US researchers named the wild cat “Machairodus lahayishupup” in honor of the Cayuse people on whose land the original specimen was excavated.
In Old Cayuse, “Laháyis Húpup” means an old wild cat, while “Machairodus” is a well-known genus of giant saber-toothed cats from North America, Africa and Eurasia.
The team believes the newly identified species existed early in the saber-toothed cat evolution, but further research will be needed to confirm this.
M. lahayishupup is also a relative of Smilodon – arguably the most famous of the saber-toothed cats – which became extinct about 10,000 years ago.
The new species was identified primarily by its massive forearms, a trait used by saber-toothed cats to subdue their prey.
A newly identified saber-toothed cat that lived in North America 5 to 9 million years ago weighed about 600 pounds and could have killed prey ten times its size. Pictured: an artistic impression of M. lahayishupup eating a Hemiauchenia, a relative of the camel
Lived: 5 to 9 million years ago
Place: North America
A V. Weight: 272 kg
Prey: Rhinos, sloths and hemiauchenia
The study was conducted by biologists Jonathan Calede of Ohio State University and John Orcutt of Gonzaga University in Spokane, Washington.
“We believe these were animals that routinely killed bison-sized animals,” said Professor Calede.
“This was by far the largest living cat at the time.”
The duo’s investigation came from the time Professor Orcutt was a graduate student and discovered a large humerus at the University of Oregon’s Museum of Natural and Cultural History that had been vaguely labeled as being from a cat.
The researchers found another six uncategorized humeri in various collections, including the University of California Paleontological Museum, Texas Memorial Museum, and Idaho Museum of Natural History.
In the latter case, the big cat’s forearm was accompanied by teeth, which are widely considered to be the gold standard for identifying new species.
The largest M. lahayishupup humerus fossils found were more than 46 cm in diameter and 4.3 cm in diameter.
For comparison, the humerus of the average modern adult male lion is approximately 13 inches long.
US researchers named the wild cat “Machairodus lahayishupup” in honor of the Cayuse people on whose land the original specimen was excavated. In Old Cayuse, “Laháyis Húpup” means “old wild cat” while “Machairodus” is a well-known genus of giant saber-toothed cats from North America, Africa and Eurasia
“One of the great stories of all of this is that we spotted specimens after specimens of this giant cat in museums in western North America. They were clearly big cats, ”said Professor Orcutt.
“We started with some guesswork based on their ages ranging from 5.5 to 9 million years ago and their size because these things were huge.
“What we didn’t have then and now is the test of whether the size and anatomy of these bones says anything – and it turns out that it does.”
To prove that this elbow portion of the humerus next to teeth can be used to differentiate species from big cats, the duo analyzed forearm samples from jaguars, lions, pumas, panthers, tigers, and other extinct cats from museums around the world.
Professor Calede used software that allowed them to model each elbow and mark the defining features.
“We found that we can quantify the differences on a fairly fine scale. This told us we could use the elbow shape to distinguish species of modern big cats, ”he explained.
“Then we took the tool to the fossil record – those giant elbows scattered around museums all had a common trait. This told us that they were all of the same species.
‘Their unique shape and size showed us that they are also very different from anything that is already known. In other words, these bones are of a species and that species is a new species. ‘
The new species was identified primarily by its massive forearms or “humeri” – a trait used by saber-toothed cats to subdue their prey. Pictured: one of the humeri
The researchers used the relationship between body mass and forearm size in modern big cats to make their estimates of the height of M. lahayishupup.
They speculated on the nature of the ancient cat’s prey by looking at its size and the animals that lived in the area at the time – including giant ground sloths, rhinos, and giant camel relatives called Hemiauchenia.
The experts determined that the only previously known specimen of M. lahayishupup’s jaw originated from the lower jaw – and therefore unfortunately does not contain the iconic saber-shaped canines that Machairodus is known for.
However, Professor Orcutt said, “We are fairly confident that it is a saber-toothed cat, and we are fairly confident that it is a new species in the Machairodus genus.
“The problem is, our understanding of how all these saber-tooth cats are related is a little hazy, especially at the beginning of their development.”
In particular, researchers in the past haven’t had the clearest picture of how many species of giant cats there were, Professor Orcutt explained.
The discovery that fossil cats can be identified by their humeri alone could improve that understanding, he added, since saber-toothed cats’ “big, stout” forearms are the most common remains found during excavations.
The researchers found seven uncategorized humeri in various museum collections, including the University of California Paleontological Museum, Texas Memorial Museum, and Idaho Museum of Natural History. In the latter case, the big cat’s forearm was accompanied by teeth (Figure), which are generally considered the gold standard for identifying new species
“It is known that there were giant cats in Europe, Asia and Africa – and now we have our own giant saber-toothed cat in North America during this period too,” said Professor Calede.
“There is a very interesting pattern of repetitive independent development on every continent of this huge size, which remains a fairly hyper-specialized type of hunt.
“Otherwise we have this huge saber-toothed cat of our ancestors, which spread out over all these continents. It’s an interesting paleontological question. ‘
The full results of the study were published in the Journal of Mammalian Evolution.
THE MOST FAMOUS SABRE TOOTH CAT: SMILODON
Pictured: An artist’s impression of a Smilodon jump
Smilodon is a genus of saber-toothed cats that lived in the woods and bushes of America about 2.5 to 0.01 million years ago.
It is popularly known as the saber-toothed tiger, although it is not closely related to modern day tigers or any other modern day cat.
However, it was about the size of today’s big cats when built with a more sturdy frame.
A total of three species are known – S. gracilis, S. fatalis, and S. populator – with most specimens recovered from the La Brea tar pits in Los Angeles, California.
It is believed that it hunted by holding its prey still with its large forearms before giving off a killer bite.
Smilodon’s prey would have been large herbivores like bison and camels.