Palaeontologists working in the Egyptian desert have uncovered a nearly complete skull of a leopard-sized predator that would have been at the top of the food chain 30 million years ago.
The skull represents a new discovery from the fossil-rich Fayum Depression, which has been excavated by different palaeontologists for over 120 years.
“Just as we were about to conclude our work, a team member spotted something remarkable — a set of large teeth sticking out of the ground,” recalls lead author Shorouq Al-Ashquar from Mansoura University and the American University in Cairo, Egypt.
“His excited shout brought the team together, marking the beginning of an extraordinary discovery: a nearly complete skull of an ancient apex carnivore, a dream for any vertebrate palaeontologist.”
The team, known as the Sallam Lab, identified the skull as belonging the extinct group of carnivores, Hyaenodonta. Hyaenodonts evolved shortly after the asteroid impact that ended the Age of Dinosaurs during an epoch known as the Palaeogene (66-56 million years ago).
The fossil belongs to a new genus of hyaenodonts, dubbed Bastetodon, after the cat-headed Egyptian goddess Bastet.
While hyaenodonts are ecologically similar to modern day cats, dogs and hyenas, they are not closely related. The group went extinct in the Miocene (23.5 million years ago), potentially due to pressure from other carnivores.
The Fayum Depression captures an important 15-million-year period of climate change and tectonic shifts which brought hyaenodonts in contact with modern day predators.
“The Fayum is one of the most important fossil areas in Africa,” says co-author Matt Borths of Duke University in the United States. “Without it, we would know very little about the origins of African ecosystems and the evolution of African mammals like elephants, primates, and hyaenodonts.”
Bastetodon likely preyed on early hippos, elephants and primates in what was once a lush forest.
The Sallam Lab used the Bastetodon fossil to re-evaluate other hyaenodont fossils found in the Fayum Depression, assigning these older fossil finds to another new genus, Sekhmetops. (Sekhmet is the lion-headed Egyptian goddess of war.)
The Sekhmetops fossils originally described in 1904 were placed within a hyaenodont group originating in Europe. But using anatomical comparisons, the Sallam lab showed that both Sekhmetops and Bastetodon belong to a hyaenodont group that originated in Africa.
“The discovery of Bastetodon is a significant achievement in understanding the diversity and evolution of hyaenodonts and their global distribution,” says Al-Ashquar.
The research supports the theory that relatives of the two new genera spread from Africa in several waves, with descendants reaching Asia, Europe, India and even North America.
“We are eager to continue our research to unravel the intricate relationships between these ancient predators and their environments over time and across continents,” says Al-Ashquar.
The research is published in the Journal of Vertebrate Paleontology.
