Level 1 — Absolute Beginner
Long ago, dinosaurs lived on Earth. One kind was called Edmontosaurus. Another kind was the big meat-eater Tyrannosaurus, or T. rex.
Scientists found an old Edmontosaurus skull in Montana, USA. A broken T. rex tooth is still stuck in its face.
The skull also has 23 other bite marks. This shows a T. rex attacked the Edmontosaurus a long time ago.
Scientists study this skull to learn how T. rex hunted. It is kept at a museum called the Museum of the Rockies.
- dinosaur
- A large animal that lived millions of years ago
- skull
- The bones of the head
- stuck
- Fixed in one place and unable to move
- attack
- To try to hurt someone or something
- bite mark
- A mark left by teeth biting into something
- hunt
- To chase and catch animals for food
- museum
- A building where old and interesting things are kept
- meat-eater
- An animal that eats other animals
Level 2 — Elementary
A fossilized Edmontosaurus skull discovered in Montana's Hell Creek Formation still carries a broken Tyrannosaurus tooth crown embedded in its nasal bone, giving scientists rare direct evidence of an ancient predator attack.
Beyond the embedded tooth, the skull preserves up to 23 additional bite marks left by a tyrannosaur, suggesting the plant-eating Edmontosaurus survived, at least for a time, a violent face-to-face encounter.
The specimen, known by the catalog number MOR 1627, is kept at Montana State University's Museum of the Rockies. It was studied by researchers Taia Wyenberg-Henzler of the University of Alberta and John Scannella of the Museum of the Rockies, and their findings were published in the scientific journal PeerJ.
A new press release from the university has renewed public interest in the fossil, which scientists say offers rare evidence of just how powerful a tyrannosaur's bite could be, and new clues about how the giant predator actually hunted its prey.
- fossilized
- Turned into rock over a very long time, preserving its shape
- embedded
- Fixed firmly and deeply inside something
- nasal bone
- The bone near the nose in an animal's skull
- predator
- An animal that hunts other animals for food
- encounter
- A meeting, often unexpected or unplanned
- specimen
- A single example used for scientific study
- catalog number
- A code used to identify a specific item in a collection
- prey
- An animal hunted by another animal for food
Level 3 — Intermediate
A fossilized Edmontosaurus skull recovered from Montana's Hell Creek Formation retains a broken Tyrannosaurus tooth crown lodged in its nasal bone, a discovery that provides unusually direct physical evidence of a predator-prey encounter roughly 66 million years ago.
In addition to the embedded tooth, the skull bears as many as 23 further bite marks attributable to a tyrannosaur, a pattern that researchers interpret as evidence of a prolonged and forceful attack rather than a single opportunistic strike.
The specimen, catalogued MOR 1627 and housed at Montana State University's Museum of the Rockies, was analyzed by Taia Wyenberg-Henzler of the University of Alberta and John Scannella of the Museum of the Rockies, whose findings appeared in the peer-reviewed journal PeerJ, with the university issuing a fresh press release that reignited broader media attention.
The specimen's significance lies less in confirming that tyrannosaurs preyed on Edmontosaurus, already well established, than in illustrating the sheer force involved: the depth and pattern of the bite marks suggest an incredibly powerful, face-to-face bite, offering paleontologists new insight into tyrannosaur hunting behavior rather than purely scavenging.
- recover (a fossil)
- To excavate and remove a fossil from the ground
- unusually
- In a way that is not common or typical
- attributable
- Able to be traced back to a particular cause
- prolonged
- Continuing for a long time
- opportunistic
- Taking advantage of a chance without much planning
- peer-reviewed
- Checked and approved by other experts before publication
- reignite
- To cause something to start again with new energy
- scavenging
- Feeding on animals already dead, rather than hunting them
Level 4 — Advanced
A fossilized Edmontosaurus skull unearthed in Montana's Hell Creek Formation preserves a broken Tyrannosaurus tooth crown lodged within its nasal bone, yielding an unusually unambiguous physical record of a predator-prey encounter dating to roughly 66 million years ago.
Beyond the embedded crown, the skull registers as many as 23 additional bite marks attributable to a tyrannosaur, a density of trauma that researchers argue points toward a prolonged, forceful assault rather than a single opportunistic strike, complicating any reading of the encounter as a fleeting or glancing interaction.
Catalogued as MOR 1627 and curated at Montana State University's Museum of the Rockies, the specimen was analyzed by Taia Wyenberg-Henzler of the University of Alberta and John Scannella of the Museum of the Rockies, with their peer-reviewed findings appearing in PeerJ; a subsequent university press release has since reignited wider media coverage of the fossil.
The specimen's evidentiary weight lies less in reaffirming an already well-established predator-prey relationship than in quantifying the force behind it: the depth, distribution, and morphology of the bite marks collectively indicate an extraordinarily powerful, face-to-face bite, furnishing paleontologists with rare direct evidence bearing on active tyrannosaur predation rather than the scavenging hypothesis long debated in the literature.
- unambiguous
- Not open to more than one interpretation; completely clear
- trauma (biological)
- Physical injury inflicted on tissue or bone
- assault
- A violent physical attack
- glancing (interaction)
- Brief or superficial, touching only slightly
- curate
- To select, organize, and care for a collection
- evidentiary weight
- The strength or importance of evidence in supporting a conclusion
- morphology
- The form, shape, or structure of something
- hypothesis
- A proposed explanation that can be tested by evidence
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