Promegantereon and Paramachairodus for example, were likely arboreal or at the least, scansorial, 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, a later species, was more intermediate in physiology between these earlier forms and the more cursorial Rhizosmilodon and Smilodon itself, which were better built for life on ground, as well as bringing down relatively larger prey.

[3] The phylogenetic relationships of Smilodontini are shown in the following cladogram:[4][5][6][7][8] †Megantereon cultridens †Megantereon ekidoit †Megantereon whitei †Megantereon hesperus †Megantereon inexpectatus †Megantereon microta †Megantereon nihowanensis †Megantereon vakhshensis †Smilodon gracilis †Smilodon fatalis †Smilodon populator †Rhizosmilodon fiteae[9] †Paramachairodus maximiliani †Paramachairodus orientalis †Paramachairodus transasiaticus †Promegantereon ogygia[10] 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.

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.