The newly identified toothed cat that lived in North America five to nine million years ago weighed around 600 pounds and could have killed its prey ten times its size.
American researchers have named the ferocious cats “Machairodus lahayishup” in honor of the Kaioz people, whose original specimen was discovered on its soil.
In Old Cayuse, “Laháyis Húpup” means ancient wild cats, 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 were present early in the evolution of sword-toothed cats, but more 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 around 10,000 years ago.
The new species was mainly recognized by their formidable forearms, a feature that saber-toothed cats use to subdue their prey.
The newly identified toothed cat that lived in North America 5-9 million years ago weighed about 600 pounds and would have killed its prey ten times its size. Pictured: An artist’s impression of M. lahayishupup eating Hemiauchenia, a relative of a camel
Live: 5-9 million years ago
Location: North America
Average Weight: 600 lbs (272 kg)
victim: Rhino, Sloths and Hemiauchenia
The study was conducted by biologist Jonathan Calidi of Ohio State University and John Orcott of Gonzaga University in Spokane, Washington.
“We think these were animals that routinely killed animals the size of oxen,” said Professor Kaleid.
“This was by far the largest surviving cat.”
The duo’s investigation began since Professor Orcott was now a graduate student and discovered a large bone in the arm at the University of Oregon Museum of Natural and Cultural History that was described, mysteriously, as being from a cat.
The researchers found six other unclassified mannequins in various collections, including the University of California Paleontology Museum, Texas Memorial Museum and Idaho Museum of Natural History.
In the latter case, the large cat’s forearm was accompanied by teeth, which are generally considered the gold standard for identifying new species.
The largest fossils of M. lahayishup humerus that they found were over 18 inches (46 cm) and 1.7 inches (4.3 cm) in diameter.
For comparison, an adult male lion’s upper arm bone is about 13 inches (33 cm) long.
American researchers have named the ferocious cats “Machairodus lahayishup” in honor of the Kaioz people, whose original specimen was discovered on its soil. 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 big stories of all of this is that we’ve ended up spotting sample after specimen of this giant cat in museums in western North America. Professor Orkut said: “ They are clearly big cats.
We started with some assumptions based on their ages, in a range of 5.5 to 9 million years old, and based on their size, because these things were huge.
“What we didn’t have at the time, which we have now, is a test of whether the size and anatomy of those bones tell us anything – and it turns out that yes, they do.”
To demonstrate that the elbow portion of the humerus can be used in conjunction with the teeth to distinguish large cat species, the duo analyzed forearm samples from tigers, lions, pumas, cheetahs, tigers and other extinct felines from museums around the world.
Professor Kaleid used software that allowed them to model each elbow and identify specific features.
We found that we can spot the differences on a fairly good scale. This told us that we can use the shape of the elbow to differentiate modern big cat species.
Then we took the tool to the fossil record – these gigantic museum elbows they all share. This told us that they are all of the same type.
Her unique shape and size told us that she was also very different from everything that is already known. In other words, these bones belong to one type and this type is a new type.
The new species was primarily identified by their massive forearms, or “humerus” – a feature that saber-toothed cats used to subdue their prey. Pictured: one of the humerus beams
The researchers used the correlation between body mass and forearm size in modern large cats to make their estimates of M. lahayishup’s body size.
They speculated the nature of ancient prey for cats by looking at their size and the animals that lived in the surrounding area at the time – among them were giant land sloths, rhinos, and relatives of giant camels called Hemiauchenia.
Experts note that the only known jaw specimen to date of M. lahayishup is from the mandible – thus, unfortunately, it does not include the iconic saber-shaped fangs for which Machairodus was famous.
However, Professor Orcutt said: “ We are absolutely confident that it is a cat with sword teeth, and we are quite confident that it is a new species of the Machairodus genus.
“The problem is that our understanding of how all these lower-toothed cats relate to each other is a bit vague, especially early in their development.”
In particular, Professor Orkut explained that researchers haven’t had the clearest picture in the past of exactly how many types of giant cats there are.
He added that discovering that fossil cats can be recognized based on their muscles alone may help improve this understanding – as the “ big, fat ” forearms of cats with blasted teeth are the most common for their remains that can be found in fossils.
Researchers found seven unclassified Humerids in various museum collections, including the University of California Museum of Paleontology, Texas Memorial Museum and Idaho Museum of Natural History. In the latter case, the big cat’s forearm was accompanied by teeth (pictured) – which is generally considered the gold standard for identifying new species.
“Giant cats have been known to exist in Europe, Asia and Africa – and now we have our giant saber-toothed cats in North America during this period as well,” said Professor Kaleid.
There is an interesting pattern of independent evolution repeated on every continent of this gigantic body size, while still being a highly specialized fishing method.
“Other than that, we have this giant, saber-toothed ancestor that has spread to all those continents. It’s an interesting palaeontology question.
The full results of the study have been published in the Journal of Mammalian Evolution.
The most famous saber-toothed cat: SMILODON
Pictured: An artist’s impression of Smilodon is swept away
Smilodon is a genus of toothed cats that lived from 2.5 – 0.01 million years ago in the forests and shrubs of the Americas.
It is generally known as a saber-toothed tiger, although it is not closely related to modern tigers or other modern cats.
However, they would have been roughly the same size as today’s big cats, if built with a more robust frame.
There are three known species in total – S. gracilis, S. fatalis, and S. populator – and the majority of specimens have been recovered from the La Brea Tar pits in Los Angeles, California.
It is believed to have been caught by catching its prey with its large forearms before presenting a fatal bite.
Smilodon prey included large herbivores such as bison and camels.