'Unusual' Fossil Footprints Show Evidence Of Injured Dinosaur: Researchers

An odd set of dinosaur footprints discovered in Spain had rather unusual characteristics. It's likely that they belonged to an injured dinosaur, according to a team of researchers.

A fossil trackway is a series of trails left behind by an organism, and they are often great sources of information about the behavior of the extinct animal, the Public Library of Science noted in a news release.

For a new study, published Wednesday in PLOS ONE, a team of researchers took a close look at a rather odd set of dinosaur footprints from the Las Hoyas fossil site in Serranía de Cuenca, Spain.

The trackway is said to be "unmistakenly" that of a large theropod dinosaur and dates back about 129 million years. However, there were two things that were rather "unusual" about the trackways.

For one, although the tracks of the right foot clearly displayed three toes, the left footprints appeared quite "deformed." Another odd trait was that the trackway featured wide steps.

"Our challenge is to understand how and why an abnormally wide bipedal dinosaur trackway with asymmetric footprints could have been produced in the Las Hoyas ecosystem," the researchers wrote.

The researchers adopted a multidisciplinary approach, using various means to examine the trackway. They determined the tracks indeed belonged to a single dinosaur that likely had an injury or deformity on its left foot, and that the wide steps were likely caused by the creature adjusting its gait to compensate for the issue on its left foot.

"All results mutually support the hypothesis that a large theropod dinosaur, with a pathological foot, generated the trackway as it crossed an area of shallow water while slowly walking towards the main water source, thus stepping steadily over the benthonic mat over which multiple fish were swimming," the researchers wrote.

In fact, the right footprints also had deformations, suggesting that the creature was putting more weight on that side. According to the researchers, this shows it persisted to survive even with the setback.

Interestingly, such injuries actually aren't unique to dinosaurs, as even their descendants tend to have them. Poultry and domestic ostriches, for instance, can suffer from "crooked toes" or "curled toes," the researchers said.

"Surprisingly, analogous deformities occur in modern birds despite the astonishing differences in size," the researchers wrote.