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Re: So here it is...



David Marjanovic wrote-

> BTW, I stated that all preserved feet of *Archaeopteryx* are badly crushed
> and not fully preserved. The situation is more complicated than this (and
no
> one has objected... ~:-/ ): I was referring to the London specimen. The
> halluces of the Berlin specimen aren't prepared, and those of, I think,
the
> Eichstätt specimen are fully preserved and reverted; however, these, too,
> are two-dimensional, so how far they were reverted is still another
> question. Anyway, the halluces of *Microraptor* are longer and attached
more
> distally.

I haven't objected to your statement because it's impossible to prove
halluces were reversed if a specimen is two-dimensionally preserved.
Because there is no osteological feature that can be used to articulate the
first metatarsal with the second, you cannot be certain of the state in
two-dimensionally preserved specimens.  Only three dimensional specimens
like Velociraptor (IGM 100/985), an oviraptorid (IGM 100/979) and Rahonavis
can be proven to be one way or the other.  Both the Eichstatt and Solnhofen
specimens of Archaeopteryx have pedes preserved with the hallux reversed.
You could take this to mean this is the condition in life.  However, looking
at Confuciusornis sanctus shows that some specimens (GMV-2130, GMV-2131,
left foot of GMV-2133) have reversed halluces, while others (right foot of
GMV-2133, GMV-2141) do not.  Because of cases like this, just how much can
we trust two-dimensionally preserved specimens are non-reversed
(Compsognathus, Sinosauropteryx, Sinornithosaurus, Microraptor) or reversed
(Caudipteryx, Changchengornis, Confuciusornis dui, Iberomesornis, etc.)?  I
personally just trust the orientation preserved to be the correct one and
code C. sanctus as having a reversed hallux because the majority are
preserved that way, but I can't defend this position.

Mickey Mortimer