While the now-extinct Pleistocene cat was more closely related to the cougar (Puma concolor), it had a highly specialized, fast-running skeleton reminiscent of today’s cheetah (Acinonyx jubatus).
A cheetah in Botswana. (file photo)
Photo: Getty Images / Christophe Baudufe
At first glance, its limbs were designed for speed, at the expense of their ability to grasp prey, explain paleontologist Borja Figueirido and colleagues from the University of Málaga, Spain, in their studies published in Biology Letters (new window) (on English) were published).
But could it really run as fast as today’s cheetah? Or did it rather have a great ability to grab its prey by force? In other words, how did his morphology make him a formidable hunter? Difficult to know as the dexterity of Miracinonyx trumani (M. trumani) forelimbs had never been studied in detail.
A cougar. (file photo)
Photo: Radio Canada / Pier Gagne
It is this work that Danish paleontologists, along with American colleagues from the University of Wisconsin-Madison, have undertaken to come to a rather surprising conclusion.
Using a 3D reconstruction of part of a 24,000-year-old humerus discovered in Wisconsin, scientists reconstructed the morphology of the cat’s elbow joint to compare it to that of 26 specimens from 11 species of current felids, including lion, lynx, puma and Cheetah.
Miracinonyx 101
- There were two species: M. inexpectatus and M. trumani.
- They were larger than today’s cheetah and similar in size to a modern cougar.
- They had a body mass of around 70 kg, but large specimens may have weighed more than 95 kg.
- M. inexpectatus would have disappeared earlier than M. trumani, 600,000 years ago.
A unique predator
Our work shows that M. trumani has an elbow morphology that falls between that of cougars and cheetahs, the researchers say.
In fact, Mr. Trumani’s humerus was oval and elongated at the end nearest the elbow. This feature shows that the bones of its forearms were spread further apart, allowing it to hunt its prey by holding it, as today’s cougars do.
Today, a cheetah hunting in the African savanna can reach 100 km per hour, which was not the case for its prehistoric North American cousin, whose tracking ability was less pronounced.
Although M. trumani had greater manipulative ability thanks to its forelimbs, it exhibited a physiognomy that prevented it from achieving speeds similar to modern-day African cheetahs, the researchers believe.
“So it wasn’t a sprinting predator. […] However, because its claws were retractable, it could grab its prey like other cats except the cheetah. »
— A quote from the authors from the Universities of Málaga and Wisconsin-Madison
So he looked like a cheetah, but he hunted like a cougar.
The researchers believe that M. trumani likely exhibited unique predatory behavior that challenges the degree of ecomorphological convergence between M. trumani and A. jubatus.
The Miracinonyx was not the largest predator in North America at the time, being contemporaneous with the American lion, short-faced bear, and saber-toothed tiger.