Re: new boook on functional morphology

[pharrinj@PLU.edu]

On Thu, 18 Jan 1996, Ronald Orenstein wrote:

> >Recently discovered ceratopsian trackways have definatively countered
> >Johnson & Ostrom's reconstruction of a sprawling gait. The trackways
> >are consistant with either an erect gait or a bow-legged gait (if
> >the manus was held twisted outward), but NOT with a sprawling gait.

..snip...
 
> could we not consider it possible that for
> some purposes (possibly including head-to-head shoving matches) ceratos
> might have adopted a sprawling posture that was not used during normal
> walking?  
> 
> So if all Ostrom did was to show that the pectoral girdle was consistent
> with a sprawled posture (say), then one could speculate that such a posture
> was used - but NOT while the animals were busy laying down trackways.

I BELIEVE that Johnson and Ostrom claimed that the structure of 
the ceratop(s)id pectoral girdle was *inconsistent* with an erect gait 
(i.e. that the bones did not fit right when put together in an upright 
configuration.  My guess (and it's only a guess) is that they made some 
incorrect assumptions about how the girdle attached to the body.

> 
> Does this make any sense?
> --

Perfect sense (but apparently not to J&O).

> Ronald I. Orenstein                           Phone: (905) 820-7886 (home)
> International Wildlife Coalition              Fax/Modem: (905) 569-0116 (home)
> Home: 1825 Shady Creek Court                  Messages: (416) 368-4661
> Mississauga, Ontario, Canada L5L 3W2          Internet: ornstn@inforamp.net
> Office: 130 Adelaide Street W., Suite 1940    
> Toronto, Ontario Canada M5H 3P5             
> 
>