I grew up in Chaozhou, a small city in southern China surrounded by mountains and sea. I was always fond of dinosaurs, and when I was in high school I set up the first website dedicated to dinosaurs in China.
Now, as a professor at the China University of Geosciences in Beijing, I’m also active on social media, with more than 6.2 million followers on [the microblogging website] Weibo, where I share updates on my research into dinosaur fossils and footprints.
On 11 July this year, I received a Weibo message from a designer called Ou Hongtao. He had been dining in the courtyard of a restaurant in Leshan, a city in southern Sichuan famous for its ancient mountains, and noticed oval pits in the stone floor. He sent me a photo – they were regular in size, and in a row. He had learned about dinosaur footprints from my blog and wanted to know my opinion.
I first told Ou to send me a few more photos then decided to book a ticket to fly to Leshan to see the pits in person. I contacted the restaurant owner, a garden designer named Zhu Min, and asked if we could investigate.
She told me that the courtyard was used by the previous owners to raise chickens, and the pits may have been the result of the sheds that were previously erected there. The new stone floor was dug up by the restaurant only last year – before it had been covered in cement. My heart sank. But I had to see it for myself.
As I approached the restaurant with my research team, driving along a very unremarkable road, we noticed more ferns, bringing to mind the era of the dinosaurs. Zhu and Ou came to meet us there.
I went straight to the courtyard and carefully approached these pits. The stone ground was mossy and slippery: I had to take care not to fall. We were surrounded by large banana trees, a spring and a miniature lotus pond next to a red rock wall full of moss.
At first, the pits looked like ordinary ones you would find on the side of the road, the kind you usually wouldn’t look at twice. Zhu looked at me as if I was about to do a magic trick.
I took two laps around the yard. After careful consideration, I knew they were dinosaur footprints. They were regular, and formed two columns – for the left and right feet. The pits had two different shapes, one for the front feet and the other for the back feet. No natural factors could result in such a coincidence.
On the other side of the yard, I found another set of tracks, though not as well preserved. I’ve studied dinosaur footprints for a long time and can survey prints from above, making out who they belonged to, how they walked and the pattern of the trail.
We had discovered typical Brontopodus-type tracks, belonging to those large plant-eating dinosaurs with long necks and tails. I imagined there were at least two dinosaurs walking by the water. Perhaps one of them sped up a bit. Zhu was very surprised. “Now,” she said, “it really looks like a dinosaur had walked by!”
The “cement covering” Zhu had mentioned was in fact a mixture of lime, clay and fine sand that the previous owner used to pave over the stone ground. He hated the rocks, and wanted a surface that allowed his chickens to walk easily. When Zhu took over the restaurant, she wanted to play with the idea of natural beauty, and so removed this upper layer, revealing the footprints.
All the mysteries were solved and I relaxed. My team carefully studied and measured the footprints. Ou felt very proud, especially when I told him that amateurs can make great contributions to dinosaur studies.
This was the first time that dinosaur footprints have been found in downtown Leshan. This is a magical land. Footprints from the smallest dinosaur in the world – the Minisauripus, measuring from 1cm to 3cm – have been found in rural Leshan as well as South Korea. There have also been prints found deep in a cave from the Tang dynasty in Sichuan province.
I told Ou to continue to search for dinosaur footprints, and asked Zhu to protect the footprints in her restaurant. I hope they will become a landmark, so the children of the city will know dinosaurs once walked through their back yards.
• As told to Vincent Ni and Xiaoqian Zhu
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