RE: Bipedal apatosaurs and stegosaurs?

["Cunningham, Betty" <Cunningham@sega.com>]

GSP said:

> I therefore speculate that Stegosaurus, Apatosaurus and dicraeosaurs
> often walked on just two legs.

Rob said:

>>In order for this senario to be accurate, it would require the
>>animal's center-of-gravity (CG) to be located directly above the hips
>>(providing good balance).  I'm afraid I don't see this in the mounts
>>I've observed.  Using the Diplodicus skeleton in the Science Museum of
>>Minnesota as a reference, it appears that the CG is located at the
>>animal's lower midsection.  .

(speculation:behavior)
     I still believe that the sauropods most effective feeding method   
would be for the larger animals to 'walk' up a tree trunk with their   
heavily clawed front feet as stabilizers for the inital placement of the   
front feet on the tree, and then to walk or lean into the tree so as to   
knock it over or at least get it to tip mightily.  This has the advantage   
of bringing the tastier leaves down past any prior 'browse' level, and   
allows the younger and shorter sauropods to also have access to the   
leaves normally left above the browse line.  Not that this would have   
been an exclusive method of feeding, but that they were able to take into   
advantage this sort of behavior as modern elephants will also   
occasionally do. When starving elephants will strip a tree down to the   
ground, but when nibbling as they go, they just browse with what's in   
reach and don't seem to be quite as destructive.
     Which MIGHT account for the lesser weight on the front legs, as   
these need to be able to rear up (as suggested by GSP) against the total   
weight of the animal, without needing the center of gravity to shift as   
much as walking bipedally as an upright locomotion would.  And MIGHT have   
a reason for the heavily clawed front toes.  And would allow for   
shorter(younger) animals in the herd to survive along side taller(older)   
animals that would (obviously) raise the 'browsing' area above that of   
the shorter animals..

 -Betty Cunningham

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