🦕 The giant dinosaur that limped and walked in circles

A remarkable paleontological discovery in Colorado reveals a trail of dinosaur footprints forming a perfect loop. Dating back 150 million years, these traces show how one of these giants, a sauropod, moved. Clues left in the rock even indicate the animal may have walked with an asymmetry.


Located near the town of Ouray, this fossilized trackway, nearly 330 feet (100 meters) long, is exceptionally well-preserved. It describes a complete, tight turn before returning to its initial path. Anthony Romilio from the University of Queensland analyzed more than 130 individual footprints that make up this unique path. For this researcher, this configuration provides a rare opportunity to examine the maneuvers of this long-necked colossus, similar to a Diplodocus, which roamed North America in the Late Jurassic.

The research team used drones to capture high-definition aerial images of the entire trackway. This data was then used to build a three-dimensional digital model, enabling precise millimeter-scale analysis in the laboratory. This method revealed details imperceptible in the field.


The digital model allowed the precise retracing of the animal's path, confirming it made a complete loop. Scientists observed changes in the spacing between left and right footprints, shifting from close together to further apart. These adjustments show that step width can change naturally during walking, which could influence the interpretation of short sequences of tracks observed on other trackways.

Another observation concerns step length. Researchers detected a persistent difference of about 4 inches (10 centimeters) between left and right steps. While it is difficult to state with certainty whether this corresponds to a limp or simply a lateral preference, this asymmetry opens new avenues for studying locomotor behaviors from fossilized trackways elsewhere in the world.