US scientists have recently discovered a new type of giant saber-toothed cat that lived in North America between 5 million and 9 million years ago.
During the study, the researchers completed a painstaking comparison of seven uncategorized fossil specimens with previously identified fossils and bone samples from around the world to describe the new species.
Their finding makes a case for the use of the elbow portion of the humerus, to identify a new type of giant cats. The researchers suggest it weighed 900 pounds (400 kg), and could have managed to kill bisons. The study was published in the Journal of Mammalian Evolution on April 2.
John Orcutt, assistant professor of biology at Gonzaga University, found a large upper arm bone specimen that had been labeled as a cat in the University of Oregon's Museum of Natural and Cultural History collection.
He collaborated with Jonathan Calede, an assistant professor of evolution, ecology and organismal biology at The Ohio State University's, on the years-long effort to figure out what kind of cat it could be.
Calede and Orcutt visited numerous museums in the US, Canada and France to photograph forearm specimens of lions, pumas, panthers, jaguars and tigers, as well as fossils of previously identified extinct big cat.
This allowed them to quantify the differences on a fairly fine scale, and told them they could use the elbow shape to tell apart species of modern big cats.
The researchers calculated estimates of the new species' body size based on the association between humerus size and body mass in modern big cats, and speculated about the cat's prey based on its size and animals known to have lived in the region at that time.
"We believe these were animals that were routinely taking down bison-sized animals. This was by far the largest cat alive at that time," said Jonathan Calede in a report published on the Ohio State University's website.