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Re: coelurosauravus revisited



David Marjanovic wrote:

6. The affinities of Coelurosauravus are still an open question. The metacarpals and metatarsals decrease in length laterally from II to V. When we find another taxon with this pattern, we might have a clue.

Why can't that be an autapomorphy?

I agree with David wholeheartedly. Can we get away from the mindset that one weird feature can disqualify a taxon's membership of a clade? Czerkas tried this stunt in his "phylogeny" of theropods, and put forward all sorts of weird ideas about the evolution of theropod hands.


So what if _Coleurosauravus_ has a weird metapodial morphology? Many other characters put _Coelurosauravus_ close to _Longisquama_ and drepanosaurids, at the base of the Diapsida.

7. The hands and feet, to no one's suprise, appear to be webbed.

You mean "to everyone's surprise". What for would an arboreal animal need webbings that I at least can't see in the bad photo?

I'm not surprised. If webbing is indeed present in _Coelurosauravus_ (and I'm not saying that it is), then it would make sense for a gliding animal. Flying frogs (e.g., _Rhacophorus_) have webbed hands and feet, and so do many other aerial gliding animals that launch themselves from trees. Colugos (flying lemurs) have an interdigital patagium, and are called "mitten gliders" for this reason.


BTW, any one know WHY this beastie is actually called _Coelurosauravus_? I much prefer the junior synonym _Daedalosaurus_; but, alas, the name _Coelurosauravus_ has priority.



Tim

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