With the earth being billions of years old many lost histories due to extinctions and the evolution of animal ancestors are beginning to resurface via discoveries. And one of those big discoveries is the giant prehistoric lion which Matthew Borths discovered during a lunch break.

Borths is a carnivore paleontologist at the National Museum of Nairobi, Kenya. He made his new discovery while he was examining drawers at the museum where he works. While he opened a drawer of Ice Age Specimens, he noticed a row of huge teeth right within the box. What Borths had just discovered weren’t Ice Age Specimens instead, something that dates nearly 22 million years ago.

Taking a quick step backward, Another Paleontologist at the Ohio University, Nancy Stevens had seen these drawers and teeth some years ago. The fossils which sates as far back as 22 million years ago were unearthed by Kenyan researchers who were scouring the African plains while looking for ancient ape bones some decades ago.

The problem here is that they had hidden away a wrong museum specimen for so many years. The discovery made by Borths in conclusion with Nancy was that this was a prehistoric lion species. They were able to examine portions of the creature’s skull and also it’s jaw and other parts of the skeleton whereby they discovered this was the oldest specimen of a group of mammals known as the Hyaenodonts.

They soon name their discovery after a Swahili name Simbakubwa Kutoaafrika which means Big Lion from Africa. In their report, they announced that the creature is much larger than a polar bear and had canine teeth which are big as the foot of an adult.

The researchers believe that Simbakubwa was one of the apex predators of its era and although it is part of the hyaenodont group, it is unrelated to modern-day hyenas. 

“From its teeth, we can tell Simbakubwa was a hypercarnivore, which means its diet was over 70% meat,” says Borths. “Simbakubwa barely has any grinding surfaces on its teeth, so it wouldn’t have processed food that wasn’t meat very efficiently.”

Also part of their analysis suggests that the animal originated in Africa some 30 million years ago while moving further north over time as the continents of Africa and Eurasia collided. At the same time, the ancient relatives of modern day cats, hyenas and dogs began to filter south.

“It’s a fascinating time in biological history,” Borths says. “Lineages that had never encountered each other begin to appear together in the fossil record.”

But Simbakubwa ultimately went extinct around 10 million years ago as global ecosystems shifted thanks to tectonic movement and changing climates. Borths and Stevens have been investigating why that might be, hoping to better inform present-day studies of how ecosystems respond to these sweeping changes.

“Understanding large-scale patterns of how organisms respond to environmental change through time can offer insights into ecosystem fragility and resilience in the modern world,” explains Stevens.

And to think, it would have remained off the fossil record entirely, if not for a Kenyan museum storing away the sample and some inquisitive paleontologists checking a few extra drawers.

“Discoveries like this one underscore the importance of museums as troves of information about our planet’s past,” says Stevens.