An excerpt from the audiobook My Beloved Brontosaurus, by Brian Switek, read by the author. Used by permission of Macmillan Audio.
Triceratops can be an elusive creature. The 30-foot-long, tri-horned herbivore would have been hard to miss on the Cretaceous landscape, but 66 million years later, what’s left only peeks out of the rock in shards and fragments. When I tried to find this great dinosaur in July of 2010, I didn’t have any luck. As I scuffed around a barren outcrop near Elk Ridge, Wyo.—slightly nauseated from the oil drilling fumes I and the rest of the New Jersey State Museum field crew had inhaled as we passed rig after rig on the way out—I kept looking for some glint of ancient enamel or the spongy texture of broken bone. I found the sunbleached, cracked remains of deer, as well as rabbit jaws that were torn out of their skulls by birds of prey, but no skeletons quite as ancient as I was hoping for.
Triceratops is elusive not only in a physical sense. Paleontologists have been struggling to resurrect the dinosaur as a living animal since the early days of the discipline. The bones haven’t changed since the time our ancestors were little fur balls snuffling around a post–mass extinction world, but our conception of what a Triceratops really is has been changing since before the Yale paleontologist Othniel Charles Marsh even named the dinosaur. There is constant tension between the dinosaurs we used to know and the ones paleontologists continue to tweak and redefine.
In 1887, Colorado school teacher George Cannon discovered two large horns and part of a skull roof in rock near Denver. He sent these bones to Marsh, who thought the remains belonged to an ancient ungulate—Bison alticornis he dubbed the beast—and Marsh changed his mind only after receiving a mostly complete skull of the creature two years later, showing that the “bison” was really a dinosaur. Marsh named it Triceratops horridus, the first step in an attempt to understand the nature of this fantastic animal that continues to this day. Just before I left for Wyoming, in fact, paleontologists John Scannella and Jack Horner proposed a twist in the natural history of Triceratops that spurred intense debate among paleontologists. When the public heard about the proposal (in a form garbled by confused news reports), the response was a howl of anguish. With Triceratops and other classic dinosaurs, the animals researchers know so intimately conflict, sometimes dramatically, with the cherished monsters of our childhood.
I had plenty of time to think over Scannella and Horner’s hypothesis as I hiked over the exposed remnants of Cretaceous floodplains. The scientists suggested that another horned dinosaur found in the same rocks as Triceratops, named Torosaurus, was not a separate genus of dinosaur after all. Instead, it was actually the fully mature form of Triceratops. Late in life, the paleontologists suggested, the flaring frill at the back of the Triceratops skull changed from a solid structure to a more elongated frill perforated by two large holes. The classic image of Triceratops was of an animal that hadn’t fully grown up. Since no one had apparently found a juvenile Torosaurus, and because it’s unusual to find fully mature dinosaurs, this connection could explain the close resemblance of the two dinosaurs and the rarity of Torosaurus.
Marsh named Triceratops in 1889, and two years later he named Torosaurus. According to the arcane rules of taxonomy, this means Triceratops has precedence and the name would not be eliminated; instead, the name Torosaurus would be sunk. Whether that happens depends on whether or not future studies uphold the idea that the dinosaurs belong to the same genus or scuttle it.
Some journalists came to the mistaken conclusion that paleontologists were about to eliminate Triceratops, one of the most beloved dinosaurs of all time! Dinosaur fans were outraged at the news, voicing their discontent in Internet comment threads and on Facebook. (My favorite protest was a mock-up of a T-shirt featuring three Triceratops howling at Pluto, the recently demoted dwarf planet.) Eventually, word went out that Triceratops was safe, but I couldn’t stop thinking about the public reaction as I searched fruitlessly for more dinosaurs in Wyoming. The Triceratops debacle perfectly highlighted the tension between the pop culture dinosaurs we love and the science that is spurring the evolution of dinosaurian visions.
This isn’t the first time paleontology has rocked our relationship with a charismatic dinosaur. Dinosaur expert Elmer Riggs recognized more than a century ago that “Brontosaurus” was not a valid name and that the long-necked, hefty dinosaur should really be called Apatosaurus. For reasons that have never been clear, though, museums and paleontologists continued to use the name Brontosaurus, promoting the image of a dinosaur that never truly existed. No wonder the loss of the great “thunder lizard” still stings. In fact, there’s no better symbol of the constant clash of old and new dinosaurs than that sacred sauropod, which is why the twice-extinct dinosaur became the mascot of my book My Beloved Brontosaurus. From names to the very nature of the animals themselves, new science is pushing the greatest dinosaurian transformation ever seen.