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RE: On Conchoraptor?
Jaime A. Headden wrote-
The abstract really tells much of the story. In comparing the edocasts
between Concho, Archie, and an ostrich, Kundrát finds that the oviraptorid
brain is much more like that of the ostrich than is Archie's, implying it
derived from volant ancestors.
In all fairness, Kundrat finds most of the characters in the oviraptorid
braincase are less birdlike than Archaeopteryx, with a few being more
birdlike. The only aspect Kundrat believes could be due to
neoflightlessness is the position of the optic lobes. His reasoning here is
highly flawed though-
"The fact that Struthio, a recent secondarily flightless bird, has the same
cerebral superimposition of the optic lobes (CSOL) pattern as Enaliornis, a
Cretaceous flying bird, evokes the hypothesis that similar CSOL pattern of
Archaeopteryx, a flying Jurassic bird, should be expressed by Conchoraptor
if it would be a secondarily flightless bird as proposed by Elzanowski
(1999) and Maryañska et al. (2002). In fact, the CSOL of Archaeopteryx is
fairly similar to that of Conchoraptor. This would suggest that Conchoraptor
might have evolved from an ancestor with flying capabilities."
First, the sample size used here is pitifully small (wouldn't a comparison
between Struthio and a tinamu be far better?). Second, Enaliornis is not
known to be volant. No forelimb or pectoral material is known, and it's the
most basal known member of a neoflightless clade (Hesperornithes). Third,
Archaeopteryx itself may not have been volant.
Incidentally, the tinamu Crypturellus does have optic lobes ventral to the
posterior part of the cerebral hemispheres as in Struthio (Franzosa, 2004).
So do Anas, Chauna, the basal undescribed troodontid IGM 100/1005,
Saurornithoides junior, pterosaurs and.... Allosaurus?! So unless
Olshevsky's right.... ;)
I agree with Jaime's comments regarding phylogeny, the taxonomic identity of
ZPAL MgD-I/95, the questionable EQ, etc..