Machairodontini is an extinct tribe of large

saber-toothed cat Machairodontinae is an extinct subfamily of carnivoran mammals of the family Felidae (true cats). They were found in Asia, Africa, North America, South America, and Europe from the Miocene to the Pleistocene, living from about 16 million until ...

s of the

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end subfamily botanical names with "-oideae", and zoologi ...

Machairodontinae Machairodontinae is an extinct subfamily of carnivoran mammals of the family Felidae (true cats). They were found in Asia, Africa, North America, South America, and Europe from the Miocene to the Pleistocene, living from about 16 million until ...

, that lived in

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an area ...

Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...

, and

North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Car ...

, during the Middle and Late

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...

Description

Machairodont means "knife-tooth" which perfectly describes the species that make up Machairodontini. These predators are related to extant cats, the

Felinae The Felinae are a subfamily of the family Felidae. This subfamily comprises the small cats having a bony hyoid, because of which they are able to purr but not roar. Other authors have proposed an alternative definition for this subfamily: as c ...

, and share a common ancestor within the

Felidae Felidae () is the family of mammals in the order Carnivora colloquially referred to as cats, and constitutes a clade. A member of this family is also called a felid (). The term "cat" refers both to felids in general and specifically to the ...

clade. Machairodontines were medium to large sized saber-toothed cats that would have reached a size rivaling

today Today (archaically to-day) may refer to: * Day of the present, the time that is perceived directly, often called ''now'' * Current era, present * The current calendar date Arts, entertainment, and media Films * ''Today'' (1930 film), a 1930 A ...

lion The lion (''Panthera leo'') is a large Felidae, cat of the genus ''Panthera'' native to Africa and India. It has a muscular, broad-chested body; short, rounded head; round ears; and a hairy tuft at the end of its tail. It is sexually dimorphi ...

s, which can reach weights of over . This clade is also occasionally classified as being part of the

Homotherini Homotherini is an extinct tribe (or subtribe) of carnivoran mammals of the family Felidae (true cats). The tribe is commonly known as scimitar-toothed cats. These saber-toothed cats were distributed en North America, Europe, Asia, Africa, and So ...

, and includes genera such as ''

Machairodus ''Machairodus'' (from el, μαχαίρα , 'knife' and el, ὀδούς 'tooth') is a genus of large machairodontine saber-toothed cats that lived in Africa, Eurasia and North America during the late Miocene. It is the animal from which the su ...

'', Hemimachairodus and '' Miomachairodus''. They were first characterized by their

scimitar A scimitar ( or ) is a single-edged sword with a convex curved blade associated with Middle Eastern, South Asian, or North African cultures. A European term, ''scimitar'' does not refer to one specific sword type, but an assortment of different ...

canines in the upper jaw. This means that the canines are shorter and coarsely serrated, with vertical flattening.Antón, Mauricio. 2013. Machairodont adaptations and affinities of the Holarctic late Miocene homotherin Machairodus(Mammalia, Carnivora, Felidae): the case of Machairodus catocopis Cope, 1887. Journal of Vertebrate Paleontology, Vol 33, Issue 5, p. 1202-1213. Although the upper canines are shorter than other more famous saber toothed cats such ''

Smilodon ''Smilodon'' is a genus of the extinct machairodont subfamily of the felids. It is 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 ...

'', they are still abnormally long in comparison to the rest of the teeth in the mandible. There is also a space separating the canines and premolars known as a

diastema A diastema (plural diastemata, from Greek διάστημα, space) is a space or gap between two teeth. Many species of mammals have diastemata as a normal feature, most commonly between the incisors and molars. More colloquially, the condition ...

. The bottom portion of the jaw contains small incisors that are in a straight row with a large, lower canine. These canines are not nearly as big as the upper canines. There is a diastema between the

canines Canine may refer to: Zoology and anatomy * a dog-like Canid animal in the subfamily Caninae ** ''Canis'', a genus including dogs, wolves, coyotes, and jackals ** Dog, the domestic dog * Canine tooth, in mammalian oral anatomy People with the surn ...

and the

premolars The premolars, also called premolar teeth, or bicuspids, are transitional teeth located between the canine and molar teeth. In humans, there are two premolars per quadrant in the permanent set of teeth, making eight premolars total in the mouth ...

in the lower jaw as well. These prehistoric predators not only have long upper canine teeth but they also have elongated limb bones, which differ from the squatter legs of the other group of

saber-toothed cats Sabretooth or sabertooth may refer to: Animals * Saber-toothed cat, several prehistoric felines ** ''Smilodon'', a prehistoric genus of felidae * Sabertooth fish, a deep-sea fish found in the tropics ** Sabre-toothed blenny, ''Aspidontus taenia ...

, the

Smilodontini Smilodontini is an extinct tribe within the Machairodontinae or "saber-toothed cat" subfamily of the Felidae. The tribe is also known as the "dirk-toothed cats". They were endemic to South America, North America, Europe, Asia, and Africa during t ...

. Although not many complete skeletons of machairodontine species have been found, those specimens known illustrate the long limb bones and shorter tails. The tails are of medium length and do not reach the ground as they do with cats today.

Taxonomy

Machairodontini was named by Gill (1872) as well as de Beaumont (1964). It was assigned to

by Berta and Galiano (1983).

Classification

Phylogeny

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

Geologic and geographic distribution

The earliest machairodontine is the genus Miomachairodus from the late middle Miocene in

Turkey Turkey ( tr, Türkiye ), officially the Republic of Türkiye ( tr, Türkiye Cumhuriyeti, links=no ), is a list of transcontinental countries, transcontinental country located mainly on the Anatolia, Anatolian Peninsula in Western Asia, with ...

.Qiu, Zhanxiang. 2003. Dispersals of Neogene Carnivorans between Asia and North America. Bulletin of the American Museum of Natural History, N. 279, p. 18-31. There are also species of the Machairodontini found in Africa from the

late Miocene The Late Miocene (also known as Upper Miocene) is a sub-epoch of the Miocene epoch (geology), Epoch made up of two faunal stage, stages. The Tortonian and Messinian stages comprise the Late Miocene sub-epoch, which lasted from 11.63 Ma (million ye ...

to the

early Pleistocene The Early Pleistocene is an unofficial sub-epoch in the international geologic timescale in chronostratigraphy, being the earliest division of the Pleistocene Epoch within the ongoing Quaternary Period. It is currently estimated to span the time ...

, in deposits such as Lothagam, Sahabi, and Langebaanweg. The Machairodontini moved East during the

Vallesian The Vallesian age is a period of geologic time (11.6–9.0 Ma) within the Miocene used more specifically with European Land Mammal Ages. It precedes the Turolian age and follows the Astaracian age. The so-called Vallesian Crisis resulted in the e ...

(11.6-0.9 million years ago), when they entered

about 10 million years ago and became one of the major predators of this time.Antón, M., Salesa, M. J., Morales, J., & Turner, A. 2004. First known complete skulls of the scimitar-toothed cat ''Machairodus aphanistus'' (Felidae, Carnivora) from the Spanish Late Miocene site of Batallones-1. Journal of Vertebrate Paleontology, Vol. 24, Issue 4, p. 957-969. There were once also similarities between species found in North America and

Eurasia Eurasia (, ) is the largest continental area on Earth, comprising all of Europe and Asia. Primarily in the Northern and Eastern Hemispheres, it spans from the British Isles and the Iberian Peninsula in the west to the Japanese archipelago a ...

that support an immigration event from Eurasia which took place before the late Miocene, at about the end of the early

Hemphillian The Hemphillian North American Stage on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology (NALMA), typically set from 10,300,000 to 4,900,000 years BP. It is usually considered ...

(~5 million years ago). The

Old World The "Old World" is a term for Afro-Eurasia that originated in Europe , after Europeans became aware of the existence of the Americas. It is used to contrast the continents of Africa, Europe, and Asia, which were previously thought of by the ...

(Europe/Africa/Asia) species '' Machairodus aphanistus'' and the

New World The term ''New World'' is often used to mean the majority of Earth's Western Hemisphere, specifically the Americas."America." ''The Oxford Companion to the English Language'' (). McArthur, Tom, ed., 1992. New York: Oxford University Press, p. 3 ...

(North and South America) species ''Machairodus catocopis'' (now know to belong to the genus ''Nimravides'') were once though to have been very closely related, suggesting that there was a migration and that these saber-toothed cats did radiate from Eurasia into North America. This made sense based on evolutionary similarities between North American and Eurasian species as well as the immigration of other species between these two continents at this time in Earth's history. However, this was disproven with discoveries that the

were not descended from the Machairodontini and that several species of Machairodontine, such as '' Nimravides catacopsis'', Homotherium and

Amphimachairodus ''Amphimachairodus'' is an extinct genus of large machairodonts. It is also a member of the tribe Homotherini within Machairodontinae and is most closely related to such species as '' Xenosmilus'', ''Homotherium'' itself, and ''Nimravides''. It ...

were revealed to be Homotherines.

Evolutionary Relationships

Previous analysis of the

used Linnaean classification based the morphology of the upper canines, which suggested that there were four tribes within the subfamily of

. These tribes include Machairodontini, Homotherini, Smildontini, and Matailurini seen in the cladogram of Machairodontinae. Then upon finding further fossils, Machairodontini was assigned to the

tribe. The Homotherini includes species such as ''

'', ''(M. aphanistus'' and ''M. giganteus''). These species are characterized by their scimitar teeth that make up the large upper canines. The Smildontini tribe includes species such as ''

Paramachairodus ''Paramachaerodus'' is an extinct genus of saber-tooth cat of the subfamily Machairodontinae, which was endemic to Europe and Asia during the late Miocene from 15 to 9 Ma. ''Paramacheirodus'' is one of the oldest known true saber-toothed cat ...

'', ''

Megantereon ''Megantereon'' was a genus of prehistoric machairodontine saber-toothed cat that lived in North America, Eurasia, and Africa. It may have been the ancestor of ''Smilodon''. Taxonomy Fossil fragments have been found in Africa, Eurasia, and No ...

'', and

. These species have been characterized based on their longer, dagger-like teeth. The other tribe Matailurini includes species such as ''Matailurus'' and ''

Dinofelis ''Dinofelis'' is a genus of extinct sabre-toothed cats belonging to the tribe Metailurini or possibly Smilodontini. They were widespread in Europe, Asia, Africa and North America at least 5 million to about 1.2 million years ago (Early Pliocene t ...

''. These have been classified by having teeth different than the previous two clades, the long serrated teeth and the long, dagger-like teeth. Unfortunately, there are few postcranial skeletons of saber-toothed cats preserved, so available phylogenetic characters are largely cranial. New research published in 2013 took a different approach to elucidating the evolutionary relationships of

. This approach used

cladistic Cladistics (; ) is an approach to biological classification in which organisms are categorized in groups (" clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is typically shared derived char ...

phylogeny A phylogenetic tree (also phylogeny or evolutionary tree Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, MA.) is a branching diagram or a tree showing the evolutionary relationships among various biological spec ...

instead of the previous Linnaean classification. The results concluded the original four tribes could not be recovered by parsimony analysis because many of the

synapomorphies In phylogenetics, an apomorphy (or derived trait) is a novel character or character state that has evolved from its ancestral form (or plesiomorphy). A synapomorphy is an apomorphy shared by two or more taxa and is therefore hypothesized to have ...

of the saber toothed cats are based on other bones that the prominent, upper canines. Workers now recognize a clade for true saber toothed cats called Eumachairodontia that includes species from all of the previously proposed tribes: ''

'', ''

Homotherium ''Homotherium'', also known as the scimitar-toothed cat or scimitar cat, is an extinct genus of machairodontine saber-toothed predator, often termed scimitar-toothed cats, that inhabited North America, South America, Eurasia, and Africa during th ...

'' and ''

Xenosmilus ''Xenosmilus hodsonae'' (from Greek, , ''xenos'', "strange" + , ''smilē'', " chisel" ) is an extinct species of the Machairodontinae, or saber-toothed cats. Description The species name ''hodsonae'' originates from Debra Hodson, the wife of ...

''. The

synapomorphy In phylogenetics, an apomorphy (or derived trait) is a novel character or character state that has evolved from its ancestral form (or plesiomorphy). A synapomorphy is an apomorphy shared by two or more taxa and is therefore hypothesized to have ...

for the "true saber-toothed" clade Eumachairodontia is the hypertrophied, greatly flattened upper canines. The true machairodontines have a synapomorphy of flattened, small, lower canines and other bone variations such as the small upper first molar compared to basal, pre-saber toothed cats large, transversely situated upper first molar and large upper third premolar parastyle.

Morphology and Behavior

The enlarged canines of these species were not only a unique morphological trait but also were used as a specialized hunting tool. It is proposed that the effective use of the specialized canines is the canine shear-bite. This is a model that shows how the teeth would bite the prey's neck or other convex area of the body, and use the upper jaw as an anchor to pull the teeth down through the skin and create large puncture wounds for blood loss and possibly tear a significant flesh wound.Piras, P., Malorino, L., Teresi, L., Meloro, C., Lucci, F., Kotsakis, T., & Raia, P. 2013. Bite of the cats: relationships between functional integration and mechanical performance as revealed by mandible geometry. Systematic Biology, Vol. 62, Issue 6., p. 878-900. The shearing bite as mentioned above would cause less tooth breakage when used in fast pursuit. Some species within the Machairodontini show strong

sexual dimorphism Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...

, such as M. aphanistus, but other machairodonts, such as the smilodontin ''Paramachairodus'', display very slight

. The canines of the males seem to be larger than the female canines. This could be due to mate competition for females. The varied dimorphism does suggest that different species had different forms of lifestyles as how today's modern cats live.

References

{{Taxonbar, from=Q6723386 Machairodontinae Mammal tribes Miocene carnivorans Pliocene carnivorans Pleistocene carnivorans Miocene first appearances Pleistocene extinctions