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Re: DA reviews
Tim Williams (firstname.lastname@example.org) wrote:
<For the gazillionth time, no one has suggested that birds evolved *from*
deinonychosaurs, any more than humans evolved from chimps. The two are proposed
to be sister groups.>
To my knowledge, the lineage-segment advocates _do_ argue, as most
anthropologists apply the phylogeny, that chimps _did_ give rise to humans, as
much as australopithecines gave rise to hominines, because they are "obviously"
more primitive. At least Tim White's commentaries have applied a non-cladistic
theory to this affect, advocating a lineage-driven, pseudo-Linnaean style rather
than a cladistic perspective.
<The specialized pedal digit II is also seen in _Rahonavis_ (a bird!) and
troodontids. _Microraptor_ has one too - and Feduccia suggests that
_Microraptor_ should be removed from the Dromaeosauridae! [Says Feduccia: "In
addition, the recently described four-winged dinosaur from China (Xu et al.
2003 ) appears to be much more birdlike than dromaeosaurlike, and its supposedly
diagnostic dromaeosaur tail (also like that of a ramphorhynchoid pterosaur) and
claws bear little close resemblance to those of the typical dromaeosaurs such as
_Deinonychus_ and _Velociraptor_.] Says who?
Dromaeosaurid-like tails are also seen in _Shenzhouraptor_/_Jeholornis_ (a
But not to such a degree that there is a "ramphorhynchoid" [sic, which I'd
always known was not a anagram -- my previosu use of this phrase was to point
out whose mispelling it had been] tail in *Rahonavis,* *Shenzhouraptor,* or
*Jixiangornis,* (I actually am coming to some disagreement that *Jeholornis* is
the same as *Shenzhouraptor,* based on some cranial and appendicular/pevlic
features that are inconsistent based on current material). Note also that the
previous author and Ruben et al. had also argued that *Rahonavis* was _not_ a
bird because of supposedly lacking a hypopubic cup and that the wings,
persistently argued for a few years though not currently applied, belonged to
Jaime A. Headden
Little steps are often the hardest to take. We are too used to making leaps in
the face of adversity, that a simple skip is so hard to do. We should all learn
to walk soft, walk small, see the world around us rather than zoom by it.
"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)