Smilodontini is an extinct tribe within the

Machairodontinae Machairodontinae (from Ancient Greek μάχαιρα ''Makhaira, machaira,'' a type of Ancient Greek sword and ὀδόντος ''odontos'' meaning tooth) is an extinct subfamily of carnivoran mammals of the cat family Felidae, representing the ...

or "saber-toothed cat" subfamily of the

Felidae Felidae ( ) is the Family (biology), family of mammals in the Order (biology), order Carnivora colloquially referred to as cats. A member of this family is also called a felid ( ). The 41 extant taxon, extant Felidae species exhibit the gre ...

. The tribe is also known as the "dirk-toothed cats". They were found in

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Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

Asia Asia ( , ) is the largest continent in the world by both land area and population. It covers an area of more than 44 million square kilometres, about 30% of Earth's total land area and 8% of Earth's total surface area. The continent, which ...

, and

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during the

Middle Miocene The Middle Miocene is a sub-epoch of the Miocene epoch (geology), epoch made up of two Stage (stratigraphy), stages: the Langhian and Serravallian stages. The Middle Miocene is preceded by the Early Miocene. The sub-epoch lasted from 15.97 ± 0. ...

to early

Holocene The Holocene () is the current geologic time scale, geological epoch, beginning approximately 11,700 years ago. It follows the Last Glacial Period, which concluded with the Holocene glacial retreat. The Holocene and the preceding Pleistocene to ...

, from 10.3 mya—8,200 years ago. As the name suggests, the famous genus of ''

Smilodon ''Smilodon'' is an extinct genus of Felidae, felids. It is one of the best known saber-toothed predators and prehistoric mammals. Although commonly known as the saber-toothed tiger, it was not closely related to the tiger or other modern cats ...

'' is part of this group, but there are also three other distinct genera in Smilodontini. The earliest known genus of the tribe is '' Promegantereon'', once thought to be a species of '' Paramachairodus''. The tribe only became extinct 10,000 years ago, with the demise of ''Smilodon''. All of these are saber-toothed cats, meaning that they have long, narrow upper canines and stocky, well muscled proportions.

Description

The various members of Smilodontini are generally distinguished by their long, narrow upper canines. However, the stockiness often seen as one of the tribe's signature features varied between the different genera. ''Promegantereon'' and '' Paramachairodus'' for example, were likely arboreal or at the least,

scansorial Arboreal locomotion is the locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally (scansorial), but others are exclusively arboreal. The habi ...

, given their moderately long tails, large dewclaws and smaller, slender builds. These species also had relatively small upper canines for their size, though they already showed the flat, blade-like edges that defined them as those of machairodonts. ''

Megantereon ''Megantereon'' is an extinct genus of prehistoric machairodontine saber-toothed cat that lived in Eurasia, Africa and possibly North America from the late Pliocene to the Middle Pleistocene. It is a member of the tribe Smilodontini, and close ...

'', a later species, was more intermediate in physiology between these earlier forms and the more

cursorial A cursorial organism is one that is adapted specifically to run. An animal can be considered cursorial if it has the ability to run fast (e.g. cheetah) or if it can keep a constant speed for a long distance (high endurance). "Cursorial" is often ...

'' Rhizosmilodon'' and ''Smilodon'' itself, which were better built for life on ground, as well as bringing down relatively larger prey.

Classification

Phylogeny

The phylogenetic relationships of Smilodontini are shown in the following cladogram:

Paleobiology

Like all machairodonts, smilodontins were equipped to hunt and kill prey in a manner that was seemingly quicker and more efficient than what is seen in modern cats like the

pantherinae The Pantherinae is a subfamily of the Felidae; it was named and first described by Reginald Innes Pocock in 1917 as only including the ''Panthera'' species, but later also came to include the clouded leopards (genus ''Neofelis''). The Pantherin ...

. Using their elongated canines, smilodontins would aim for the vital spots of the neck or belly (the exact placement of such bites is still hotly debated among experts), killing either by disembowelment of by severing major arteries such as the carotid. The enlarged carnassials would then be used to shear meat from the bones as the cat fed. In regards to feeding habits, the carnassials of ''Megantereon'' suggest that it was a loner that fed at leisurely paces in deep bushes or in trees, while ''Smilodon'' on the other end of the spectrum, lived in what was probably a highly competitive environment and in addition, seems to have been social, suggesting a need to eat as much as possible without losing a meal to scavengers.

References

{{Taxonbar, from=Q2262856 Machairodontinae Mammal tribes