A new species of giant mammal has been identified after researchers investigated bones that had been kept for decades in a Kenyan museum drawer.
The species, dubbed "Simbakubwa kutokaafrika" meaning "big African lion" in Swahili, roamed east Africa about 20 million years ago, reports BBC.
But the huge creature was part of a now extinct group of mammals called hyaenodonts.The discovery could help explain what happened to the group.
Hyaenodonts - so called because their teeth resemble those of a modern hyena - were dominant carnivores more than 20 million years ago, National Geographic reports.
But they are not related to hyenas.
"Based on its massive teeth, Simbakubwa was a specialised hyper-carnivore that was significantly larger than the modern lion and possibly larger than a polar bear," researcher Matthew Borths is quoted by AFP news agency as saying.In 2013 he was doing research at the Nairobi National Museum when he asked to look at the contents of a collection labelled "hyenas", National Geographic says.
The creature's jaw and other bones and teeth had been put there after being found at a dig in western Kenya in the late 1970s.
Mr Borths teamed up with another researcher, Nancy Stevens, and in 2017 they began analysing the unusual fossil specimens.
Their findings were reported in the Journal of Vertebrate Paleontology this week.
National Geographic writes: The fossils had been excavated between 1978 and 1980 at a site in western Kenya called Meswa Bridge. So Borths reached out to Ohio University paleontologist and National Geographic grantee Nancy Stevens, who had discovered an important fossil site in Tanzania that’s only a couple of million years older. Their fate was sealed when Stevens told Borths that she had opened the exact same drawer while working in Nairobi and had wondered about its contents.
“It was like the two of us could commiserate, like, Isn’t this amazing, we should do something!” Borths says. Stevens later asked Borths to join her lab as a postdoctoral researcher, and together the two returned to the Nairobi National Museum in 2017 to begin analyzing and describing the specimens, which included most of the animal’s jaw as well as bits of skeleton, skull, and teeth.
Carnivores are often noted for their front canine teeth, which help grab prey, but their back teeth are important, too.
“It’s in the back of the head that this business of slicing through meat takes place,” Borths says. All modern carnivores—including cats, dogs, racoons, wolves, and bears—have one pair of these meat-slicing teeth. Hyaenodonts had three pairs.“This animal had lots of blades,” Borth says.
Aside from their fear factor, the teeth were key to helping the duo grasp the full picture of an extinct species. Without good teeth to study, Borths says, “it’s like having pieces from different sides of the puzzle, and nothing to connect the pieces in between.”
Simbakubwa “brings together tooth information, a little bit of skull information, and a little bit of skeletal information to help unite a lot of this material that’s been floating around. It really helps contextualize this whole group of giant meat-eaters,” he says.
“The science is definitely very impressive,” Tseng adds. “Any time you have a new record of something this large in the fauna and ecological food web, it makes you reconsider exactly what the interactions were like between predator and prey.”