Re: Sauroposeidon

["Timothy Williams" <twilliams_alpha@hotmail.com>]

Nick Pharris wrote:

> So were basal titanosauriforms all as high-shouldered as _B. altithorax_ 
> and
> _G. brancai_, with later titanosaurs re-equalizing their limb lengths?

Here's what I think.  _Brachiosaurus_ (and maybe _Giraffatitan_ - and 
_Euhelopus_ too?) may represent a branch of basal titanosauriforms that 
became very high-shouldered, due to elongation of the forelimbs (especially 
the humerus).  They also show the anterodorsal inclination of the sacrum 
associated with this sloping from shoulders to hips.  Curiously, this foward 
and upward "tilting" of the sacral axis is seen in _all_ titanosauriforms, 
even those (like true titanosaurids) which have approximately equal fore- 
and hindlimb lengths.  This means that their backs must have gently arced 
from the shoulders to the hips.


> Or is
> it not entirely certain that both _B._ and _G._ were as high-shouldered as
> traditionally depicted?

I think it's OK for _B. altithorax_, but I'm not sure about _Giraffatitan_ 
or those poorly known Wealden "brachiosaurs" (_Pelorosaurus_ etc).


Tim

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