As It Happens

How a paleontologist and dentist solved the mystery of dinosaur tracks on a cave ceiling

For a long time there was one main theory to explain the strange dinosaur footprints found in an Australian cave. But now, a chance encounter between a paleontologist and a dentist has changed all that.

'As soon as I saw these photographs, it was perfectly clear that the mystery was solved,' says Anthony Romilio

Late geologist Ross Staines measures dinosaur footprints in Australia's Fireclay Caverns in the 1950s. (Submitted by Anthony Romilio)


Anthony Romilio says he has solved a mystery that has puzzled paleontologists for decades — and he owes it all to a chance encounter with a dentist at a produce market.

Like many before him, the paleontologist was curious about the famous dinosaur footprints discovered in 1952 on the roof of the Fireclay Caverns at the Mount Morgan Mine in Queensland, Australia.

First of all, how did the footprints get on the roof of the cave? And equally puzzling — legend had it that they belonged to a carnivorous dinosaur that had been walking on all fours, which, as any dino expert knows, is highly unusual.

Now, with the help of dentist Roslyn Dick, Romilio says he finally has some answers. He believes the prints belong to two bipedal dinosaurs. And the bizarre placement is down to sediment erosion that turned ground into ceiling.

Dinosaur footprints can be seen in the Fireclay Caverns in this photo taken by Staines. (Submitted by Anthony Romilio )

Romilio says he started to piece things together after meeting Dick while he was working at a farmer's market stand.

"I'm selling fruit and veg to her and mentioned that I'm doing paleontology as well," he told As It Happens host Carol Off. 

"She mentions that her dad discovered several dinosaur fossils here in Australia. I had a moment of disbelief — until she said his name, Ross Staines."

Staines was a legendary geologist who found the only Triassic Period dinosaur fossils in Australia. He also was one of the first to study the fossils found at Mount Morgan.

Romilio learned that Dick and her sisters had all of their father's archival material, which included unpublished high-resolution photographs and charts. There was even a dinosaur footprint replica that he made from the Mount Morgan site.

"I felt like a kid at Christmas. I was just so excited with the high quality of all this material," Romilio said.

After looking over Staines' archival material, Romilio concluded that the tracks were actually made by two different sized bipedal dinosaurs.

"Instantly, as soon as I saw these photographs, it was perfectly clear that the mystery was solved. These were not made by a four-legged, quadruped, meat-eating dinosaur," he said. 

He says earlier evidence indicated the footprints were on the ceiling because of the gradual erosion of the layered sediment they were made in.

"The cave footprints were not made by dinosaurs walking on the ceiling," Romilio said. 

"When the dinosaurs were walking on the lakeshore, they left a normal impression into the sediment and then that was covered over by a more resistant sediment — sand, in this case.

"The lake sediment that they walked on became clay stone. The infill became sand stone and the clay stone eroded a lot quicker than the sandstone — so that's why we see it on the ceiling of the caves."

Anthony Romilio, a research associate with the Dinosaur Lab at the University of Queensland, uses a 3D scanner in the field. (Submitted by Anthony Romilio)

The caves were once a popular attraction, but Romilio says they have been closed for a decade due to safety concern. Access to the site is now limited.

"Why this mystery has been hanging for such a long time is that access to the site is quite challenging," Romilio said. "These man-made caves, they're quite large. So from the cave floor to the ceiling can be between four to twelve metres."

Romilio says the extensive Staines archive may hold clues to other mysteries.

"That was really the exciting part, to have something that they had stored in what they called 'the Harry Potter cupboard under the stairs,'" Romilio said. "Here they were showing this to me. I felt amazed with that opportunity."

Since he shared his new theory, Romilio says he has heard from other paleontologists, geologists and hobbyists who are keen to access the material and build on Romilio's work.

"There might be some more historical information that we can provide to glean a clearer picture of what the environment was, what these animals were like," Romilio said.

"It's become a really much larger community involvement in this project, which I think is great."

Written by John McGill. Interview with Anthony Romilio produced by Chloe Shantz-Hilkes.