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Re: Refurbished Berlin Brachiosaurus Mount



Mike:

It's all relative, Kent.  For you or me, 7m would not be bad going;
for a Brachiosaurus it's pretty feeble :-)

There's a circularity in your reasoning, sorry. Given YOUR expectation of what Brachiosaurus looked like, 7 m is feeble. But for what Brachiosaurus might have ACTUALLY looked like, it might have been normal :)


Sorry, Kent, but your composite _is_ an artistic interpretation.

Granted, and we've been here before on the DML (e.g., contributor Scott Hartman) in conjunction with estimate osteological neutral pose (ONP) from steel engravings such as those of Janensch. Some geometric error is invariably introduced in an artist creating a lateral view graphic, including some distortion due to perspective projection (let alone any distortion to the specimen itself). Then there is indeed some further degree of artistic license needed in compositing the individual graphics into a series (e.g., estimating the intervertebral separation and the particular angle between vertebrae in ONP, which necessarily involves some judgement). But I believe both these artistic steps introduce far less error into the interpretation than what can be observed in various artistic reconstructions, including some that have been quite influential.


There's nothing wrong with that, but it [my composite of Janensch's engravings] really doesn't have any more weight that Matthew's or Janensch's or Paul's or Czerkas's or Wedel's.

I doubt you are saying that all those illustrations are equally accurate dimensionally and geometrically. They can't all be right, varying as they do from nearly straight (Czerkas) to raising the neck to near verticality (Paul). I chose to composite the detailed engravings of the individual vertebrae from Janensch. Chris McGowan kindly provided me photographs in lateral view of some of the original material (mostly SI), and except for obvious damage to the specimen from the time they were originally illustrated, there is a rather close correspondence with the individual steel engravings.


But it IS interesting that Janensch's simplified illustration depicting the ascending neck image (the second from right) exhibits more curvature than Janensch's engraving showing the sequence of vertebrae C10-D2, found articulated as a single block. For Janensch's reconstruction to be in ONP and also ascending gracefully, some subtle keystoning was given to the centra at the base of the neck (but not as much of course as Paul provides those same centra).

So which artistic interpretation carries the most weight? I believe Janensch's individual engravings are the most accurate illustrations thus far available, but not his whole skeleton reconstruction (which has other dimensional errors).

And on reflection, I wonder why the Berlin mount, itself a rather liberal "artistic interpretation" with perfectly sculpted neural arches forming a gracefully ascending neck in ONP, was not originally sculpted to accurately match the block from C10-D2 which they had in their possession.

Or, better, just wait until new material with more complete neural
arches becomes available to "lower the boom".

Now that is a strategy worth pursuing :-) If only we could _do_ something about it, though!

Some rather recently found specimens in eastern Utah come to mind :)

OK, but remember those time-honoured expectations got that way because
Matthew and Janensch made it so, and they were not total dummies.

It would be interesting to know what was going through their minds, however, given the pervasive political climate in Berlin at the time, and the associated pressures that must have been palpable among the scientific elite.


Time will tell.

No argument there, anyway :-)

:) Kent