A school bus-sized dinosaur unearthed in the Egyptian desert has provided the first evidence of contact between African and European dinosaurs shortly before the creatures disappeared for good about 66 million years ago, scientists say.
The plant-eating Cretaceous Period dinosaur, named Mansourasaurus shahinae, was nearly 10 metres long and weighed 5,000 kilograms, researchers said on Monday. It was a member of a group called itanosaurs that included Earth's largest-ever land animals.
Given a dearth of dinosaur skeletons from Africa, palaeontologists have battled to reconstruct a map of how the animals spread across the world after the "supercontinent" Pangaea broke up into different land masses some 200 million years ago.
But then scientists unearthed in a Sahara Desert oasis in Egypt fossils of a long-necked, four-legged dinosaur that lived roughly 80 million years ago.
Previously, many believed Africa's dinosaurs were completely isolated from cousins on other continents by the time their heyday was brought to an abrupt end, possibly by an asteroid strike.
The new specimen, an elephant-sized plant-eater given the name Mansourasaurus, sheds new light on Afro-European dinosaur ties, its discoverers have said.
Looking at its physiology, the research team concluded that Mansourasaurus was "more closely related to dinosaurs from Europe and Asia than it is to those found farther south in Africa or in South America", a statement from Ohio University said.
"This, in turn, shows that at least some dinosaurs could move between Africa and Europe near the end of these animals' reign. Africa's last dinosaurs weren't completely isolated."
Very few dinosaur fossils from the late Cretaceous period, about 100 to 66 million years ago, have been unearthed on the African continent.
Much of the land where fossils may be found is today covered in lush vegetation, unlike the exposed rock in which bones are frequently found in Patagonia, for example.
Mansourasaurus is the most complete dinosaur skeleton from the late Cretaceous ever found in Africa.
The remains include scattered bits of the creature's vertebrae, skull, lower jaw, ribs, and leg bones.
Mansourasaurus is a titanosaur, a group which also included some of the biggest land animals ever to have lived, such as Argentinosaurus, Dreadnoughtus, and Patagotitan.
"When I first saw pics of the fossils, my jaw hit the floor," said study co-author Matt Lamanna of the Carnegie Museum of Natural History.
"This was the holy grail — a well-preserved dinosaur from the end of the Age of Dinosaurs in Africa — that we palaeontologists had been searching for a long, long time."