School bus-sized dinosaur found in Egyptian Sahara

Scientists have unearthed fossils of a long-necked, school bus-sized dinosaur in the Sahara Desert of Egypt that lived about 80 million years ago, a discovery that sheds light on dinosaur evolution in Africa.

The fossilised remains of the dinosaur species named Mansourasaurus shahinae were unearthed by an expedition undertaken by a team at the Mansoura University in Egypt.

"Mansourasaurus shahinae is a key new dinosaur species, and a critical discovery for Egyptian and African paleontology," said Eric Gorscak from The Field Museum in the US.

Mansourasaurus belongs to the Titanosauria, a group of sauropods (long-necked plant-eating dinosaurs) that were common throughout much of the world during the Cretaceous, period from 100 to 66 million years ago, researchers said.

Mansourasaurus, however, was moderate-sized for a titanosaur, roughly the weight of an African bull elephant, according to Hesham Sallam, lead author of the study published in the journal Nature Ecology and Evolution.

Its skeleton is important in being the most complete dinosaur specimen so far discovered from the end of the Cretaceous in Africa, preserving parts of the skull, the lower jaw, neck and back vertebrae, ribs, most of the shoulder and forelimb, part of the hind foot, and pieces of dermal plates.

"Africa remains a giant question mark in terms of land- dwelling animals at the end of the Age of Dinosaurs," said Gorscak, who began work on the project as a doctoral student at Ohio University in the US.

"Mansourasaurus helps us address longstanding questions about Africa's fossil record and paleobiology - what animals were living there, and to what other species were these animals most closely related?" he said.

The lack of fossil record from Late Cretaceous in Africa is frustrating for paleontologists since, at that time, the continents were undergoing massive geological and geographic changes.

That means that the course of dinosaur evolution in Africa has largely remained a mystery, researchers said.

Historically, it has not been clear how well-connected Africa was to other Southern Hemisphere landmasses and Europe during this time - to what degree Africa's animals may have been cut off from their neighbours and evolving on their own separate tracks.

Mansourasaurus, as one of the few African dinosaurs known from this time period, helps to answer that question, researchers said.

By analysing features of its bones, the team determined that Mansourasaurus is more closely related to dinosaurs from Europe and Asia than it is to those found farther south in Africa or in South America.

This shows that at least some dinosaurs could move between Africa and Europe near the end of these animals' reign, researchers said.

"Africa's last dinosaurs were not completely isolated, contrary to what some have proposed in the past. There were still connections to Europe," Gorscak added. PTI SAR SAR