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Re: Coelurosauravus: glider? or bluffer?
some wrote about skull bones, mandibles and clavicles
being dermal in origin:
dp: yes, but you're going back to fish here. In Coelurosauravus it's
like going back to dermal ossicles, like Stegosaurus or horned toad
spikes. Scales gone crazy.
This still isn't evidence for the absence of muscles and the like.
some wrote of the human hand having similar metacarpal proportions.
dp: please stay on the same merry-go-round. Anything diapsid and
Permo-Triassic would be better. And all other arboreal diapsids did not
adopt this pattern.
Perhaps it has something to do with an opposable thumb??? Just a
suggestion -- which intends to say that you shouldn't give this one
apomorphy so much weight.
regarding the anterior process of the ilium and bipedalism: It only
takes a tiny nubbin of an anterior process in extant lizards to put
them in the bipedal camp. Which makes it easier, if you like analogies,
to attribute bipedalism to species we will never meet.
Things like the ratio of hindlimb length to trunk and tail length should
also be taken into account... as well as the morphology of the forelimbs...
Again, as in bats and birds, the fore limbs/fins of flying fish are
chained to internal bones and muscles, unlike the skin of
The fin rays do not form joints or other firm connections with the
endochondral bones of the fin. They are a very good analogue for the wing
rods of *C.*.
On another subject: I looked at the pes of Eudibamus, the purported
Permian biped. It looks like it does have everything a bipedal lizardy
reptile would need, except that the pes is so incredibly asymmetric that
Eudibamus would essentially be running on toe four alone.
I'd say it's functionally tridactyl -- just not with toes II, III and IV
like a theropod, but instead with toes III, IV and V. Like a kangaroo, sort
of. (The Pleistocene *Procoptodon* had even lost all toes except IV! It was
monodactyl like a horse!)