RE: vaulting pterosaur launch, questions

[Tim Williams <twilliams_alpha@hotmail.com>]

Scott Hartman wrote:


> True enough, although those taxa have torso's that are dorsoventrally 
> flattened, allowing the stomach (and the tail in Ptychozoon) to be 
> utilized as airfoils, and ones that have substantially more surface 
> area than the webing of the digits.  In addition both Ptychozoon and 
> flying frogs show adapations for aboreality.  Niether of these applies 
> to Archaeopteryx, and I think those are fairly key elements of that 
> particular analogy.


Just to be clear: I wasn't advocating either flying geckos or treefrogs as 
analogs for _Archaeopteryx_.   I was just pointing out that distal gliding 
surfaces (like the webbed feet of _Ptychozoon_ and _Rhacophorus_) are useful 
gliding surfaces in their own right.  Thus, there is no reason to assume that 
the wings of _Archaeopteryx_ were unsuitable for gliding simply because of the 
absence of tertials. 


Note that I don't think _Archaeopteryx_ was arboreal either.   But I don't 
think it's necessary to equate gliding ability with an arboreal (or 
"trees-down") origin of flight.


Cheers

Tim
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