抽屉中跑出来的远古猛兽

Ohio University biologist Nancy Stevens was looking through a drawer of a wooden container at a museum in Kenya when she saw a piece of rock with extremely large teeth.

She knew immediately she had come across something important.

The "rock" and other things she found were overlooked fossils. They were stored at the National Museums of Kenya, in the capital city of Nairobi. The fossils came from one of the largest meat-eating mammals ever to walk the Earth.

They belonged to an animal known as Simbakubwa kutokaafrika. It lived in Africa 22 million years ago.

Stevens came across the fossils in 2010. This month, she and co-writer Matthew Borths published their research about the animal in the Journal of Vertebrate Paleontology.

The animal was bigger than any meat-eating mammal alive today. Its skull was the size of a rhino's skull. Its teeth were as large as bananas. It weighed about one ton and was 2.5 meters long.

According to the research, the fossils were found around 1980 in western Kenya. But, they were never closely examined.

Stevens said, "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."

Simbakubwa was a member of a animal group that appeared 62 million years ago. That was about 4 million years after the extinction of the dinosaurs, which created an environment for mammals to take over. The animal came before meat-eating cats and wolves.

It became extinct about 9 million years ago, researchers say.

Simbakubwa's name means "big lion" in the Swahili language. However, it is not a cat. It was the largest animal hunter in its ecosystem, and was probably the largest meat-eating land mammal in Africa up to that time.

I'm Susan Shand.

The Reuters News Agency reported this story. Susan Shand adapted it for VOA Learning English. Ashley Thompson was the editor.

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