First duckbill dinosaur fossil discovered in Africa

Duck-bill dinosaurs evolved in North America and spread to South America, Asia, Europe, and eventually Africa. Photo credit: Raul Martin

The first fossils of a duck-billed dinosaur were discovered in Africa, suggesting that dinosaurs crossed hundreds of kilometers of open water to get there.

The study, published in chalk Research, reports the new dinosaur, Ajnabia odysseus, from rocks in Morocco to the end of the Cretaceous 66 million years ago. Ajnabia was a member of the duck-billed dinosaurs, various herbivorous dinosaurs that grew up to 15 meters long. But the new dinosaur was tiny compared to its relatives – only ten feet long, it was the size of a pony.

Duckbills developed in North America and eventually spread to South America, Asia, and Europe. Since Africa was an island continent in the Late Cretaceous Period, isolated by deep-sea routes, it seemed impossible for duckbills to get there.

The discovery of the new fossil in a mine a few hours from Casablanca was “the last thing you would expect in the world,” said Dr. Nicholas Longrich of the Milner Center for Evolution at the University of Bath, who led the study. Dr. Longrich said, “It was completely out of place, like finding a kangaroo in Scotland. Africa was completely isolated from the water – how did you get there? ”

The silhouette shows the size of Ajnabia compared to humans and the contemporary Maastricht dinosaur fauna of Morocco. Photo credit: Dr. Nick Longrich

Study of AjnabiaThe characteristic teeth and jawbones indicate that it belonged to Lambeosaurinae, a subfamily of duckbills with ornate bony head crests. Lambeosaurs evolved in North America before spreading to Asia and Europe, but were never found in Africa.

They reconstructed the development of duckbills and found that the lambeosaurs evolved in North America and then spread to Asia via a land bridge. From there they colonized Europe and eventually Africa.

Because Africa was isolated by deep oceans at that time, duckbills must have rafted hundreds of kilometers on rubble, swim, or swim to colonize the continent. Duckbills were likely powerful swimmers – they had large tails and strong legs, and are often found in river debris and ocean rocks, so they may have simply swum the distance.

“Sherlock Holmes said that once you did away with the impossible, anything that is improbable must be the truth,” said Longrich. “It was impossible to go to Africa. These dinosaurs evolved long after the continental drift separated from the continents, and we have no evidence of land bridges. Geology tells us that Africa has been isolated from the oceans. If so, the only way to get there is by water. ”

In relation to this feat the dinosaur is called “Ajnabia odysseus.Ajnabi is Arabic for “foreigner” and Odysseus refers to the Greek navigator.

Map showing the location of the duckbill dinosaurs during the Late Cretaceous Period. Photo credit: Dr. Nick Longrich

Ocean crossings are rare, unlikely occurrences, but have been observed in historical times. In one case, green iguanas traveled on rubble between Caribbean islands during a hurricane. In another case, a turtle from the Seychelles flew hundreds of kilometers across the Indian Ocean to wash off in Africa.

“Over millions of years,” said Longrich, “events will likely happen many times in a century.” Ocean crossings are required to explain how lemurs and hippos came to Madagascar, or how monkeys and rodents got from Africa to South America. ”

The fact that duckbills and other groups of dinosaurs spread between continents even when sea levels are high suggests that dinosaurs also traveled across oceans. “As far as I know, we are the first to suggest crossing the ocean,” said Longrich.

The international team of scientists was drawn from the University of Bath with researchers from the University of the Basque Country UVP / EHU (Spain), George Washington University (USA) and the Natural History Museum of Sorbonne University (France) / Universite Cadi Ayyad (Morocco).

Dr. Nour-Eddine Jalil from the Natural History Museum of the University of Sorbonne (France) said: “The sequence of unlikely events (crossing of an ocean by a dinosaur, fossilization of a land animal in a marine environment) underscores the rarity of our find and thus its importance.

„„Ajnabia shows us that hadrosaurs have entered African land and that ocean barriers are not always an insurmountable obstacle. ”

Reference: “The first duck-billed dinosaur (Hadrosauridae: Lambeosaurinae) from Africa and the role of oceanic expansion in dinosaur biogeography” by Nicholas R. Longrich, Xabier Pereda Suberbiola, R. Alexander Pyron and Nour-Eddine Jalil, November 2nd 2020, Chalk research.
DOI: 10.1016 / j.cretres.2020.104678