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Re: Concavenator corcovatus, a new humped carcharodontosaurid from Las Hoyas




On Thu, 9 Sep 2010, Tim Williams wrote:
"Jura" <pristichampsus@yahoo.com> wrote:

Sad, it really just reads like the authors want these
to be quill knobs more than anything else. Maybe the actual
paper offers better insight.

Hmmm... I really don't see why the idea of quill knobs in a carcharodontosaur is so controversial. We already know that _Velociraptor_ had them. _Velociraptor_ couldn't fly, and there's no compelling evidence that it evolved from flighted ancestors. So _Velociraptor_ tells us that the presence of quill knobs cannot be assumed to indicate flight ability. _Concavenator_ tells us that quill knobs can exist in non-maniraptorans.

One possibility is that the quill knobs anchored spike-like integumentary structures along the ulna in _Concavenator_ and _Velociraptor_. These spikes may have therefore been quite widespread among theropods, but did not always leave an osteological 'footprint' (= quill knobs).

This isn't my idea, but comes from Darren Naish over 10 years ago:

"Another thought it that some non-avian theropods could have modified
their primaries into stiff, spike-like structures that could not have
been fouled or snapped in predatory strikes."

http://dml.cmnh.org/1999Feb/msg00470.html

Curious, how many "predictions" from this list have come "true"?