Thanks to the museum’s dramatic displays, many of us can imagine Triceratops with its horns and sprawling neck shoulder to fend off a hungry Tyrannosaurus rex. But some scientists believe that Triceratops used their deadly head coverings against each other as well. Like a duel of elk waving its horns, Triceratops may have intertwined its horns to attract mates or defeat rivals.
While scientists have long speculated about such behavior, conclusive evidence for these clashes has proven elusive. But in a study published Thursday in Scientific Reports, a team of Italian scientists described what they believe is a hiatus scar from one of these ancient battlegrounds on the frill of the neck of a high-profile Triceratops known as “Big John.”
Discovered by commercial fossil hunters at work on the cliffside of South Dakota in 2014 and named after the farmer who owned the land, Big John received little buzz until an Italian fossil preparation company purchased and recovered dinosaur remains in 2020. As the largest triceratops specimen ever discovered ( The skull alone is more than five feet long), and Big John was sold to an anonymous bidder last October for $7.7 million—the highest price ever for a fossil other than a Tyrannosaurus rex.
In addition to its impressive size and price, the creature’s skull has a large crescent-shaped hole at the base of its neck. While many triceratops skulls bear similar foramina, few have been studied in depth according to Ruggero D’Anastasio, a paleopathologist at D’Annunzio University in Chieti Pescara in Italy and author of the study.
There has long been a debate about the causes of these vacuoles in the cilium of Triceratops. Some believe they are scars from interspecies conflicts or close encounters with predators. Others believe they may be signs of infectious disease or possible age-related bone breakdown. In Big John’s case, the bone around the gap is coated in coarse plaque-like deposits, a sign that the area was once inflamed.
But to determine whether the inflammation was from disease or traumatic injury, the researchers had to dig deeper. They examined bone tissue samples from around the gap in microscopic detail, looking for telltale signs of bone healing and remodeling.
By examining the samples under an electron microscope, the team noted that the bone closest to the hole was more porous and full of blood vessels than the bone distal, indicating that the hole was surrounded by newly formed bone. They also identified the tiny pits that typically occur when bone is remodeled by specialized cells called osteoclasts.
All of these signs point to a triceratops on the mend. “The stages of bone healing are similar to those observed in mammals, including humans,” said Dr. Danastasio. “We certainly are facing a traumatic injury that did not cause the death of Triceratops.”
Researchers believe the keyhole-shaped hole was pierced into Big John’s frill by another Triceratops horn. The unique location of the wound prompted the researchers to assume that the frill had been punctured from behind.
Whatever Big John stabbed, the team estimates that the dinosaur survived another six months based on bone healing. When the lumbering dinosaur died, about 66 million years ago, it was buried in sediments in the Hill Creek Formation, a hotbed of fossils deposited at the end of the dinosaur era.
The Big John specimen is among a growing list of enormous dinosaur fossils that go for exorbitant amounts of money for private buyers. These staggering sums bode well for public museums and universities, and create barriers between exquisitely preserved specimens and paleontologists.
With Big John, for example, the bone tissue samples analyzed in the new study are stored in the Kitty University Museum’s collection, but the whereabouts of the larger skeleton is still unknown. This hinders paleontologists’ ability to thoroughly examine the new finds, according to Denver Fowler, curator of the Badlands Dinosaur Museum in North Dakota. “No one can actually go see this diseased area for themselves,” he said. “Repetition is the bottom line of science.”
These concerns have led the Society of Vertebrate Paleontology to discourage researchers from studying privately owned fossils.
Dr. Fowler believes that even if only a fraction of the money and attention spent on Big John were dedicated to paleontologists, it would help them discover, prepare and study the most scientifically important Triceratops fossils.
He said, “I expect that many museums have unprepared specimens of better quality and greater importance than Big John, but the lack of resources leaves these specimens in their field jackets.”