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Re: Oryctos Is Back
David Marjanovic worte:
<In 2006, at the 2nd International Palaeontological Congress, Larry Martin told
me that he had some ongoing work on 50 specimens (!) that showed *Microraptor*
was _too_ capable of sprawling. This was, IIRC, supposed to be published soon;
in any case I didn't get another answer when I asked how sprawling was
compatible with the photos in Hwang et al. (2002).>
In the flying dinosaurs Nova special, several individuals had used supposed
large ilia that were isolated from the matrix and cast as 3D elements that they
used to assert the ability of the femur to evert laterally. Larry Martin was
involved in this topic as was, I think, Dave Burnham; Martin especially was
shown manipulating the elements. The major criticism of the segment I think was
that all the elements were skewed for flattened, and thus would not have
inhibited eversion of the femur any more than it would have permitted the
experimentalists from being able to correctly assess leg movements by "running"
them into a stride-motion simulation. It is a pity they haven't described
these, since it looked as if the slabs the authors were using as "Microraptor"
were several feet too large to account for as *Microraptor*.
In Martin's cladogram, "Microraptor" is treated in quotes as here.
Furthermore, the author addresses the fronds on *Longisquama's* back as though
they were paired -- something that has never been proven in the specimens --
and has illustrated an avian-style set of fronds on the tail to somehow
exaggerate the avian-ness of the restoration. In noting the substructure of the
fronds, he has asserted that the fronds are unsegmented, or "unopened" as in
*Confuciusornis* tail plumes, and argues this is adequate to assert they are
true feathers. It is not. He seems to have run away from the arguments (Reisz
and Sues) on the microstructure as provided by the critique to the paper (Jones
et al.) that seems to have fueled this theory.
Jones, T.D., Ruben, J.A., Martin, L.D., Kurochkin, E., Feduccia, A., Maderson,
P.F.A., Hillenius, W.J., Geist, N.R., Alifanov, V. 2000. Nonavian Feathers in a
Late Triassic Archosaur. _Science_ 288:2202-2205.
Reisz, R.R., Sues, H.-D. 2000. The âFeathersâ of *Longisquama*. _Nature_
in addition, in 2001, Prum, and Unwin & Benton replied to Jones et al., and a
final response by Jones et al. followed this in
*Longisquama* fossil and feather morphology. Science 291:1899-1902.
Jaime A. Headden
"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)