Australia's Oldest Dinosaur Fossil Identified: 230-Million-Year-Old Footprint in Brisbane

An 18.5-centimeter dinosaur footprint, discovered in 1958 in an Albion, Brisbane quarry, has been formally identified as Australia’s oldest known dinosaur fossil. Dating back approximately 230 million years to the Carnian period of the early Late Triassic, the trace fossil belonged to a sauropodomorph, specifically a prosauropod. This discovery indicates the presence of dinosaurs in Australia significantly earlier than previous records and provides new insight into the continent's early geological history.

Discovery and Preservation

The footprint was found in 1958 by Bruce Runnegar, then a teenager, while exploring Petrie's Quarry in Albion, Brisbane. Runnegar, who later became a palaeontologist, kept the fossil in his personal collection for over six decades, using it as a teaching aid.

Runnegar, who later became a palaeontologist, kept the fossil in his personal collection for over six decades, using it as a teaching aid.

Verification and Identification

In 2021, Professor Runnegar contacted palaeontologist Dr. Anthony Romilio at the University of Queensland for verification. Dr. Romilio utilized advanced photographic and 3D mapping software to analyze the specimen and confirm its authenticity. The research, which included comparisons with other fossilized footprints and skeletal remains found globally, was subsequently published in a scientific journal.

The analysis determined the footprint originated from a sauropodomorph, an ancestral, bipedal dinosaur characterized by a long neck. More specifically, it was identified as a prosauropod, a primitive relative of later long-necked dinosaurs such as brachiosauruses. The dinosaur responsible for the footprint is estimated to have stood 75 to 80 centimeters tall at the hip and weighed approximately 140-144 kilograms, capable of reaching speeds of up to 60 kilometers per hour. Researchers suggest the dinosaur likely left the footprint while walking near a waterway, after which it was preserved in sandstone.

Significance and Context

Dating to approximately 230 million years ago, the footprint is the oldest known dinosaur fossil in Australia, preceding the previous oldest Australian dinosaur footprints found in Ipswich, west of Brisbane, which date back approximately 215 million years.

Dr. Romilio noted its significance as a "puzzle piece" for Australia's early geological history, a period from which dinosaur fossils are scarce on the continent.

The discovery also positions it as potentially one of the oldest dinosaur fossils identified globally.

Donation and Future Prospects

In 2023, Professor Runnegar, now 85, donated the fossil to the Queensland Museum. It has been added to the University of Queensland's collection for ongoing research and educational purposes. Kristen Spring, Senior Collection Manager of Geosciences at the Queensland Museum, emphasized the importance of such additions to Queensland's dinosaur research.

Both Professor Runnegar and Dr. Romilio believe that further dinosaur fossils may exist in the Brisbane area, including within sandstone buildings constructed from material sourced from the same geological formations as Petrie's Quarry. Dr. Romilio suggested that cross-sections in structures like the General Post Office could potentially hold additional palaeontological discoveries.