The Marsupial Sabertooth

     These unique predators roamed the forests of South America about 30 million years ago.  Although it resembles the sabertooth cats, Thylacosmilus was more closely related to kangaroos!  Alone of all the pouched mammals, only thylacosmilus developed those formidable saber teeth. 

     Their teeth grew continually throughout the animal's life.  Powerful jaw and neck muscles drove those 6 inch long stabbing teeth downwards with great force.  The flanges on the lower jaw formed a protective scabbard when the fangs weren't being used.  This structure is virtually identical to the flanges found on nimravids. 

     Thylacosmilus was roughly jaguar-sized at 4 feet long and 100 kilos.  Unlike the later, more successful sabertooth cats, it had non-retractile claws, short legs, and a heavy build.  Once true cats started moving into South America, Thylacosmilus could not compete and died out.  Thylacosmilus has no known descendants.

THYLACOLEO:

The Marsupial "Lion"

     Another cat-like marsupial animals, the thylacoleonidae, ranged in size from house cat to almost lion proportions.  These predators lived in Australia about 25 million years (Oligocene) ago and some species (T carnifex) survived up until 6,000 years ago.  

     Thylacoleo lacked the big saber teeth, but had large incisors and thick bladed carnassial teeth.  Its bite was the most powerful of any carnivore - alive or extinct!  Thylacoleo killed prey rapidly, using its "bolt-cutter" type teeth to scissor through hide and flesh to produce major trauma and blood loss. Certainly, Thylacoleo was seriously over-engineered for dispatching small prey.  Indeed, its teeth marks have been discovered on the largest marsupial ever: the 3 ton extinct wombat (Diprotodon austalis).   These new findings support the conclusion that the creature regularly preyed on very large species and was able to effect quick kills and withstand large forces generated by large struggling prey.

     Another odd feature was that Thylacoleo's front paws have partly opposable thumbs with a large, curved retractile claw.  The rear feet also had the same type of thumbs, making it a creature with four "hands."  In other words, Thylacoleo could get a good grip on its prey before delivering its powerful killing bite.  Evidence suggests that thylacoleo may have disemboweled its prey. 

     In June 2008, naturalist and tour guide Tim Willing photographed an ancient painting on a rockshelter wall near the shore of northwestern Australia. Kim Akerman, an independent anthropologist based in Tasmania, says the painting unmistakably depicts a marsupial lion.

     The cave painting features Thylacoleo's catlike muzzle, large forelimbs, and heavily clawed front paws. It also portrays the animal with a striped back, a tufted tail, and pointed ears. Those features could not known from just looking at the fossils, so this ancient drawing is our only reference from people who actually were familiar with Thylacoleo.

     Thylacoleo was over 200 pounds and about 2 meters long.  Similar in size to a lion (hence its name), it was undoubtedly the king of the jungle in Australia.  Modern re-constructionists (who like to play) predict unanimously that the marsupial "lion" would eat a modern lion for breakfast if the two were pitted against one another.

     Cryptids, Anyone?

Although the introduction of the Aborigine and the dingo may have sounded the death knell for Thylacoleo, there are some theories that the "Queensland Tiger" of Australia may yet survive.  Occasionally there is a sighting - usually when the beastie disembowels a dog or sheep!  Biologists and cryptozoologists have a lively debate as to whether the "Queensland Tiger" is indeed a thylacoleo or a thylacine. 

     Cave art in Australian depict something very much like the 1964 photograph (top photo) below.  The creature in both photos are most likely thylacines.  The thylacine had rear stripes and a pointed, dog-like muzzle; Thylacoleo had a rounded, more cat-like face and was also much larger.  The last captive thylacine (bottom photo) died in the Hobart Zoo in 1936.  The thylacine in the top photo - which hasn't been proven to be a fake - would suggest that at least one was alive and kicking in 1964!