The Skull That Still Has the Tooth In It
Most fossils keep their secrets close. This one is different — it comes with the weapon still stuck in the wound.
On display at the Museum of the Rockies in Montana is a nearly complete skull from an Edmontosaurus, a large duck-billed plant-eater that lived around 66 million years ago. Lodged in the top of its snout is the broken tip of a tooth — and paleontologists have now confirmed it belongs to a Tyrannosaurus rex. The skull also carries 23 separate bite marks. It’s about as close as you can get to a freeze-frame of a real prehistoric attack.
A 66-Million-Year-Old Crime Scene
The skull was dug up back in 2005 in Montana’s Hell Creek Formation — a stretch of rock famous among fossil hunters as one of the best places on Earth to find dinosaurs from the very end of the Cretaceous period, right before the asteroid impact that wiped them out. It sat as a fascinating specimen for years before a new study, published this year in the journal PeerJ by researchers Taia Wyenberg-Henzler and John Scannella, took a much closer look using CT scans (the same 3D X-ray imaging hospitals use, just aimed at rock instead of a patient).
What they found: the tooth tip punched straight through bone into the Edmontosaurus’s nasal cavity, with no sign of healing around it. In living animals, healing shows up as new bone growth around an injury — its total absence here means this bite happened at, or very near, the moment of death. By comparing the serration pattern on the broken tooth to teeth still sitting in known T. rex jaws, the team pinned down not just the species responsible, but roughly its size: an adult with a skull about a metre long.
Hunter, Not Just Scavenger
The bigger question this fossil helps answer is one paleontologists have argued over for decades: was T. rex mainly an active hunter, or mostly a scavenger cashing in on animals that were already dead? The bite marks give a clue. They’re concentrated around the back of the jaw and behind the eye — exactly where the meatiest muscle was on a duck-billed dinosaur. Modern predators eat the richest, most calorie-dense parts of a carcass first and work outward from there. That the skull survived largely intact, while everything fleshier was stripped away, fits a hunter finishing a real meal far better than a passing scavenger picking at leftovers.
That’s what makes a fossil like this genuinely significant, beyond the drama. It’s rare to find direct physical proof — not a guess from bone shape, not a computer model — that ties one specific predator to one specific kill. It reframes T. rex less as the cartoon monster of documentaries and more as a working animal, with a diet, a hunting strategy, and table manners we can actually reconstruct from the evidence it left behind.
It’s also a nice reminder of what makes fossil collecting different from most other collecting hobbies. A fossilized tooth or bone on a shelf isn’t just an old object — it’s a paused moment from an ecosystem that worked much like the ones we still see in nature today. If a genuine dinosaur tooth, ammonite, or other prehistoric piece has ever caught your eye, come have a look at what’s currently on our shelves — every piece has a story like this one hiding in it, even if the full scientific detective work hasn’t been done yet.
Sources:
This dinosaur fossil captures the final moments of a T. rex attack — ScienceDaily
Scientists Found a T. Rex Tooth Embedded in Another Dinosaur’s Skull — ScienceAlert / The Conversation
Wyenberg-Henzler, T.C.A. & Scannella, J.B., “Behavioral implications of an embedded tyrannosaurid tooth and associated tooth marks on an articulated skull of Edmontosaurus from the Hell Creek Formation, Montana,” PeerJ (2026). DOI: 10.7717/peerj.20796
Rare fossil at Montana State’s Museum of the Rockies records Tyrannosaurus attack — Montana State University
