Bones to Pick
How do you pack up a 68-million-year-old dinosaur for safe storage? Ask Steve Jabo.
Steve Jabo’s biggest project started with a sneeze. A woman was visiting the National Museum of Natural History in the late 1990s with her child, the story goes, and something tickled her nose while they were looking at the dinosaurs. At the very moment she went kerchoo, a chunk of the pelvis fell off the triceratops.
“It totally freaked her out,” recalls Jabo, 53, a vertebrate fossils preparator at the Smithsonian who holds a degree in geology from Pennsylvania State University. “She went right to security.” Soon after, Jabo and his co-workers began assessing the triceratops and other fossils on display. The triceratops, which had been on exhibit since 1904, was in bad shape. “They did their best with whatever they had available” for preparing and mounting in that time period, he says. “But there were lots of cracks in the [neck] frill.”
Jabo spent the next few years working with a team to replace the triceratops bones with bones that they molded and cast with hard plaster and fiberglass cloth, infilled with rigid foam. First, they assembled the skeleton in 3-D on the computer to get the correct pose. Then they made a model out of a special epoxy resin at about one-sixth the size of the real thing—the equivalent of a good-sized dog. Then they re-created it again, at 100 percent, suspending the triceratops from the ceiling and piecing it together, replicated bone by replicated bone. Once they had all of the pieces in place, the dinosaur was moved back to the floor of the museum to face off against the Tyrannosaurus rex. Now, the triceratops is moving again, to become part of a small exhibit while the Paleo/Fossil Hall closes for major renovations.
The closing of the hall—and the renovation of the hall, labs, offices and storage space—doesn’t mean less work for Jabo’s team; it means more work as they pack up the exhibit specimens, assess and conserve some of them to go back in the collections, and remount and repose some of the stars for the 2019 reopening.
On a recent weekday afternoon, Jabo sat at his workstation, using a carbide needle to separate the fossilized remains of a Permian-period lizard from a chunk of rock. That’s just a fraction of his job, which lately has included examining renovation blueprints and curtain designs. He also does fieldwork that lures him far from the Smithsonian, where he’s worked for 25 years, and far from his home in Arlington, where he lives with his wife, Allegra, and daughters, Amelia, 8, and Ella, 10.
What does a fossil preparator do?
I go out in the field and find and collect vertebrate fossils. I bring them back to the museum and remove the surrounding rock or sediment matrix from around the bones to expose the elements needed for study. Then I conserve them and house them, mold them and cast them for distribution or exhibit. There’s also a big public outreach aspect. I go to schools. I go to meetings. And I do lots and lots of volunteer training. [Jabo is also working with a committee to create guidelines and standards for fossil preparation.]
Have you always wanted to work with fossils?
I’ve always loved dinosaurs, but even more I liked working with my hands. I liked building things. So for me, this is the perfect combination.
Do you remember the first time you made an exciting discovery in the field?
I’d been in Wyoming, in the Bighorn Basin, and I uncovered the femur of a sauropod—a diplodocus. I just found this part of it and it kept going and going and going.
Where else have you traveled for fieldwork?
Hell Creek in Montana, and the Judith River formation. The Western interior is really good for fossils. I’ve also been to Eastern Europe. I was in Kazakhstan for a while. Wherever I was able to go, I would go.
How many items do you have on exhibit?
Somewhere around 1,800 to 2,000 specimens, and that’s everything from a tiny shell or trilobite up to the T. rex. [During the renovation] a lot of them will go out for conservation or remounting. The majority haven’t been reposed since they were originally mounted in the 1920s and ’30s. We know more today than we did back then about dinosaur anatomy and posture and how they lived. A lot of these poses have to be changed. We also know more about the chemistry of the bones and better mounting techniques.
Could you give an example of a pose that you’re going to have to change?
The perfect example is the tail dragging of the stegosaurus. They’re always made out to be this big, slow, lumbering thing. But they’re really much more dynamic than that.
How do you move a dinosaur?
In general, we try to get the mount off of an exhibit in as big a chunk as possible; we don’t want to get too tricky and do much fine, detailed work while the dino is in the tighter exhibit spaces. After all of the railings, signs and smaller mounts and specimens are removed from in front of, say, a theropod dinosaur (a meat-eater like T. rex that walks on its rear legs), we first might take off its head and tail and maybe its arms. They are more susceptible to bouncing and vibration because they stick out from the body. The rest of the armature will be tied into the mount’s base and will be more stable. Then we have to get the base freed from the floor or deck that it sits on, which may entail cutting the floor or deck away. The base may already have wheels on it, and the still-standing mount can then be rolled into another section of the hall or building.
Depending on size, we may have to use a forklift to lift the dino and base onto dollies, and then roll it to another section.
How do you decide when to use real bone, versus a cast?
We use a cast when we don’t have the actual bone in the real skeleton and have to fill in, or when the real bone is too fragile. Or when it’s a touchable exhibit. We also use a cast when the bones are part of a holotype specimen—the specimen used to name a new species—and we want to preserve the bones for research behind the scenes. We like to use real bone whenever possible, but we want to conserve these specimens for the long term. We want them to be around for another 200 years so people can really study them. Our first responsibility is to the welfare of each fossil.
When you’re outdoors with your family, are you on the lookout for fossils?
It’s natural now to always be looking around. Your eye develops a detail for picking out things that are a little bit different. I find lots of spare change that way, too.
You also play guitar in a rock band. Is there any link between that and your job besides the fact that you play rock?
The closest overlap is the They Might Be Giants song “I Am a Paleontologist.” We’ve played that a few times. It’s sort of the Paleontologist Theme Song.
Madelyn Rosenberg is a writer in Arlington. Her newest novel, Dream Boy, co-authored with her friend Mary Crockett, comes out in July.