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In the fossil-rich sands of the Faiyum Oasis in Egypt, archaeologists have uncovered one of the most complete skulls ever found from a formidable family of predators that roamed the Earth roughly 30 million years ago.The fossil, complete with an upper set of teeth, revealed the animal to be a newly discovered species of extinct hyena-sized mammals known as hyaenodonts, researchers report February 17 in the Journal of Vertebrate Paleontology. This species, Bastetodon syrtos, appears to have fewer teeth than its relatives, a catlike adaptation that would have given it a more efficient bite. The new discovery also redraws the family history of this ancient group of predators.The skull dates back to the Paleogene Period, a time that followed the extinction of the dinosaurs and saw the rapid diversification of many life forms, including mammals. Hyaenodonts were the main meat-eating mammal at the time across what is now Africa and Arabia, and would have hunted through the rich, dense forests which covered the region. These apex predators had large, elongated skulls that housed a lot of teeth. They likely preyed on early elephants, hyraxes and other animals, including our primate ancestors.Scientists discovered the skull of Bastetodon in the sands of Egypts Faiyum Oasis, with its top row of teeth still intact.Shorouq Al-AshqarIn the lab, the researchers scanned the new fossil and re-created it as a 3-D model. The animals long, bladelike back teeth suggested it ate mostly meat, and evidence of strong jaw muscles point to a hefty bite. Yet this hyaenodont had one fewer premolar and molar than its known relatives, an adaptation that would have made its face more compact and its jaw more efficient at closing. Modern cats tooth count has also reduced over time, which is why they have shorter faces than dogs. So the team took inspiration from Bastet, the ancient leonine Egyptian goddess of pleasure, protection and good health, to come up with a new genus for the predator. Bastetodon literally means teeth like the cat-headed goddess.The shortened face reflects what Matthew Borths, a paleontologist at Duke University, calls the pitbullification of hyaenodonts. Compared with other hyaenodonts, its got this short little muzzle that gave it a strong bite, he says.Through comparison with other fossils, Borths and colleagues placed B. syrtos in its family tree and reevaluated the origins of other hyaenodont fossils found at the same site in 1906. Although previously thought to come from Europe, this group including the new hyaenodont all descended from a lineage that arose in Africa. This and other finds suggest that their ancestors left Africa in several waves, eventually spreading through Asia, Europe and as far as North America.
