The Cretaceous Shuffle

After almost two decades as the Field Museum's crown jewel, Sue the T-Rex is being relocated to the museum's Evolving Planet exhibit to make way for a larger dinosaur specimen.
After almost two decades as the Field Museum's crown jewel, Sue the T-Rex is being relocated to the museum's Evolving Planet exhibit to make way for a larger dinosaur specimen.

After 17 years front-and-center, the Field Museum’s toothy crown jewel Sue is moving upstairs to make way for an even larger predator.

By Adam Cohen
Medill Reports

Almost 67 million years after her death, the world’s most famous dinosaur named Sue is moving once again. In February, the Field Museum’s iconic Tyrannosaurus rex will be taken down from her prominent perch in Stanley Field Hall and moved to a new exhibit on the institution’s second floor. In Sue’s place will go an arguably even more awe-inspiring specimen – a cast of Patagotitan mayorum.

Patagotitan was unearthed in Argentina in 2014 and, at 122 feet long, is the world’s largest dinosaur. But he will have his work cut out for him if wants to win over the hearts of Chicagoans the way Sue has since she was put on display almost two decades ago. As Sue prepares for her march upstairs, here are five fun facts about our beloved Cretaceous creature.

1) She’s one of a kind.
Sue’s 40-foot-long frame stands out in many ways. “She’s the largest, most well-preserved T. rex ever found,” says Mihir Patel, a docent at the Field. “And the most complete, by far, by volume. Ninety percent of Sue is real.”

The fact that she is even on exhibit is also an anomaly – the museum has room to display only one-half of 1 percent of its vast research collection of vertebrate fossils.

2) She might not even be a “she.”
Sue’s real name is FMNH PR 2081, which admittedly would look terrible on a gift shop T-shirt. She was given her nickname to honor Susan Hendrickson, the paleontologist who discovered the fossils in 1990 while working for a private excavation company, called the Black Hills Institute, on the Cheyenne River Indian Reservation in South Dakota.

But we actually can’t be sure whether Sue was male or female. “There aren’t enough T. rexes to get enough information from both and figure it out,” Patel says.

3) She’s the Field’s most expensive acquisition.
In fact, Sue is one of the Field’s only acquisitions – the museum’s fossils are collected mostly by its own scientists. A legal battle and ensuing auction following Sue’s discovery led the museum to make an exception and bid on the unique specimen.

The Black Hills Institute claimed the fossils belonged to them, as they had paid a nominal fee to Maurice Williams, the owner of the land, for the rights to excavate them. Williams is a Sioux (what delightful homophony!) Native American, and the tribe argued that the bones were theirs. For his part, Williams claimed that he had agreed to allow the corporation only to exhume the skeleton, not to sell it. In 1995, the court ruled in favor of Williams, and he signed a contract with Sotheby’s to auction the dinosaur.

Concerned that the paleontological prize would fall into private hands, the Field Museum, with the help of a number of donor institutions, purchased Sue for roughly $8 million. “I’m very happy that the Field Museum got it, and not some rich billionaire somewhere that would hide her away,” Patel says.

4) She’s cleaned twice each year.
It’s quite a sight to see: Bill Simpson, the Field’s head of collections, circling the dinosaur in a construction lift, removing chunks of dust with a blower and feather duster. Simpson was the chief preparator when the museum obtained Sue, and thus knows the bones better than anyone else in the world.

There are some stains that Simpson isn’t able to get to during his routine cleanings, though. Most notably: bird poop. “Every now and then, we’ll get a bird in this huge room,” Simpson says. “It’s 300 feet long, with 70-foot ceilings. So it can become quite the aviary.”

When Sue is taken down in February, she will undergo a process called “condition reporting” before being remounted in her new exhibit. Simpson and his team will photograph every one of her bones to see which spots require a deeper scrub. “One of the many lovable things about Sue is that the bone is extremely well preserved,” Simpson says. “So you can do gentle cleaning with water. That’s how we’ll clean off the bird poop.”

5) She has been on display in Stanley Field Hall temporarily – for 17 years.
The Field moved from the building that now houses the Museum of Science and Industry to its current home in Grant Park in 1920. The building contains six courtyards, which were designed to allow light and air into the exhibit halls. Over time, as the museum’s collections grew, these spaces were filled in with displays. When the museum acquired Sue in 1997, the plan was to mount her in the northeast corner of the building, in the last vacant light well. But the exhibit wasn’t ready in time, so in May 2000, Sue was given her temporary placement in the main hall.

When she comes back on display in late spring 2019, Sue will be incorporated into the Evolving Planet exhibit that now occupies what was to be the skeleton’s original home. “When we put her in her own hall, we can have other fossils that were found along with Sue, and we can have some of the dinosaurs that she preyed on,” Simpson says. “She’s a wonderful icon here, but we’d like to tell more of the scientific story.”

Photo at top: After almost two decades as the Field Museum’s crown jewel, Sue the T-Rex is being relocated to the museum’s Evolving Planet exhibit to make way for a larger dinosaur specimen. (Photo by Adam Cohen/MEDILL)