In a quiet corner of the Museum of the Rockies in Bozeman, Montana, a specimen collected more than two decades ago has offered fresh insight into behaviour from the Late Cretaceous. The skull, known as MOR 1627, belonged to an edmontosaurus. Embedded within its nasal bone sits a broken tooth from a tyrannosaurus.
Researchers examined the fossil using modern techniques including CT scans. Their work, published in the journal PeerJ on 12 February 2026, records the tooth penetrating the left nasal at an oblique angle. No signs of healing appear in the surrounding bone. Up to 23 additional tyrannosaur bite marks mark the skull.
The skull shows no signs of healing around the tyrannosaur tooth, so it may have already been dead when it was bitten, or it may be dead because it was bitten.
Taia Wyenberg-Henzler, doctoral researcher at the University of Alberta, offered that assessment in the Montana State University press release issued on 14 July 2026. The absence of reactive bone growth indicates the injury happened at or near the time of death. Such physical evidence stands as a rare window into events from roughly 66 million years ago.
A face-to-face encounter
The orientation of the embedded tooth suggests the edmontosaurus met its attacker directly. Wyenberg-Henzler noted the implications.
