Teacher Discovers 7-Meter Adult T. Rex Trackway in North Dakota, a World First

Q: Could these massive, weathered tracks actually belong to an unknown apex predator instead of a T. rex?

It is possible in theory, but the evidence points much more strongly to an adult *T. rex* than to an unknown predator. The case rests on several factors together, not on size alone. The prints are about 1 meter long, three-toed, and have the narrow toe shape expected of a large tyrannosaur. They come from the Hell Creek Formation, dated to about 66.5 million years ago, where *T. rex* is the best-known giant predator from the fossil record. Researchers also mapped a consecutive 7-meter trackway using high-resolution 3D scans, identifying a consistent left-right walking pattern from the same animal. The main reason for caution is the condition of the tracks. They are heavily weathered, and footprints are trace fossils, not bones. That means scientists cannot assign them with the same certainty as a skeleton. Speed and some fine anatomical details are therefore approximate. Even the team framed *T. rex* as the most likely trackmaker, rather than an absolute identification. Still, an unknown apex predator is not the leading explanation. For that to be more plausible, researchers would need independent evidence that another giant three-toed theropod lived in Hell Creek at that time. So far, the available fossil record does not show a better candidate. In short, paleontologists cannot rule out every alternative, but based on track shape, size, age, and location, *T. rex* remains by far the strongest identification.

3 articles · Updated · IFLScience · Sep 9

Four 1-meter-long footprints found on federal land near Marmarth, North Dakota, form what researchers say is the world’s first adult T. rex trackway, described in the Journal of Vertebrate Paleontology.
The 7-meter trackway dates to 66.5 million years ago, and high-resolution 3D scans indicate two left and two right prints from a large three-toed theropod consistent with an adult Tyrannosaurus rex.
Hell Creek is rich in T. rex fossils but not known for theropod tracks, making the find unusually significant; only two isolated adult T. rex footprints had previously been identified worldwide, in Montana and New Mexico.
Researchers estimate the animal had a 4-meter stride, hips about 4 meters high, and was likely walking at roughly 1.5 to 2 meters per second, though the tracks reveal little about finer gait details.
The discovery was made in 2025 by Northglenn High School teacher Kent M. Hups, now a co-author, underscoring how rare trackways can capture dinosaur behavior that bones alone cannot.