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Protoavis (was Re: solnhofen)
Rob Gay wrote:
Indeed, most of _Protoavis_ seems to be made up of several animals.
I don't believe there has been a definitive publication which directly
addresses (a) that _Protoavis_ is certainly a chimera or (b) if so, the
identity of the specimens that make up the chimera. Rob, if you know of
such a paper, let me know! :-) If it's not published... well, you know...
The skull is part of a megalancosaurid,
Silvio Renesto found uncanny similarities between the skull and neck of
_Megalancosaurus_ and the skull and neck of _Protoavis_. He could find no
obvious siimilarities between the two in the rest of the skeleton. Hence,
Renesto speculated that the skull and neck of _Protoavis_ *may* belong to a
Incidentally, John Ruben has been keen to link _Megalancosaurus_ to the
origin of birds. It has a superficially bird-like skull (= triangular in
profile; apparently that qualifies as "bird-like"), elongate scapula, and
certain postcranial features which suggest that _Megalancosaurus_ might have
been a gliding animal (all challenged by Renesto, who restores
_Megalancosaurus_ as a tree-climbing, non-gliding chameleon-like animal).
Drepanosaurids are basal archosauromorphs, and as such are no more relevant
to the origin of birds than (for example) _Tanystropheus_.
the hindlimbs are non-avian theropod,
the "hand" is some archosaur with a crocodile-normal ankle, and wait for
the paper on the pectoral girdle. However, it is generally >accepeted (from
what I know), that the verts are something new (and >are what I refer to as
Again, you appear to have some inside information.
However, due to the chimerical nature of the rest of the specimen, this is
usualy looked over.
Other note on early birds...apparently there are bird tracks in the L.
Jurassic Kayenta Formation...
L. = Lower. These might be nonavian theropod tracks. Unless the
bird/theropod dropped dead on the spot after making the tracks, and was
preserved along with them, then it may be very difficult to draw the line
between bird and bird-like theropod solely (no pun intended) on the basis of
Thanks for a very interesting post!
Timothy J. Williams
Iowa State University
Ames IA 50014
Phone: 515 294 9233
Fax: 515 294 3163
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