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Re: Feduccia et al. (2005) Critique
Banded pigmentation is also occasionally found in the bird feathers from
the formation, so if the non-avian dino integument is collagen rather
than keratin, then Feduccia must come up with an explanation as to why
color banding would evolve in a tissue that is hidden from view on a live
animal. Or he must come up with a taphonomic explanation that doesn't
involve a lot of arm-waving.
I'd like to see a rigorous geochemical study done on the pigmented
segments vs the non-pigmented segments on these specimens. It would be a
destructive analysis, but very little material would be needed.
On Mon, 17 Oct 2005 18:41:48 -0400 Jon Barber <firstname.lastname@example.org>
> At 02:25 PM 10/11/2005 +0000, Michael Mortimer wrote:
> >The BAND movement simply refuses to die, invigorated as it is by
> >transformation into MANIAC. It seems like just yesterday that I
> shot down
> >Martin's latest publication
> >now I get to do the same for Feduccia's. Well, technically
> >and Hinchcliffe are coauthors, but I mostly refer to Feduccia
> >below for simplification.
> >Feduccia, A., Lingham-Soliar, T., and Hinchliffe, J.R. (2005). Do
> >feathered dinosaurs exist? Testing the hypothesis on neontological
> >paleontological evidence. J. Morphology (in press).
> >The article starts out with an introduction full of fun
> [big snip]
> >When it comes to Sinornithosaurus' holotype, it's hard to see where
> >Lingham-Soliar is going. No doubt affecting this is the fact the
> >is hopelessly blurry. He claims the base of the illustrated tuft
> >filaments is actually an eroded area with filaments that run
> diagonal to
> >the main tuft.
> This *may* be a second tuft hidden in the matrix under the first.
> > Perhaps true (I can't evaluate the figure), but Xu et al. (2001)
> > mentioned several instances of tufts. Lingham-Soliar argues a
> case of
> > filaments branching from a central one is due to the "laws of
> > which is fine, but again Xu et al. stated several of these
> > were present. He also states that integumentary structures are
> > throughout the substrate, including fainter (more eroded?) ones
> > almost the entire surface. I don't see how this argues against
> > being feathers.
> >Given the quality of Lingham-Soliar's figures for Sinornithosaurus,
> >found his statement "... the conclusions arrived at by Xu et al.
> >are not only seriously flawed and technically unsound but
> misleading to
> >the reader both by the extremely poor quality of their figures
> >(uninformative in vital respects) ..." hilariously ironic.
> Something else that puzzles me about the _Sinornithosaurus_ section
> is the
> fact that the "protofeathers" originally depicted in Xu et al.
> appear to
> have pigmentation, whereas a lot of the strands illustrated in the
> paper don't seem to. Unfortunately, as you point out, the pictures
> the best, and make it hard to tell what's going on. Some of the
> pointed to may have become separated from the larger tuffs before
> >Pelecanimimus is less convincing. There are supposedly overlapping
> >on the forearm, some with "fingerlike projections". These are
> >photographed (though not in relation to any bones), but they don't
> >immediately strike me as scales. At least not dinosaur scales.
> They seem
> >to be diamond-shaped, like you'd find on a gar. Maybe
> Pelecanimimus did
> >have rhomboid overlapping arm scales. I can't help but think of
> >Santanaraptor though (which Feduccia et al. mention as an unnamed
> >theropod), which the authors describe as having "a thin epidermis,
> >mostly by irregular quadrangles bordered by deep grooves in a
> >pattern." Amusingly, if the authors are right, this destroys their
> >argument dinosaurs lacked overlapping scales, so couldn't evolve
> >(under Maderson's outdated developmental scheme).
> The caption for figure 15B states "Skeletal reconstruction of
> _Pelecanimimus_ (modified from Carroll, 1988)", but _Pelecanimimus_
> described until 1994, and the closest thing I can find in Carroll is
> illustration of _Struthiomimus_ (figure 14-9). Is it kosher to label
> modified reconstruction as being of one dino when in fact it's of
> or am I being pedantic?
> Regarding _Caudipteryx_, Feduccia et al. state that "According to
> paleontological theory, everything related to the lineage of avian
> must be developing flight from the ground up and all aerodynamic
> adaptations, regardless of their aerodynamic precision, must have
> in a context other than flight, as preadaptations. 'Non-avian
> such as _Velociraptor_, _Compsognathus_, and _Tyrannosaurus_ were
> terrestrial cursors. Thus, the ancestral mode of life of birds was
> that of
> a cursorial biped. Inferences about the habits of _Archaeopteryx_
> should be
> made within this framework and not the inverse" (Chiappe, 1997, p.
> This line of reasoning completely ignores the obvious bird-like
> features of
> _Caudipteryx_, the fact that oviraptosaurs are likely secondarily
> flightless birds (with _Caudipteryx_ as a basal member), and the
> fact that
> it is not parsimonious to assume that the intricate aerodynamically
> designed detail of the positioning of the remiges of the avian wing
> in a nonflighted theropod (Fig. 26)."
> The Chiappe paper was published in 1997, and _Caudipteryx_ was
> described in
> 1998. Isn't it a bit unfair to criticize Chiappe for ignoring
> when it hadn't even been described yet?
> [snip the rest]