Scientists have uncovered the oldest known cerapodan dinosaur fossil, dating back 168 million years. A team from the Natural History Museum and the University of Birmingham in the UK and Morocco’s Sidi Mohamed Ben Abdellah University discovered the fossil in the Middle Atlas Mountains in northern Morocco.
The fossilized thigh bone, identified as belonging to a plant-eating cerapodan dinosaur, was found in the El Mers III Formation, a site already known for producing the world’s oldest ankylosaur fossil. The study’s results were published in the journal Royal Society Open Science. Scientists believe this new find provides crucial evidence for understanding the evolution of this group of dinosaurs.
Cerapodan dinosaurs were similar to modern birds
Cerapodan dinosaurs were small, herbivorous creatures that moved on two legs, similar to modern birds. They belonged to the “Ornithischian”, or “bird-hipped,” dinosaur group. These dinosaurs were widespread during the Cretaceous period, but their early history remains largely unknown due to a lack of fossils from the Middle Jurassic era.
Previously, most evidence of their existence came from fossilized footprints rather than skeletal remains. The newly discovered femur, however, gives paleontologists a rare glimpse into their early development. Researchers identified it by its distinct shape and groove on the upper back portion of the bone, features unique to cerapodan dinosaurs.
This fossil predates what had previously been the oldest known cerapodan fossil, found in England, by two million years. Its discovery helps fill gaps in the timeline of dinosaur evolution, offering fresh insights into how these creatures adapted and diversified long before the Cretaceous period.
Fossil found in Bathonian rock layers
The fossil was found in Bathonian rock layers, dating to the Middle Jurassic. This suggests that cerapodan dinosaurs had already started evolving into different species long before they became common in the fossil record. Their ability to adapt to various environments may have contributed to their long-term survival.
Paleontologists have long theorized that these dinosaurs existed before the Cretaceous, but the lack of fossilized bones made it difficult to confirm. This find strengthens the idea that cerapodans were already diversifying in different ecosystems long before their dominance in later periods.
The discovery raises the possibility that more cerapodan fossils may be buried in Morocco’s Middle Atlas Mountains. Researchers plan to continue excavations in the area, hoping to uncover additional remains that could further explain the early development of this dinosaur group.
This fossil provides a key link in understanding how plant-eating dinosaurs evolved and spread across the globe. With further research, scientists may soon unlock even more details about life during the Middle Jurassic, which remains one of the least understood chapters in dinosaur history.