When Ohio University integrative biologist Nancy Stevens peered into a drawer in the wooden cabinets on the top floor of a Nairobi museum in 2010, she saw a chunk of rock containing massive teeth and knew she had come across something important.
The overlooked fossils stored at the National Museums of Kenya belonged to one of the largest meat-eating mammals ever to walk the Earth, a beast called Simbakubwa kutokaafrika that stalked Africa 22 million years ago, according to research by Ms. Stevens and co-author Matthew Borths published on Thursday.
Bigger than any carnivorous land mammal alive today — even a polar bear — Simbakubwa ’s skull was the size of a rhino’s, its eight-inch (20-cm) canine teeth as large as bananas. It weighed about a tonne and was 8 feet long (2-1/2 metres) snout to rump.
According to the research published in the Journal of Vertebrate Paleontology , the fossils were excavated around 1980 in western Kenya.
“Most of the specimens that I study are quite small, so you can imagine my surprise when I opened a drawer that I hadn’t examined yet, and saw the enormous teeth glinting up at me. The specimen had been collected decades before, and the team that discovered this fossil was more focused on other parts of the fauna, particularly primates,” Stevens said.
Simbakubwa was a member of a group called hyaenodonts that appeared 62 million years ago, 4 million years after the extinction of the dinosaurs paved the way for mammalian dominance, and went extinct 9 million years ago.
