Old Vs. New 1
Hi. There used to be a time when I was a far more prolific writer/content creator. With most content now spread on a multitude of third-party social networks and blogs in non-stop decline, why even bother on one? In a nutshell, my reason is Instagram compresses pictures too much to my taste and Twitter threads are a pain in the ass to navigate with and to store them conveniently.
I'm not up for a series of lengthy and deep posts, because neither I have the time to write them (I have other shit to write) nor I want to. What then? One of my great interests has always been classic (and sometimes not so classic) images of dinosaur fossils. Beautiful illustrations and pictures that show the morphology in the most clear way possible to the public.
Despite having some drawing abilities I have developed virtual paleontology far more over the years, since it provides a lot of advantages (faster data collection, higher accuracy/time invested etc). However, I think some figures are just so good in their original conception that I couldn't help but stare in awe at the original fossils once I've been in front of them in a different way from fossils I had not seen depicted in pictures or drawings.
And that has sparked the idea to pay homage to some great figures using the 3D scans I have been doing through the years. Today, I'll start with a comparison of a middle dorsal vertebra of the holotype specimen Camarasaurus grandis from Como Bluff which I got to work with at Yale Peabody Museum in 2017, where it is deposited (YPM 1901).
First, my homage to the classic figure:
And here's the original, drawn by F. Berger for Othniel Charles Marsh, financed by the United States Geological Survey and published by John Ostrom and Jack McIntosh in 1966 (Marsh's Dinosaurs. The Collections from Como Bluff, a must for dinosaur fossil nerds like me):
There is some noticeable differences between them:
The neural spine is taller, and the metapophyses are longer.
The second spinodiapophyseal lamina (SPDL) that unites the diapophyses with the base of the prespinal lamina (PRSL) can't be seen in the 3D model
Centrum, neurocentral suture, diapophyses and metapophyses are more symmetrical in the original figure than the 3D scan of the fossil.
Some can be attributed to perspective, like the relative size of the neural spine and metapophyses. The blurry details on some laminae present in the drawing but not in the scanned model may be a result of 150 years of manipulation and restoration, where additional reconstruction after Marsh's death (something similar happened with the holotype dorsal vertebrae and the referred skull of Brachiosaurus altithorax). However, the extreme symmetry of the vertebra in the reconstruction is clearly a product of retrodeformation, with the artist interpreting the left half of the vertebra as closer to the in vivo condition than the right half.
This last point was one of my biggest surprises. In my mind, this vertebra was pretty much like the drawing, almost completely symmetrical with barely any distortion. However, although the vertebra is pretty nicely preserved next to other sauropods, it is far less symmetrical than the drawing (which was how I expected it to be, even after working with the fossil itself). I guess sometimes an idea creeps into our brain and stays there. This time, thanks to a gorgeous figure.