A High School’s Rock Has One Of Australia’s Richest Dinosaur Footprint Collections

Australia is notoriously lacking in dinosaur bones, and Dr Anthony Romilio of the University of Queensland told IFLScience none have been found on the continent from before the mid-Jurassic. On the other hand, he added, there are many footprints from the earlier part of the dinosaur era, and Romilio has made a career out of studying these.

When Romilio published papers about prints from around Queensland’s Mount Morgan they caused great excitement locally, and some of that spread to nearby areas. Romilio started getting reports that prints were common near Biloela, a neighboring town. After putting out the word he was looking in the area, Romilio received many reports.

Unfortunately, most were unavailable for study. Biloela sits next to a coal seam with multiple mines, and the 200-million-year-old rocks that once sat above it were thick with dinosaur footprints. The mine is open cut, so all those fossils were cleared away to get at the fossil fuel. Undoubtedly many prints, quite likely one of the world’s richest stocks, were dynamited to reach the coal. Some rocks with prints sat at the rim of the mine, however, and were able to be safely removed by the miners.

A few of these rocks were donated to the Queensland Museum and other research institutes, but Romilio said that the miners felt their efforts, or perhaps the rocks themselves, were not sufficiently appreciated by the recipient scientists. 

Consequently, print-bearing rocks have ended up being left in unlikely places, and often forgotten. Romilio found one when visiting a mine. “As I’m driving into the car park, I see one of those car park boulders to stop cars from driving on the lawn,” he said. “And it’s got this clear-as-day dinosaur fossil. My jaw dropped when I saw that.”

The school’s teachers were blown away.

Dr Anthony Romilio

Romilio’s most valuable find had sat for two decades in the foyer of Biloela State High school. The mine’s geologist, Wes Nicholls, was married to a science teacher at the school, and apparently reasoned that if the museum didn’t want it, the school might. Romilio told IFLScience, “The original purpose was for education, Nicholls prepared documentation and worksheets for students. There were instructions on how to measure a print’s size and estimate the hip height of the dinosaur who made them.” Other activities included looking at the shape of the print and working out what the animal may have looked like.

Romilio has not been able to find out how widely used these training materials were, or whether any former students were inspired to a love of palaeontology. To make casts he needed to turn the rock on its side and told IFLScience, “I needed some muscle.” Romilio hired some local plumbers who were former students of the school and had no idea of its significance.

Sad as it is that a teaching opportunity has been wasted, perhaps for 20 years, things may change. Romilio told IFLScience the former students were excited when he explained why he was taking the casts and “the school’s teachers were blown away.”

Romilio and coauthors have found an astonishing 66 dinosaur prints from 47 individuals in an area smaller than a meter squared (10 square feet) on the school rock, as well as a much smaller number on the one from the car park and third survivor of a coal mine.

Casts have been made of each and 3D-scanned. “The photographs and 3D models will be in virtual space forever,” Romilio told IFLScience, just waiting for future scientists to apply new techniques and fresh eyes.

Romilio explained that footprints and bones seldom go together, because the conditions suited to preserving each are very different. Bones and teeth may get the glory, but dinosaur prints are far more abundant. Dinosaurs may not have had health experts telling them to do 10,000 steps a day, but they probably averaged more nevertheless, he noted. “Meanwhile you only have the skeleton you started with.” Even though prints are more easily erase, those starting numbers explain Australia’s Triassic/early Jurassic discrepancy.

On other continents, Romilio said, it’s sometimes possible to match the print to the bone, “Cinderella-like”, but that’s obviously impossible for Romilio, Nicholls and co-authors. “We’re cautious about even saying whether prints come from the one species,” he told IFLScience. “All we can do is make the broadest stroke and identify [the makers] as ornithischian.”

But that doesn’t mean we know nothing. “These dinosaurs were small, with legs ranging from 15–50 centimeters [5.9-19.7 inches] in length and when they left these marks, they were travelling less than 6 kilometers per hour [3.7 miles per hour],” Romilio said in a statement.  “Evidence from skeletal fossils overseas tells us dinosaurs with feet like these were plant eaters with long legs, a chunky body, short arms, and a small head with a beak.”

The study is published open access in Historical Biology.