June 15, 2008
Paul Sereno’s Project Exploration has a traveling exhibit called The Science of SuperCroc, which I recently visited at my old stomping grounds, the Oklahoma Museum of Natural History. The exhibit focuses on Sarcosuchus, the improbably large and possibly Kryptonian crocodilian from the Cretaceous of Niger, but it also includes nice mounted skeletons of the spinosaur Suchomimus and–relevant to our purposes here–the just plain improbable sauropod Nigersaurus.
At least one of my co-bloggers probably thinks I should stop pandering to the crowds with my mounted skeleton posts and get back to hardcore vertebral anatomy. After all, that’s the raison d’etre of SV-POW!, and I have been falling behind a little lately. Still, I’m going to risk the Wrath of Mike and go ahead and post about the mounted Nigersaurus skeleton, and why you should definitely go see it if you get the chance.
Here are my reasons for doing so:
1. It is a demonstrated scientific fact, as rock-solid as the value of c or the proposition that the Amazon basin is damp, that Nigersaurus is Damn Weird. In a clade of little-known weirdos (Rebbachisauridae), it promises to be an exceedingly well-known ultra-weirdo, thanks to (1) the large number of skeletons that have been discovered, including both juveniles and adults, and (2) the sheer vastness of its weirdness, which you can sample immediately and without charge courtesy of Sereno et al. (2007) and the kind offices of the Public Library of Science (translation: free paper here).
2. Although Nigersaurus was named in 1999 and has been the subject of three peer-reviewed publications, not much of the skeleton has been figured to date. So the opportunity to see the whole critter up close is pretty remarkable. If sauropods were heavy metal, the traveling Nigersaurus mount would be an evening backstage getting high with Led Zeppelin, circa 1973. Certainly if you work on sauropods, the morphology of Nigersaurus will make you think that someone has been under the influence of powerful illicit substances, and that someone is Mother Nature (or Gaia, or the overused/sexist/quasi-pantheistic biosphere personification of your choice).
3. It’s a really nice mount. It’s fiberglass, but the quality of the casts is first rate. I have seen a lot of traveling skeletons that looked like they were made out of Play-Doh by speed-sculpting chimps, but the mounts in the SuperCroc exhibit are all well cast, gracefully mounted, and nicely displayed, by which I mean that you can get up close to them and walk most or all of the way around them, which is my major pet peeve about mounted skeletons: I want to be able to see them from any angle, or at least many angles. SuperCroc delivers.
4. The exhibit includes a lot of display cases that explain the detailed anatomy of the beasts. For Nigersaurus alone, there were cases on vertebral pneumaticity (yay!), the vertebrae themselves (real bones), the detailed anatomy of the jaws (real bones, from the holotype!), the head and neck skeleton plus life sculpture (shown at the top), adult and baby femora (real bones), probable feeding ecology, and maybe one or two others I can’t remember, plus a giant wall hanging of the full-color life restoration painting that came out with the 2007 paper.
So if you get a chance to see SuperCroc, it’s worth it just for the sauropod.
I’ll have tons more to say about the Nigersaurus vertebrae in future posts, but the short version is that they are small and unbelievably delicate. Mike and I always characterize Camarasaurus vertebrae as coarse, fat, and kind of ugly; the vertebrae of Nigersaurus are the aesthetic opposite. They look like they might have been constructed out of toothpicks and white glue. And they are crazy pneumatic. In one of his essays, outdoor humorist Patrick F. McManus characterized a poorly-maintained country bridge as consisting mostly of holes that were elevated and loosely defined by a few rotting beams. Similarly, the skull and cervical vertebrae of Nigersaurus seem to be mostly holes, with just enough bone around them to suggest the form of a sauropod. One more half-baked comparison: the mounted Nigersaurus looks like the skeleton of a skeleton, at least in the craniocervical region.
I want to make a final point that is not really about vertebrae. As you can see in the photo above, and to beat a dead thunder-lizard, sauropods had erect limbs, compact feet, and deep, slab-sided bodies. You don’t have to be a zoologist to see that this is a body-form made for roaming the land, not for bobbing around slurping up pond scum. That’s not to say that sauropods didn’t go into the water. They probably did so all the time. Elephants do, almost every chance they get. Heck, elephants may even be descended from aquatic ancestors. But no one would characterize elephants as aquatic or even semi-aquatic. Sauropods weren’t elephants, and they weren’t giraffes, and facile comparisons of sauropods to big mammals have probably done more harm than good to sauropod paleobiology. But sauropods weren’t hippos or manatees, either, despite decades of ecological characterization as such. The Aquatic Sauropod era officially ended the same year I was born, so you may rightly wonder why I am tilting at this particular windmill. It’s because ideas are seductive, and sometimes we allow them to make us blind to the obvious. I don’t know of any way to fight that tendency other than to keep asking questions.
And I don’t know of a sauropod that is more likely to provoke questions than Nigersaurus. Go see it if you can.