Machairodontinae

Machairodontinae is a subfamily of extinct saber-toothed cats within the family Felidae. Members of this group are characterized by elongated upper canine teeth, which in many species formed long, blade-like blades. The subfamily includes several well-known genera, such as Smilodon, Homotherium, Megantereon, Machairodus, Amphimachairodus, and related forms. They inhabited a broad geographic range that included Europe, Asia, Africa, and the Americas, and they lived from the late Miocene through the end of the Pleistocene, roughly 16 million to about 10,000 years ago.

Anatomically, machairodontines typically had robust skulls and powerful forelimbs, adaptations suitable for grappling and restraining prey. Their teeth and jaws were specialized for delivering precise, fatal bites with their long canines, while the carnassial teeth remained important for processing flesh. The exact hunting method remains debated, but many reconstructions depict ambush predation in which the predator used its claws and forelimbs to seize prey and delivered a decisive neck or thoracic bite with the saber-like canines.

Taxonomically, Machairodontinae is divided into two major lineages: Smilodontini, which includes longer, dagger-like canines and genera such as Smilodon and Xenosmilus; and Homotherini, which features relatively shorter, flatter canines and includes Homotherium. The two groups display differences in limb proportions, dentition, and habitat preferences, reflecting varied ecological strategies within the same subfamily.

Extinction of machairodontines occurred by the late Pleistocene, with last populations disappearing around the end of this epoch. Factors in their decline likely included climate change, habitat shifts, and competition with other predators and early humans. They are known solely from fossil remains and are studied for their distinctive dental and skeletal adaptations that set saber-toothed cats apart from modern Felidae.