Imagine stumbling upon a piece of history that rewrites an entire nation’s prehistoric narrative. That’s exactly what happened in Brisbane, Australia, where a fossil discovered over 60 years ago has just been confirmed as the country’s oldest dinosaur fossil—a staggering 230 million years old. But here’s where it gets even more fascinating: this tiny footprint, measuring just 18.5cm, was found by a schoolboy named Bruce Runnegar during a casual visit to Petrie’s Quarry. Little did he know, his discovery would one day become a cornerstone of Australia’s dinosaur history.
Runnegar, now a co-author of the groundbreaking study published in Alcheringa (https://www.tandfonline.com/doi/full/10.1080/03115518.2025.2607630), reflects on the moment: ‘We thought it might be a dinosaur track, but never imagined its national significance. To see it recognized as Australia’s oldest dinosaur fossil is extraordinary.’ This single footprint, preserved in a slab of shale, is the only dinosaur fossil ever found in Queensland’s capital city, making it a truly unique find.
Researchers believe the track was left by an early sauropodomorph—a small, two-legged dinosaur with a long neck. ‘It was likely walking near a waterway when it left the footprint, which was later preserved in sandstone,’ explains Anthony Romilio from the University of Queensland’s Dinosaur Lab (https://dinosaurs.group.uq.edu.au/). ‘That same sandstone was later quarried to build Brisbane’s infrastructure,’ he adds. Based on the footprint’s size, Romilio estimates the dinosaur stood about 78cm tall at the hip, weighed around 144kg, and could sprint at speeds of up to 60 km/hour—a fascinating glimpse into the life of these ancient creatures.
And this is the part most people miss: the original site where the footprint was found is now inaccessible due to urban development. Without Runnegar’s foresight to preserve the slab, Brisbane’s dinosaur history might have remained a mystery. ‘This footprint is the only surviving evidence of dinosaurs from that area,’ Romilio notes.
But let’s pause for a moment—how did this footprint survive for 230 million years? The preservation of dinosaur tracks often involves rapid burial in sediment, which hardens over time, creating a natural mold. For more on this, check out How were dinosaur footprints preserved?.
This discovery raises intriguing questions: How many more dinosaur fossils lie hidden beneath Australia’s cities? And what other secrets might urban development be concealing? Here’s a controversial thought: Could our modern cities be built on top of prehistoric highways, teeming with dinosaur activity? Share your thoughts in the comments—do you think we’ve only scratched the surface of Australia’s dinosaur history?
For more mind-blowing dinosaur stories, explore these:
- Dinosaur hunters make a ‘chilling’ discovery in Canada
- A 100-million-year-old fossil found inside a dinosaur’s belly in the Australian desert
- 16,000 dinosaur footprints discovered in Bolivia—the largest collection ever
Top image: Petrie’s Quarry in Brisbane, 1959. Bruce Runnegar stands in the background alongside fellow students. Credit: Patrick J. Conaghan.
