Sunday, September 26, 2010
As promised in my previous post on walruses - Iemisch and sabretooth cats, I did my reading last night and can conclude that: (1) yes, there were sabretooth cats in Patagonia (one of which was not a cat but ia cat-like marsupial) and (2) it is unlikely that they are the Iemisch though they may, if still alive, be some other Patagonian monster (i.e. the water tiger, if and when Iemisch and water tiger are not the same animal, though I believe they are one and the same).
Patagonian sabretooth "cats"
The real felid, the Smilodon populator whose remains seem to have been found among the bones collected at at the “Mylodon Cave” (see my post on Mylodon) as disclosed by recent analysis of old collections (Barnett et al. 2005 and Massone 1996).
Then we have the "false" sabretooth cats, the Thylacosmilids. They were predators that became extinct during the Pliocene Epoch, and were large, as big as modern pumas. They had short tails and lived in South America since the Miocene (some 15 Million years ago) and, as most of the marsupials in South America, they were displaced by the later arrivals which were placental (i.e. the smilodons) about 1 Million years ago, becoming extinct.
Thylacosmilids were not "cats" (which are placental mammals), they were marsupials (like the kangaroo, and their young developed after birth in their mother's pouch), fierce carnivores with pouches!
Their name in Greek means "pouch knife" due to their long long upper fangs (15 cm – 6 in.) which rested against their chins, of solid bone, which had flanges thad guided and protected these big yet fragile canines. Unlike felines, Tylacosmilids lacked incisors, their teeth cheek were marsupial.
Smilodons (Greek for “knife teeth”) on the other hand lived well into the Late Pleistocene (about 10,000 years B.P.). They were real cats: the feline ancestry of Smilodon has been confirmed by DNA, and were about 1.2 m (4 ft.) long they had Short tails (bold font mine: this makes them unlikely candidates for our “Walrus” because the image (here) shows a long tailed beast) and enormous upper canines (walrus-like) about 18 cm (7 in.) long (but could reach 25 cm or 10 in).
These big “cats” one marsupial and the other placental were virtually identical to each other despite having different origins. This is a clear example of converging evolution, where a good design is repeated again and again because it is the most suitable one. Similar converging evolutionary examples can be found in: the shark (fish), ichtiosaur (reptile) and dolphin (mammal) as marine animals or, in the pteranodon (reptile), birds and bats (mammals) as flying animals.
Getting back to our Sabre teeth, what made them disappear?
They became extinct with all the megafauna at the end of the Last Ice Age. Perhaps the irruption of humans in America tipped the predator-prey balance and led to their demise, or the climate changes could have also affected them. It is still an unsolved question.
The short tail, has a superficial resemblance to the lynx or bob-cat’s tail, but the similarity ends there. They were stocky, had short limbs and do not seem to have been built to run after them. They must have stalked them and ambushed them. Using their massive bodies to push and pin down their prey, which they would hold down with their big paws and then, as its horrid teeth were quite fragile, they must have just used them to bite and cause a dreadful wound. They hunted statically, not “on the run”. Perhaps this specialized hunting mode led to their extinction. 
Both of these cats lived in Patagonia, and there is a faint chance that they may have survived and lived on to frighten the natives and became incorporated into their myths.
As I said at the beginning of this post, they may be reflected in the "Water Tiber" myth or even in the "Iemisch" myth, however I disagree because their short tails are very unlike the long tailed being that the Iemisch is supposed to be or, the long tailed nguruvilu fox-snake.
 Barnett, R., Barnes, I., et al. (2005). Evolution of the extinct Sabretooths and the American cheetah-like cat. Current Biology. vol 15. No 15.
 Massone, M. (1996). Hombre temprano y paleoambiente en la región de Magallanes: evaluación crítica y perspectivas. Anales del Insituto de la Patagonia 24:81–97. P. Arenas
 McHenry et al. (2007). Supermodeled sabercat, predatory behavior in Smilodon fatalis revealed by high-resolution 3D computer simulation . Proceedings of the National Academy of Sciences of the United States of America, 104 16010-16015. 10.1073/pnas.0706086104.
Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia2010 International Year of Biodiversity Copyright 2009-2010 by Austin Whittall ©