The mystery surrounding a number of dinosaur footprints on the ceiling of a cave in Australia has been solved after more than 50 years.
There are nine different sets of dino tracks in a cave in central-eastern Queensland that were first discovered back in 1952.
Now, a chance encounter has led one paleontologist to figure out how they got there.
‘The town of Mount Morgan near Rockhampton has hundreds of fossil footprints and has the highest dinosaur track diversity for the entire eastern half of Australia,’ explained Dr. Anthony Romilio from the University of Queensland.
‘Earlier examinations of the ceiling footprints suggested some very curious dinosaur behavior; that a carnivorous theropod walked on all four legs. You don’t assume T. rex used its arms to walk, and we didn’t expect one of its earlier predatory relatives of 200 million years ago did either.’
Researchers wanted to determine if this dinosaur did move using its feet and arms, but found accessing research material was difficult.
‘For a decade the Mount Morgan track site has been closed, and the published 1950s photographs don’t show all the five tracks,’ Dr. Romilio said.
Then he happened to meet a local dentist, Dr. Roslyn Dick, whose father found many dinosaur fossils over the years.
‘Our father was a geologist and reported on the Mount Morgan caves containing the dinosaur tracks in 1954. Besides his published account, he had high-resolution photographs and detailed notebooks, and my sisters and I had kept it all,’ Ms Dick said.
‘We even have his dinosaur footprint plaster cast stored under my sister’s Harry Potter cupboard in Sydney.’
Dr. Romilio said the wealth and condition of ‘dinosaur information’ archived by Ms Dick and her sisters Heather Skinner and Janice Millar was amazing.
‘I’ve digitized the analogue photos and made a virtual 3-D model of the dinosaur footprint, and left the material back to the family’s care,’ he said. ‘In combination with our current understanding of dinosaurs, it told a pretty clear-cut story.’
The team firstly concluded that all five tracks were foot impressions—that none were dinosaur handprints.
Also the splayed toes and moderately long middle digit of the footprints resembled two-legged herbivorous dinosaur tracks, differing from prints made by theropods.
‘Rather than one dinosaur walking on four legs, it seems as though we got two dinosaurs for the price of one—both plant-eaters that walked bipedally along the shore of an ancient lake,’ Dr. Romilio said.
‘The tracks lining the cave-ceiling were not made by dinosaurs hanging up-side-down, instead the dinosaurs walked on the lake sediment and these imprints were covered in sand.
‘In the Mount Morgan caves, the softer lake sediment eroded away and left the harder sandstone in-fills.’
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