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Mei example



Reading the description of Mei I am struck by how so many characters once 
thought to be exclusively avian and linking Archaeopteryx and birds above all 
other theropods are showing up in basal dromaeosaurs, troodonts, 
oviraptorosaurs 
etc. Also how the latter basal forms are much more avian than the once better 
known later members of their groups. 

So basal deinonychosaurians appear to be birdy in lacking a postorbital bar* 
and contact between the squamosal and quadratojugal, and having a small 
antorbital fenestra, saddle-shaped cervical articulations, large ventral 
projections 
at the neck base, and a short femur. The presence of these features in basal 
sickel-claws and their subsequent loss in flightless forms is fully compatible 
with the . neoflightless hypothesis, and leaves Archaeopteryx with little if 
anything to place it closer to modern birds than the above dinosaurs. Instead 
deinonychosaurians had avian features not found in Arch including loss of the 
ectopterygoid process*, big sternal plates, ossified sternal ribs and 
uncinates, flattened central fingers, and longer primary feathers. If anything 
the 
sickle-clawed dinosaurs were more derived and better fliers than earlier 
Archaeopteryx. Ergo the presence of well developed flight feathers and other 
avian 
attributes such as the tucked in sleeping posture did not appear deep in 
theropods and well before the advent of flight. Instead the supposed 
exaptations for 
flight are adaptations for flight, latter retained or modified for nonflight 
purposes by later avepectorans. Why researchers continue to insist that 
Archaeopteryx and birds form a clade above deinonychosaurs, oviraptorosaurs etc 
escapes me. 

* As I note in DA, it has yet to demonstrated that Archaeopteryx lacked a 
postorbital bar, although this is certainly possible. What is certain is that 
Archaeopteryx lacked the avian pterygoid-quadrate articulation reported by 
Elzanowski and in the Milner et al Nature paper on the braincase etc of the 
London 
specimen. If the pterygoid and quadrate are articulated in the manner they 
suggest then the normal archosaurian quadrate ramus of the pterygoid present in 
the Eichstatt and Munich specimens cannot articulate with the equally big 
pterygoid ramus plate of the quadrate, and instead projects well posterior to 
the 
quadrate shaft - an anatomical impossiblity and absurdity! The supposed 
quadrate 
articulation described by Elzanowski is actually the ectopterygoid process of 
the pterygoid, as I detail in DA.