Dental functional morphology in the marsupial sabre-tooth Thylacosmilus atrox (Thylacosmilidae) compared to that of the felid sabre-tooths.

Abstract

The South American Middle to Late Pliocene fauna of Argentina included the borhyaenid marsupials Thylacosmilus atrox and Notosmilus pattersoni, the latter known only from a single Late Pliocene occurrence. Thylacosmilus atrox has been interpreted as a marsupial with a carnivorous specialisation convergent on the fissipede and machairodont sabre-tooths of Eurasia, Africa and North America. Thylacosmilus atrox superficially resembles placental sabre-tooths in general conformation but also shows remarkable divergences, some of which are attributable to its marsupial ancestry.