Paleontologists Solve a Prehistoric Murder Mystery

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uTypically, when paleontologists dig up dinosaur bones, they have no idea what led to their ultimate demise. But a duck-billed Edmontosaurus fossil recovered from Montana’s Hell Creek Formation in 2005 contained a pretty obvious clue: a sharp tooth buried in the skull.

“Although bite marks on bones are relatively common, finding an embedded tooth is extremely rare,” said Tatiana Wyenberg-Henzler of the University of Alberta, who collaborated with Museum of the Rockies curator John Scannella to publish a study of the discovery in PeerJ this week.

“The benefit of an embedded tooth, especially in a skull, is that it gives you the identity of not only who was bitten, but also who bit them,” she added. “This allowed us to build a picture of what happened to this Edmontosaurus, much like Cretaceous crime scene investigators did.”

They began like any crime scene investigator: with a careful examination of the victim’s body (in this case, a CT scan of the Edmontosaurus skull) and the murder weapon (the tip of the embedded tooth). To identify the culprit, they rounded up the usual suspects – other carnivorous dinosaurs commonly found in the Hell Creek Formation – and compared their teeth to those on the skull. They found a match: Tyrannosaurus.

Read more: “The Spy Who Found T. Rex”

The team determined that the tooth likely came from the middle of the Tyrannosaurus jaw, puncturing the skull with deadly force. The lack of healing around the wound suggests it was likely a fatal shot, although they admit they can’t rule out that a tyrannosaurus lost a tooth while digging.

“A fossil like this is very exciting because it captures behavior: a tyrannosaurus biting the face of this duckbill,” Scannella explained. “The skull shows no signs of healing around the Tyrannosaurus tooth, so it may have already been dead when it was bitten, or it may have died because it was bitten.”

The debate over whether tyrannosaurs were fearsome predators or lowly scavengers has raged for years, but the team points out that most modern carnivores exist along a varied spectrum. Additionally, they cite theories that Tyrannosaurus skull and jaw are specialized for clamping down on the snouts of their prey and choking them, much like wild dogs, a scenario that matches the evidence in this case.

“The way the tooth is embedded in Edmontosaurus’ nose suggests that it met its attacker face to face, which usually happens to an animal killed by a predator,” Wyenberg-Henzler said. “The amount of force required for a tooth to shatter into a bone also indicates the use of deadly force. To me, this paints a terrifying picture of this Edmontosaurus’ final moments.”

We can nevertheless spare a thought for the tyrannosaurus. It’s not like there were prehistoric dentists.

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Main image: PeerJ

• Jake Currie

  Published on February 23, 2026

  Jake Currie is a writer based in Brooklyn, New York.