The implication: Tanzania's "oldest dinosaur" fossils may be younger than researchers assumed, and the geography of dinosaur origins may need rethinking.

Lead author Hady George, a PhD student in Bristol's School of Earth Sciences, said: "Our discovery marks the first confirmed record of the genus Dinodontosaurus outside South America. The finding links the Tanzanian and South American fossil-bearing rocks, showing they are of equivalent age."

George added: "This helps confirm that the oldest dinosaur candidates from Tanzania are probably no older than those from South America, refining the timeline of dinosaur origins."

Why did it take decades to publish?

Paleontologist Nigel Larkin first studied the dicynodont skeleton in 1994 for his MSc thesis at University College London. He suspected then that it represented a new species.

"I studied this dicynodont skeleton for my MSc thesis at University College London back in 1994 and judged it to be a species new to science, but it took me nearly 30 years to start the process of writing it up for publication," said Larkin, now a Visiting Research Fellow at the University of Reading. "I'm glad I waited, as the international team we put together, headed by Hady George, has done an amazing job of fleshing-out this story in much more detail and depth than I could have achieved on my own."

Larkin also pointed to dramatic improvements in tools and collaboration. "Techniques have improved vastly over the last 30 years too — we can do so much more with micro-CT scanning, etc. to examine such specimens than we ever could have imagined in the 1990s, and international collaboration is so much easier. And what's 30 years? It's the blink of an eye compared to the age of this prehistoric specimen."

What can museum collections still reveal?

The researchers stressed that old specimens can still transform science. Dr. Mike Day, Curator of Non-Mammalian Tetrapods at the Natural History Museum, London, noted the specimen had been in the museum's care for more than 60 years.

"This fossil specimen from Tanzania has been in our care for over 60 years, and it's wonderful that its identity has now been brought to light," Day said. "By revealing that Dinodontosaurus lived in South America and eastern Africa, it offers a glimpse of our planet 240 million years ago."

"It goes to show how revisiting museum collections can change our understanding of the past just as much as finding new fossils in the field, showing the importance of looking after these invaluable records of life on Earth," Day added.

What's next?

A large share of the Tanzanian Dinodontosaurus material remains unstudied, especially postcranial bones — those from the body excluding the skull. The team plans to:

• Compare those remains with South American Dinodontosaurus fossils
• Investigate the biomechanics of dicynodonts and related species
• Examine how several large plant-eaters coexisted in Triassic ecosystems

The findings are preliminary and based on a small sample of remains, but they offer one of the clearest cross-continental tie points for dating early dinosaur-bearing rocks. Forthcoming research projects will revisit the remaining material and explore the ecology of Triassic dicynodonts in greater detail.