With enormous, flying predatory reptiles, dinosaurs, and crocodile-like hunters once roaming the landscape, 100 million years ago, the Sahara was the most dangerous place on the planet, according to palaeontologists.

Located along the border of Morocco and Algeria is the Kem Kem Group, a well-documented and highly fossiliferous rock formation that holds records of Earth’s lifeforms spanning tens of millions of years. Here, the fossilized remains of cartilaginous and bony fishes, turtles, pterosaurs, dinosaurs, as well as plants and trace fossils have been documented by palaeontologists for decades. The Kem Kem Formation has an unusually high amount of large-bodied carnivores and captures the diversity of northern Africa better than any other assemblage found from the continent.

Publishing their work in Zookeys, an international team of scientists compared decades’ worth of expedition notes and records from Kem Kem, as well as reviewed data sets of fossil records housed in museums around the world. The result is what researchers call the “most comprehensive piece of work on fossil vertebrates from the Sahara in almost a century,” and provides insights into the location and date of when and where they think was the most dangerous place to be in the history of Earth.

During the Cretaceous period, the area surrounding Kem Kem was once home to a vast river system home to different species of aquatic and terrestrial animals. The fossils indicate at least three of the largest predatory dinosaurs ever documented, including the 8-meter-long saber-toothed Carcharodontosaurus and the similarly sized Deltadromeus raptor, as well as pterosaurs – which are basically giant flying crocodiles, roamed there. 

“This was arguably the most dangerous place in the history of planet Earth, a place where a human time-traveler would not last very long,” said lead author Dr Nizar Ibrahim, an Assistant Professor of Biology at the University of Detroit Mercy, in a statement.

Just as terrifying as the giant animals that roamed the landscape were the animals that they preyed upon – huge, terrifyingly monstrous fish.

"This place was filled with absolutely enormous fish, including giant coelacanths and lungfish. The coelacanth, for example, is probably four or even five times large than today's coelacanth. There is an enormous freshwater saw shark called Onchopristis with the most fearsome of rostral teeth, they are like barbed daggers, but beautifully shiny,” said study co-author Professor David Martill from the University of Portsmouth. 

The authors add that the review "provides a window into Africa's Age of Dinosaurs."