[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]
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
> 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