-with ones. You think
  they're fun and sweet, but watch out for that stray tail
  spike! Down, gaston, down, boy! No, not on top of Momma!

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