An article published in the journal “Paleobiology” describes a research on Thylacoleo carnifex. Commonly known as the marsupial lion, it was a predator native of Australia that lived between the Paleocene period and the beginning of the Pleistocene period, about 50,000 years ago. Christine Janis at the University of Bristol along with Figueirido Borja and Alberto Martín-Serra of the University of Malaga examined this animal’s elbows and concluded that it had a unique hunting style.

The first remains of Thylacoleo carnifex were discovered nearly two centuries ago in Wales but only many years later, in 1859, the species was described by the English paleontologist Richard Owen. Its common name brings a comparison with lions but it was definitely smallest than those big felines because it had a length around 1.5 meters (5 feet), a height of around 75 cm (2.5 feet) and a weight between 80 and 100 kg (175 to 220 lbs). It was still the largest carnivore among marsupials.

Thylacoleo carnifex wasn’t different from lions only in size but also for the differences in its teeth and especially in its limbs. Its common name was due to the idea that it was a predator similar to felines despite the fact that it didn’t have large canines but large protruding incisors that probably had the same function. This new research shows in particular the anatomical features of Thylacoleo carnifex that suggest a hunting style different from that of felines.

The researchers focused on Thylacoleo carnifex’s elbow joint and the consequent motor skills compared with those of other species. Animals specialized for running have joints with movement limited for back and forwards that gives them stability. Thylacoleo carnifex had an elbow joint more similar to that of the climber monkeys that allows a rotation of the hand around the elbow. Cats use their forelimbs to stick to prey and have elbow joints of an intermediate shape.

In essence, Thylacoleo carnifex’s elbow joints suggest that it had a hunting style different from that of lions because they had characteristics of climbers but also various others, useful to stabilize their limbs to the ground. According to the researchers, those joints and the large claw it had on their mobile thumbs allowed this marsupial predator to kill its prey using its claw.

If the researchers are right, Thylacoleo carnifex’s hunting style was opposite to that of lion, which uses its claws to hold its prey and then kill it with its teeth, because Thylacoleo carnifex’s seem more suited to hold its prey to allow it to kill it with its claws. Living predators have a hunting style similar to lions making this marsupial’s hunting style unique, at least among the predators that lived relatively recently.

This reconstruction poses the question of what kind of prey Thylacoleo carnifex hunted. Its claws, as sharp as they were, don’t seem enough to kill large prey. Maybe this animal hunted small prey and brought them on a tree to eat them, as do today’s leopards. Perhaps after all this marsupial’s bite was also useful to kill large prey.