Also known as the Tasmanian wolf or the Tasmanian tiger (I prefer wolf). I have a huge love for this animal. It's not quite a feline nor a canine, it's a marsupial. It extinted because of humans (by hunting and by introducing dogs to the Tasmanian island). I do believe that they may return, whether by cloning or by finding one who's still alive. From Wikipedia: "It has been described as a formidable predator because of its ability to survive and hunt prey in extremely sparsely populated areas".
