April 1, 2008
There seems to be some kind of bell curve associated with sauropods. We get lots of medium-sized ones, but very few babies, mostly disarticulated bits, and very few super-immense ones, which are also mostly disarticulated bits. Puertasaurus is known from two vertebrae. Sauroposeidon is known from 3.5. The holotype of Hudiesaurus is a single vertebra; the referred forelimb is not from the same individual or the same quarry, and there’s no particularly good reason to think it’s from the same taxon. Argentinosaurus is known from a handful of vertebrae and a smaller handful of limb bones.
Bruhathkayosaurus was evidently pretty big, but there’s only one paper on it so far, illustrated with very, um, simple line drawings of some bones and blurry non-orthogonal photos of others. More on that one later, maybe, although none of the preserved elements appear to be verts so it is a little outside our bounds. In any case, Bruhathkayosaurus may be the biggest sauropod known from remains that still exist (may be; by now you should know how much uncertainty that covers).
Then there are the really frustrating ones: the gigapods for which we have no remains left at all. What’s really frustrating is that these might be the biggest of all! The best known of our absent friends is Amphicoelias fragillimus, which Darren has discussed before and which we ought to cover here in the future. The genotype of Amphicoelias is the Diplodocus-sized A. altus, and it’s still around, or at least it was as of October 2006 because that’s when I took the photo above. No one knows what happened to the A. fragillimus vert. It might have gotten lost, or simply crumbled to dust since it was very fragile and it was excavated before the use of consolidant glues became widespread in paleontology (Carpenter 2006).
In the case of Aegyptosaurus, we know exactly what happened to the type material: it was blown to hell and gone, along with the original material of Spinosaurus and Carcharodontosaurus, when Allied bombs hit the museum in Munich in 1944. The type material of Aegyptosaurus baharijensis consisted of some caudal vertebrae and limb and girdle bones from an animal of unspectacular size. But in a curious parallel with Amphicoelias, there is–or rather was–a larger specimen, possibly one that represented a distinct species.
Near the end of the paper in which he described and figured A. baharijensis, Stromer (1932a) mentioned “ein Wirbel eines anderen noch größeren sauropod”, which he said would be described later. I’ll end the suspense right now: it wasn’t. Later that year Stromer published a short paper (1932b) on the sauropod fauna of Africa. That paper also did not describe any giant vertebrae in any detail, but it did include this photo (below).
The original caption reads “Professor Ernst Stromer neben einem Wirbel einer neuen Art von Aegyptosaurus“–Professor Ernst Stromer next to a vertebra of a new species of Aegyptosaurus. Presumably Stromer intended to provide a full description soon after, but it was not to be. The next summer at Bahariya Oasis he was attacked by a crocodile and nearly lost his left leg. In the end Stromer recovered, but only after repeated surgeries and many painful months spent learning to walk again. The wound effectively killed his professional career. Although he lived until 1952, his 1934 paper on Bahariasaurus was his last paleontological contribution. Almost all of the Bahariya Oasis collection was lost to science in 1944, but science lost Stromer himself almost a decade earlier.
So what about that vert? It’s clearly a posterior cervical. Stromer’s left hand is resting on the rib, which is awfully short and awfully high up on the centrum, which indicates that the vertebra is from near the base of the neck. There are other interesting features as well–note the hint of a keel on the bottom of the centrum, which is usually only found in fairly basal sauropods, and the ridges above the postzygapophyses, which put me in mind of Mamenchisaurus.
Also, I suppose you’ll have noticed that the vertebra is freakin’ immense. Frustratingly, neither Stromer nor the vert appear in their entirety, and neither are shown from an orthogonal angle (perils of using a portrait to try to do science, I know). Still, we know that Stromer was a tall man. Werner Janensch once playfully described him as “die bärtige Bohnenranke”–the bearded beanstalk. No one seems to have written down his exact height, and we’re missing his feet in this photo anyway, but from contemporary descriptions he seems to have been several inches over 6 feet. The diameter of the cotyle seems to be about the same as the distance between his shoulder and wrist, which is a good 2 feet in me and I’m only 6’2″. Assuming–well, you know–that would give a cotyle diameter of about 60 cm, which is just appallingly large. The cervico-dorsal vertebrae of the HM SII specimen of Brachiosaurus brancai are about 3/4 that big. Imagine B. brancai scaled up by a third.
It’s a cool thought, but that’s all it is. We don’t know exactly how tall Stromer was. We don’t know how much the vertebra might be foreshortened in this photo. It wouldn’t take much to get our imaginary monster sauropod downsized into being merely interesting instead of completely flabbergasting. And the specimen itself is literally history.
Farewell, Aegyptosaurus sp. We hardly knew you.
- Carpenter, K. 2006. Biggest of the big: a critical re-evaluation of the mega-sauropod Amphicoelias fragillimus Cope, 1878. New Mexico Museum of Natural History and Science Bulletin 36, 131-137.
- Stromer, E. 1932a. Ergebnisse der Forschungsreisen Prof. E. Stromers in den Wüsten Ägyptens. II. Wirbeltierreste der Baharîje-Stufe (unterstes Cenoman). 11. Sauropoda. Abhandlungen der Bayerischen Akademie der Wissenschaften Mathematisch-naturwissenschaftliche Abteilung, Neue Folge 10:1-21.
- Stromer, E. 1932b. Die sauropod Fauna Afrikas und seine biogeographical Bedeutung. Monatsberichten der Deutschen Geologischen Gesellschaft 1932:85-91.
Okay, I’m pulling the plug on this one. It’s an April Fool’s Day post. Many of the biographical details about Stromer are just made up–he didn’t lose his leg in a crocodile attack, he did keep publishing after 1934, the giant Aegyptosaurus specimen is a Photoshopped cow vert. The ref for Stromer (1932b) is entirely fake–he never published a paper with that title. The fake paper was “supporting evidence” for the joke, and incorrect biographical details were tells that it was a sham. I’m telling all now because people are starting to look for the real Stromer (1932b), and although the joke had a good run, I hate wasting people’s time.