One of the last dinosaurs roaming Africa when the fatal asteroid hit the planet some 66 million years ago has been discovered in a mine in Morocco. The incredibly rare find, which is a fragment of jaw belonging to a large carnivorous dinosaur, helps build a picture of what Africa looked like at the end of the Cretaceous.
While much is known about the plants and animals living in North America during this period, almost nothing is known about what was going on in Africa. Identified as belonging to a type of Abelisauroid known as Chenanisuaurs barbaricus, the fossil helps to show how the continent, which had already split from South America by this time, had its own unique and diverse species prowling about.
“We have virtually no dinosaur fossils from this time period in Morocco – it may even be the first dinosaur named from the end-Cretaceous in Africa,” explained Dr Nick Longrich, who helped describe the fossil in the study published in Cretaceous Research. “It's also one of the last dinosaurs in Africa before the mass extinction that wiped out the dinosaurs. It's an exciting find because it shows just how different the fauna was in the Southern hemisphere at this time.”
The beast would have sat right at the top of the food chain. Strutting around on its back legs, it would have looked not unlike the larger and more famous Tyrannosaurus rex over in North America. But if you thought that T. rex had little arms, then you haven’t seen anything yet, as Chenanisaurus had tiny little nubs for hands. Yet with a large, blunt snout filled with worn down teeth, the researchers suspect that the dinosaur would have been taking down herbivores and crunching on their bones.
What is also striking about this latest discovery, however, is where it was found. Unearthed in a phosphate mine in northern Morocco, at the time the dinosaur was alive, towards the end of the Cretaceous, this region would have been a shallow sea. “It's a bit like hunting for fossil whales, and finding a fossil lion,” says Dr Longrich, who compared the finding to winning the lottery. He suggests that while the dinosaur died on land, the carcass was then washed out to sea, where it subsequently sank to the bottom and was covered in silt.
Because the sea levels were so much higher when the asteroid struck, large parts of Africa were at the bottom of a shallow sea. This has hampered the attempts of paleontologists looking for fossils that might help paint a picture of what was going on above the waves in Africa at this time.