The Tasmanian tiger, or thylacine (Thylacinus cynocephalus), is a now-extinct marsupial that once roamed Australia. Despite its name, which might suggest a connection to tigers or other felines, a new study by Australian researchers reveals that its skull structure is not closely related to those of cats or dogs. Instead, the analysis of the thylacine's skull suggests that it may have hunted in a way more similar to crocodiles. The last known thylacine died in captivity in 1936, so scientists now use fossil remains to learn more about its physical traits and behavior. As the largest marsupial predator, the thylacine developed a shape resembling canids (dogs) during its development in the mother's pouch, even though marsupials and placental mammals have been evolving separately for about 160 million years. A detailed 3D study of the thylacine's skull, published in Nature Communications, places it halfway between canids and metatherians, which include marsupials and their extinct relatives. The study found that the thylacine’s skull most closely resembles that of medium-sized canids that specialize in hunting small prey, such as jackals and foxes. However, the thylacine’s skull is unusually large for its body size. For example, while the animal weighed around 17 kg, its skull size is comparable to those of species that weigh between 24.5 and 66.7 kg. This suggests that the thylacine had a powerful bite force relative to its size. The shape of the thylacine's skull—long and narrow—implies a different kind of bite compared to other predators. This might mean the thylacine could not effectively attack large prey that could struggle or that it would have had to shake or drag down. The mechanical features of the skull make the thylacine unique among modern mammals, with no direct equivalent in living species. Its skull structure and function distinguish it from other carnivores, indicating a specialized hunting method. The study raises questions about how the thylacine hunted, as researchers can only infer its behavior by comparing it to other carnivores with similar skull shapes. However, no living species have the exact same features as the thylacine. Researchers found similar traits in aquatic animals like crocodiles and predatory fish, as well as in extinct species like Spinosaurus and pterosaurs. However, the thylacine was not a fish-eater. The study also highlights that several extinct land mammals had similar skull structures, suggesting the thylacine may have had biomechanical adaptations for carnivory that are now rare in modern mammals. Vera Weisbecker, an evolutionary biology researcher at Flinders University and lead author of the study, points out that thylacines were hunted due to myths portraying them as fierce predators of livestock, despite little evidence supporting this. Their extinction was the result of misunderstanding and a lack of appreciation for Australia’s unique wildlife and the knowledge of Indigenous Australians, who have long been its guardians.