Preserve and Protect: How Paleontologists Care for Their Long-Dead, High-Maintenance Stars

Fossil collections are where the science of paleontology truly lives. Valuable dino bones must be treated accordingly

The Field Museum's famed T-Rex Sue may be long dead, but she still requires a lot of TLC. Vlad Ghiea / Alamy

How do you take care of a superstar who’s been dead for over 66 million years? That’s a question that William Simpson, the paleontology collections manager at Chicago's Field Museum, faces nearly every day.

Simpson's most high-profile star, Sue, is arguably the most famous Tyrannosaurus rex ever found. The majority of the tryant’s skeleton is reconstructed in the lobby of the Field. But Sue more than a beloved showpiece. This dinosaur is also an essential part of the Field’s scientific collection, where its primary importance is what it can teach us about its long-lost species. Sue's visitors aren’t just the adoring public, but researchers who need to get up close and personal with the predator’s bones to unlock their mysteries.

With that in mind, the Field took great care when putting the dinosaur back together. Sue, Simpson says, “is mounted in such a way that every bone can come off the mount without taking the entire mount apart.” That recently came in handy for researchers. “Just this month we took Sue’s right arm off the mount for high-powered CT scanning at the synchrotron at Argonne National Labs.” That’s not exactly the stereotyped image of what goes on with museum collections.

In the popular imagination, museum collections conjure images of the vast warehouse at the end of Raiders of the Lost Ark, where a lone custodian rolls a precious artefact among row upon row of crates, only to be forgotten. Paleontologists wish that such views would go extinct. “The perception of dark and dusty is a Hollywood cliché,” says Smithsonian National Museum of Natural History curator Hans-Dieter Sues. Museums carefully plan how to care for their specimens—from climate control to pest management—all because these places are where new science is unfolding.

The reality is that collections, on display or tucked away behind the scenes, are places of near-constant activity where paleontologists treat their long-dead charges with care and respect. For instance, the La Brea Tar Pits and Museum. “The fossil collections at La Brea are far from forgotten,” says collections manager Aisling Farrell. “We get visiting researchers from all over the world who come to examine, measure, photograph, and surface scan and document their particular interest." Thousands of fossils have come out of the famous asphalt seeps—from American lion skeletons to specimens as delicate as leafcutter bees still snug in their nest—and these form the basis of a constantly-churning research program, not to mention the fossils that go out on loan to institutions elsewhere.

Simpson of the Field Museum puts it this way: “Our (Vertebrate) Paleo collection, like all the collections at the Field Museum, is a library,” he says, but “instead of books, it consists of vertebrate fossils which represent a vast library of data about the evolution of vertebrates.” All those fossils—from fish to reptiles to dinosaurs to mammals—represent decades of exploration, Simpson says, feeding research at the museum as well as other institutions in the form of over 400 loans to outside researchers. Fossil collections are where the science of paleontology truly lives.

Preserve and Protect: How Paleontologists Care for Their Long-Dead, High-Maintenance Stars
Without exquisite care and organization, fossil collections would be unusable to researchers. Here, modern and fossil herbivore skulls are laid out for comparison at the La Brea Tar Pits' Page Museum in California. MShieldsPhotos / Alamy

Each collection comes with its own challenges. Sometimes it’s a matter of sheer size: The National Museum of Natural History, Sues says, “has the unique challenge of having a wide range of collections totaling over 147 million specimens”—from dinosaurs to preserved plants to cultural artefacts. Further complicating things, the care each specimen requires can vastly differ from one to the next. At La Brea, everything from itty bitty lizard jaws to mammoth bones have to be documented and categorized, each piece tagged with complicated documentation to make sure researchers know exactly where every fossil—large or small—originated. Fortunately, Farrell says, “the fossils are really well preserved, and once the surface has been cleaned with a solvent and dried, they can be stored in drawers for decades.”

Other challenges are common to all collections. Backlogs are a running concern, Simpson says. “When we go out in the field we often collect more specimens than we can process,” he points out. It’s labor-intensive to free fossils of their surrounding rock, catalog them in a database, write catalog numbers of the fossil, make archival labels, photograph them and find a place for them in collections. It may not be as romantic as fieldwork (printing labels doesn’t quite compete with visions of sunburnt paleontologists prospecting desert outcrops for fossils) but it’s essential if those pieces of the past are ever going to teach us anything.

“Just this summer we carried out what we call a ‘Swat Team’ project,” Simpson says. That’s when the Field brings in an outside expert to identify mystery fossils in the collections. In this case, the museum was left with a 50-year-old collection of mammal bones from cave deposits in Australia that hadn’t been fully identified. Paleontologist Bill Turnbull, who had collected the bones, had passed away before the work was done. So the Field put paleomammalogist Matt McDowell to the task and hired five interns to process the fossils identified by McDowell. The end result: 11,098 new fossils cataloged and added to the collections.

All of this is critical for research. A jumble of dusty bones would just be a quagmire. Science relies on carefully-categorized museum collections, which require knowing what a fossil is, where it came from and where to find it in the rows upon rows of other specimens. “Paleontologists make new discoveries in museum collections all the time,” Farrell says, including new species that previously went unrecognized. This past August, Smithsonian researchers announced that they had identified a strange new species of extinct river dolphin hiding within their own collections.

Today there's an even greater push to throw open collections to more people than have ever seen them before. “As part of our collections management in the 21st century, we are actively digitizing our specimens,” Farrell says. "This will eventually mean that research questions, education and engagement are just a click away.” Still, as Sues notes, digitization can only take us so far. For a fossil to be digitized at all, the original specimen has to be carefully and properly cared looked after, forming the core of what a museum is.

Even though many may treat museums as exhibit spaces, the true heart of any museum is in its collections. “Nothing can replace the original evidence for past life when asking questions about the future of life on our planet,” Farrell says. Among the rows of fossils, collections managers, paleontologists and volunteers are working constantly to make sure that rock record has a very long afterlife. Considering fossils as nature’s books, Simpson says: “We best keep the books in our libraries in good shape, so that they can be read now and forever.”

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