These simulations indicated that the cheekbones of S. occidentalis supported large muscles that prevented dislocation of the jaw when the animal used its powerful bite. "Interestingly, the short-faced kangaroo models were found to have a much higher risk of injury than the koala models during biting at the back teeth," Mitchell said. "This is because its teeth were much larger and extended farther back towards the jaw joints. This greatly increased how hard the animal could bite, but also increased the risk of jaw dislocation when biting." "However, I found that an enlargement of a muscle located on the inner surface of its immense cheekbones would help to reduce this risk," he said. This muscle is also enlarged in the giant panda, another similarly sized animal that feeds on thick, resistant vegetation such as bamboo. Furthermore, the scientist found that the bones of the front and roof of the skull provided sufficient structural support to resist the twisting forces that would have been generated during these bites. This finding supports previous suggestions about short-faced kangaroos that the toughest, thickest vegetation that it could have eaten, such as the woody twigs and branches of trees and shrubs, may have been fed directly to its premolars and molars to be crushed or otherwise broken apart. Such actions would appear similar to how giant pandas crush bamboo," he said.
The team proposed that this unique elbow joint, in combination with the huge ‘dew claw’ on a mobile thumb, would have allowed the marsupial lion to use that claw to kill its prey.
