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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.

PAGATIA

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.

Clear?

Matt Troutman

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