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Re: Brachiosaur flexibility and face-shape

On 28 September 2011 17:12,  <GSP1954@aol.com> wrote:
> It is not entirely certain that the B altithorax coracoid actually belongs
> to the holotype because it's awfully big compared to the ilium (as can be
> seen in Riggs original same scale figure), and to G. brancai coracoids.

Really?  Check out Taylor (2009:fig 4), which can be seen here;

I showed same-sclaed limb-girdle elements Brachiosaurus (FMNH P25107)
and Giraffatitan (coracoid from HMN SII, ilium from Aa 13 but scaled
to SII size).  The Brachiosaurus coracoid looks _a little_ larger than
that of Giraffatitan, but nothing outstanding.

> I cannot easily fit it on the skeletal restoration. And I suspect the 
> laterally
> facing glenoid is due to poor ossification.

My guess would be, rather, that if it's not a genuine distinguishing
feature, it's due to _excess_ ossification, as with the Kentrosaurus
ulna figured by Mallison (2010b:fig. 3B-D).  That's rather an exciting
prospect, since if it's true then it tells us something about the
cartilaginous extent of the glenoid in sauropods generally.

> It is not possible to accurately restore the exact posture and action of
> long necks from the bones

These eighteen words should be tatooed on the insides of the eyelids
of everyone who works on sauropods.


Mallison, Heinrich.  2010b.  The digital Plateosaurus II: An assessment
of the range of motion of the limbs and vertebral column and of
previous reconstructions using a digital skeletal mount.  Acta
Palaeontologica Polonica 55(3):433-458.  doi:10.4202/app.2009.0075

Taylor, Michael P.  2009a.  A re-evaluation of Brachiosaurus altithorax
Riggs 1903 (Dinosauria, Sauropoda) and its generic separation from
Giraffatitan brancai (Janensch 1914).  Journal of Vertebrate
Paleontology 29(3):787-806.