Re: Unwin's high horse

[Dann Pigdon <dannj@alphalink.com.au>]

 David Peters wrote:
> _All _ pterosaurs were capable of both bipedal and quadrupedal locomotion.

James R. Cunningham replied:
> 
> I don't believe this to be the case. I can't imagine a Quetz being able
> to achieve long-term bipedal stability.

Not in the long term. However...

I'd have found it hard to believe that a frill-necked dragon could move
bipedally, too, if I hadn't seen it myself. I believe most pterosaur
pelves that have been preserved in three dimensions indicate a
sprawling gate, better suited for quadrupedal locomotion when moving
slow. However, if these animals needed some sort of take-off run, then
clearly they must have been able to move bipedally at least for short
distances. 

Of course I don't see them taking long ambling strolls on their hind
limbs alone. Equally, I don't buy the idea that they all threw
themselves off high places to become airborne. Hence a brief take-off
run was probably used by at least some species (during which they were
technically bipedal, if only briefly). It didn't have to be pretty, or
super-efficient. Albatross aren't the most graceful of bipeds either,
but they get the job done.

-- 
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Dann Pigdon                   Australian Dinosaurs:
GIS / Archaeologist         http://www.geocities.com/dannsdinosaurs
Melbourne, Australia        http://www.alphalink.com.au/~dannj/
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