Restoration of the skull of Thylacoleo. From The Ancient Life History of the Earth.

But what kind of predator was Thylacoleo? Some have proposed that it hunted down prey and then dragged it into the trees, as a leopard does, while others have argued that it was more lion-like in habit. The entire argument hinges upon whether Thylacoleo could climb trees or not, which in turn rests on our understanding of the predator’s anatomy. The details of the skeleton of Thylacoleo, particularly its hands and feet, can provide paleontologists with clues as to what it was capable of. Unfortunately scientists have had to cope with an incomplete understanding of the hind feet of Thylacoleo for years,