The extreme teeth of sabre-toothed predators were 'optimal' for biting into prey

Why sabre-toothed animals evolved again and again

Study: Saber-Toothed Predators’ Teeth were Highly Effective at Puncturing Prey

World's oldest mammalian ancestor discovered in Mallorca. It is the oldest known gorgonopsian on the planet, the lineage of saber-toothed predators that would eventually give rise to mammals.