The saber toothed tiger also known as a smilodon any of the extinct catlike carnivores belonging to either the extinct family Nimravidae or the subfamily Machairodontinae of the cat family (Felidae). Named for the pair of elongated bladelike canine teeth in their upper jaw, they are often called sabre-toothed tigers or sabre-toothed lions, although the modern lion and tiger are true cats of the subfamily Felinae.Smilodon is perhaps one of the most famous prehistoric mammals. Although commonly known as the saber-toothed tiger, it was not closely related to the tiger or other modern cats. Smilodon lived in the Americas during the Pleistocene epoch (2.5 mya–10,000 years ago). Overall, Smilodon was more robustly built than any extant cat, with particularly well-developed forelimbs and exceptionally long upper canine teeth. Its jaw had a bigger gape than that of modern cats, and its upper canines were slender and fragile, being adapted for precision killing. S. gracilis was the smallest species at 55 to 100 kg in weight. S. fatalis had a weight of 160 to 280 kg and height of 100 cm. Both of these species are mainly known from North America, but remains from South America have also been attributed to them. S. populator from South America is perhaps the largest known felid at 220 to 400 kg in weight and 120 cm in height. The coat pattern of Smilodon is unknown, but it has been artistically restored with plain or spotted patterns.
The Smilodon hunted large herbivores such as bison and camels, and is thought to have killed its prey by holding it still with its forelimbs and biting it in the neck. Scientists debate whether Smilodon had a social or a solitary lifestyle; analysis of modern predator behaviour as well as of Smilodon's fossil remains lends support to either view. The Smilodon probably lived in closed habitats such as forests and bush, which would have provided cover for ambushing prey. The Smilodon died out at the same time that most North and South American megafauna disappeared, about 10,000 years ago. Its reliance on large animals has been proposed as the cause of its extinction, along with climate change and competition with other species, but the exact cause is unknown.