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PAGATIA DO NOT MEAN VOLANT ANCESTRY
Keeping up with the promise about becoming more involved on the list
(its not that I didn't have time, its the stupid extinction and brooding
threads) here's my POV on pagatia and their evolution.
There are few osteological correlates for pagatia, they really don't
leave any signs. So far, the earliest evidence for a pagatium (in the
dino/bird lineage) is the Early Cret. enantiornithine? _Noguerornis_ and
(possibly) in _Confuciusornis_, but not in _Archaeopteryx_. As far as I
can tell, _Caudipteryx_ and _Protarchaeopteryx_ both lack a pagatium.
The arm posture found in _Oviraptor_ and all other maniraptoriforms
including birds is not really indicative of a pagatium. Most others,
most notably Larry Martin have argued that the arm "folding" in birds
(and by extension dinosaurs) evolved to pack the wing feathers against
the body in a compact structure. This motion is by itself a step from
the flight stroke or other forelimb motions. So really, the evidence
points more towards some large forelimb feathers in maniraptoriforms.
Anyway, even if pagatia are present, they do not mean volant ancestry,
more likely a gliding ancestry.
FORELIMB FEATHERS DO NO MEAN VOLANT ANCESTRY EITHER
Let me reiterate; PHYLOGENY MUST PROVE SECONDARY FLIGHTLESSNESS, NOT
BIOMECHANICS, GUESSWORK OR ANYTHING ELSE.
Within the animal world "flight" features have not always meant "descend
from a volant ancestor". Read some Rayner and the refs within his
papers, maybe some Scholey too; gliding and climbing animals show many
"flight" features that cannot be seperated from true flight features in
true volant animals. And sometimes the converse is true.
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