Thylacoleo (Thylacoleo carnifex)

Family: Thylacoleonidae

Order: Diprotodontia

"Thylacoleo carnifex was the largest member of an extinct group of marsupial predators know as the thylacoleonids which lived in Australia from Late Oligocene times until the end of the last Ice Age. Members of this marsupial family varied in dimensions from that of a house cat to nearly the size of an African lion. The most famous thylacoleonid was Thylacoleo carnifex, more popularly known as the "Marsupial Lion" due to its large size." "Its head was broad with a blunt rostrum and forward facing binocular eyes supported on a thick muscular neck. The dentition of Thylacoleo is among its most peculiar features, possessing a set of large stabbing maxillary and mandibular first incisors. Thylacoleo also sported a set of gigantic upper and lower slicing third premolars which would have been used to slice through meat. The dentition is essentially similar to that of the phalangerid marsupials, except that there is a reduction in the size and number of molars."

"First described in 1859 by the distinguished British paleontologist Sir Richard Owen as 'the fellest and most destructive of predatory beast', the idea of Thylacoleo as a carnivore soon became a topic of debate." Different interpretations of the Thylacoleo's dentition led other paleontologists to compare them to marsupials which had essentially herbivorous diets. "Owen never wavered from his original theory and with the passing of 140 years and more than 40 scientific papers, the general view of Thylacoleo now agrees with his original interpretation."

"Thylacoleo is thought to have been primarily an arboreal (tree dwelling) animal which possessed a strong grip. Skeletal remains indicate a powerful hand with robust digits capable of grasping and supporting its weight while climbing. Another notable feature of the hand was the presence of a large, hooded claw on the thumb that would have been used as a weapon and was capable of moving independently of the other digits." "When standing, the weight of the animal would have been borne by the ends of the toes in a similar way as that seen in cats. In spite of this, Thylacoleo's hand would have had a powerful grip through opposition of the thumb, not to the other digits as in primates, but to a flattened bone (the pisiform) in the wrist. "The structure of the hind foot implies that the weight of the animal was distributed along the side of the foot (a plantigrade stance) and was very similar in design to that of the Brush-tailed possum" providing further evidence of a tree dwelling ancestry.

Information courtesy of Cameron Campbell from The Thylacoleo Remembrance web site. For a more detailed, in-depth look at Thylacoleo carnifex and related species please visit The Thylacoleo Remembrance