Evolutionary History of Saber-Toothed Cats Based on Ancient Mitogenomics

This study recovered complete mitochondrial genomes from the dirk-toothed Smilodon and the scimitar-toothed Homotherium, allowing a genetic test of how these iconic sabertooths relate to one another and to living cats. The analyses showed that the machairodont sabertooth lineage diverged very early from the ancestors of all modern felids, roughly twenty million years ago, and that Smilodon and Homotherium themselves split deep in the Miocene, long before their Pleistocene heyday. By placing the sabertooths firmly outside the radiation of living cats, the work confirmed that the machairodonts were a distinct and ancient branch of Felidae with no surviving descendants. It stands as a landmark in sabertooth palaeogenetics, demonstrating that ancient DNA can resolve relationships among long-extinct predators.