Saber-toothed tiger

Smilodon Temporal range: Early to Early Holocene, 2.5–0.01 Ma PreЄ Є O S D C P T J K Pg N ↓
S. fatalis skeleton at National Museum of Natural History, Washington, D.C.
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Carnivora
Family:	Felidae
Subfamily:	†Machairodontinae
Tribe:	†Smilodontini
Genus:	†Smilodon Lund, 1842
Species
S. populator Lund, 1842 (type) S. fatalis Leidy, 1869 S. gracilis Cope, 1880
Synonyms
Genus synonymy Munifelis Muñis, 1845 Trucifelis Leidy, 1868 Smilodontopsis Brown, 1908 Prosmilodon Rusconi, 1929 Smilodontidion Kraglievich, 1948 Species synonymy S. populator: Munifelis bonaerensis Muñis, 1845 Smilodon blainvillii Desmarest, 1860 Machaerodus bonaerensis Burmeister, 1867 Machaerodus necator Gervais, 1878 Smilodon ensenadensis Ameghino, 1888 Machaerodus ensenadensis Ameghino, 1889 Smilodon crucians Ameghino, 1904 Smilodon bonaerensis Ameghino, 1907 Smilodon neogaeus ensenadensis Boule & Thévenin, 1920 Smilodon (Prosmilodon) ensenadensis Rusconi, 1929 Smilodon neogaeus de Paula Couto, 1940 Smilodon necator de Paula Couto, 1940 Smilodon (Prosmilodon) ensenadensis ferox Kraglievich, 1947 Smilodon (Prosmilodon) ensenadensis minor Kraglievich, 1948 Smilodontidion riggii Kraglievich, 1948 Machaerodus neogaeus Pictet, 1953 Felis smilodon Desmarest, 1953 Smilodon populator populator de Paula Couto, 1955 S. fatalis: Felis (Trucifelis) fatalis Leidy, 1868 Trucifelis fatalis Leidy, 1869 Machaerodus fatalis Lydekker, 1884 Drepanodon floridanus Leidy, 1889 Machaerodus floridanus Leidy, 1889 Uncia mercerii Cope, 1895 Smilodon floridanus Adams, 1896 Machaerodus (Smilodon) mercerii Cope, 1899 Smilodon californicus Bovard, 1907 Smilodontopsis troglodytes Brown, 1908 Smilodontopsis conardi Brown, 1908 Smilodontopsis mercerii Brown, 1908 Smilodon nebraskensis Matthew, 1918 Machaerodus mercerii Matthew, 1918 Smilodon (Trucifelis) californicus Merriam & Stock, 1932 Smilodon (Trucifelis) fatalis Merriam & Stock, 1932 Smilodon (Trucifelis) nebraskensis Merriam & Stock, 1932 Smilodon (Trucifelis) californicus brevipes Merriam & Stock, 1932 Smilodon trinitensis Slaughter, 1960 S. gracilis: Machaerodus (Smilodon) gracilis Cope, 1899 Smilodon (Smilodontopsis) gracilis Merriam & Stock, 1932 Megantereon gracilis Broom & Schepers 1946 Ischyrosmilus gracilis Churcher, 1984 Smilodontopsis gracilis Berta, 1995

Smilodon is an extinct genus of machairodont felid. It is perhaps one of the most famous prehistoric mammals, and the best known saber-toothed cat. 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 epoch (2.5 mya–10,000 years ago). The genus was named in 1842, based on fossils from Brazil. Three species are recognized today: S. gracilis, S. fatalis and S. populator. The two latter species were probably descended from S. gracilis, which itself probably evolved from Megantereon. The largest collection of Smilodon fossils has been obtained from the Rancho La Brea Tar Pits in Los Angeles, California.

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 (120 to 220 lb) in weight. S. fatalis had a weight of 160 to 280 kg (350 to 620 lb) and height of 100 cm (39 in). 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 (490 to 880 lb) in weight and 120 cm (47 in) in height. The coat pattern of Smilodon is unknown, but it has been artistically restored with plain or spotted patterns.

In North America, Smilodon hunted large herbivores such as bison and camels, and it remained successful even when encountering new prey species in South America. Smilodon is thought to have killed its prey by holding it still with its forelimbs and biting it, but it is unclear in what manner the bite itself was delivered. Scientists debate whether Smilodon had a social or a solitary lifestyle; analysis of modern predator behavior as well as of Smilodon's fossil remains could be construed to lend support to either view. Smilodon probably lived in closed habitats such as forests and bush, which would have provided cover for ambushing prey. Smilodon died out at the same time that most North and South American 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.