Australia is a large island continent that is home to some of the most diverse biogeographical regions. It is the home of the endemic order Marsupialia. These mammals are unique from the rest of the Mammalia class because the female has a pouch of skin. Some of the best-known marsupials that exist today are the kangaroo, the wombat, and the koala (Thylacoleo Carnifex 2011). However, most people today are unaware of a species of carnivorous marsupials that once roamed Australia over 6,000 years ago. Thylacoleo carnifex, or better known as the marsupial lion, was the largest known carnivorous mammal in Australia (Campbell 1999). its name Thylacoleo, meaning pouch lion, and carnifex, meaning butcher or tormentor, fit perfectly with its predatory status. Although its name may suggest that it was a close relative of modern lions, T. carnifex was more closely related to koalas (Campbell 1999). The remains of the first marsupial lion were originally discovered by Thomas Mitchell of Wellington Valley in New South Whales in the early 1830s (Owen 1887). Mitchell came to the conclusion that a large extinct carnivore had previously existed due to a fossilized tooth he discovered in the valley. All future fossil remains from there and other locations were sent to the British paleontologist Sir Richard Owen. In 1859, Owen was the first to describe the fossil and related it to the extinct species Thylacoleo carnifex. This would be one of the first mammal fossils discovered in Australia. Owen would describe the creature as "one of the cruelest and most destructive of predatory beasts" (Owen 1887). For the next 100 years, the lion was found only in small fragmented fossils (Owen 1887). From the middle of the sheet they do not suggest attempts to break (Horton and Wright 1981). It is perhaps too premature to explore a further paleoecological implication, namely that humans who settled in Australia from the land bridge competed with Thylacoleo carnifex for megafaunal meat resources (Horton and Wright 1981). To date, no archaeological discovery has been found that, from the fossil record, predicts that humans could have killed and eaten the megafauna and depleted the food supply for Thylacoleo carnifex. From the fossil record we can only describe how the animal and its diet might have lived. There is not yet enough evidence to prove that humans killed the lions. However, like most of the megafauna that became extinct after the Ice Age, Thylacoleo carnifex failed to adapt well enough (Trivedi 2004).