Re: CLIMBING

["Matthew Troutman" <m_troutman@hotmail.com>]

<<Yes, but remember that the ultimate primate bipedalism (represented by 
ourselves) originated in trees, as suported by the latest research on 
hominids and australopithecines in general. The afarensis had recurved 
phalanx and oposable big toes and were facultative erect walkers. I 
think all compulsory bipedal animals' evolution has passed through an 
arboreal stage.>>

I was under the impression that this was a vestige.  I'm not sure 
whether I can support climbing as a something that caused bipedalism.  
Macropodids certainly did not gain their bipedal tendencies through an 
arboreal phase, neither did kangaroo rats (I forget the family/genus).  
Anyway, even if hominids are a unique case (I still am skeptical about 
the correlation) this really has little bearing on other bipeds.  You 
have to prove an arboreal descent in bipedal dinosaurs to show that they 
did come from arboreal animals and that their bipedalism WAS caused by 
climbing.  

Another question is: why would an arboreal animal that climbs with its 
forelimbs become a bipedal animal?  This is a valid question.  I think 
that the link between bipedalism and climbing is not really a valid one. 
Most (non-avian) climbers (except _Opisthocomus_) climb using both their 
forelimbs and hindlimbs.  The forelimbs are an integral part of 
climbing.  (Again, I do not know how this would apply to hominid 
primates).  There is no reason for the animal to become bipedal.

Matt Troutman  

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