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EXTINCT ANIMALS
Saber Tooth Cat—The South American Smilodon populator was the largest saber tooth cat as well as one of the largest cats that has ever lived. (Renata Cunha)
The Smilodon species, often called saber tooth cats, are among the most famous of all prehistoric beasts, and the species described here was the biggest and most powerful of Saber Tooth Cat—The skull of Smilodon popula- them all. The Latin name of this cat, Smilotor clearly shows the enormous canines of this for- don populator, can be translated as the “knife midable extinct cat. It used these teeth to inflict tooth that destroys.” Fully grown, S. populafatal wounds on some of the large South Ameritor was the same height and length as a large can herbivorous mammals. (Ross Piper) lion, but much heavier. They were around 1.2 m at the shoulder and may have reached 400 kg—heavier than any big cat alive today. Unlike modern big cats, S. populator had a very stubby tail, and it also had very robust and heavily muscled forequarters—an important adaptation for catching and subduing prey. The bones of S. populator’s forelimbs were relatively short and quite broad, indicating that they were attached to some very powerful muscles. These worked together with the muscles in the shoulders and back to provide tremendous force. Without doubt, the most impressive feature of S. populator is the massive canine teeth in the upper jaw. They were huge—far bigger than any tooth that has graced the mouth of any cat before or since. These formidable curved fangs were around 20 cm long, and to accommodate them, the mouth could open extraordinarily wide, up to 120 degrees (a modern lion’s maximum gape is about 65 degrees). Why did S. populator have such monstrous canines? We know that this predator stalked the earth at the same time as many species of large herbivorous mammals, but it is very unlikely that S. populator was capable of subduing the adults of the Pleistocene giants: mammoths, mastodons, giant sloths, and the like. However, the young of these giants and a host of other herbivores were well within the predatory abilities of the saber tooth cats, and they represented a feast for any animal that could bring them down. Catching and killing a large herbivore is no mean feat, even for a hugely powerful, 400-kg cat with 20-cm canines. Exactly how S. populator and the other Smilodon species caught and killed their prey has been a bone of contention for decades, but a look at the remains of these long-dead animals does give us some clues. Their stocky build and their relatively short limbs indicate that they were probably ambush predators. They may have skulked behind bushes and other vegetation and pounced on an unfortunate ungulate when it came within range. This is a plausible ex-