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Sabre-tooth’s growl was worse than its bite

Despite its fearsome teeth, the extinct sabre-tooth tiger had surprisingly weak jaws, narrowing down theories of how it killed its prey

IT HAD formidable teeth, but the sabre-toothed tiger鈥檚 bite scarcely did them justice.

Analysis of the skull of Smilodon fatalis, a heavily built cat that lived in North America until the end of the last ice age 10,000 years ago, reveals it could bite with only one-third of the force of a similar-sized modern lion.

A team led by Colin McHenry at the University of Newcastle in New South Wales, Australia, ran CT scans on a sabre-tooth skull and a lion skull. From these, they created 3D computer models of the skulls which they used to test the forces that each could endure, and inflict. A 230-kilogram sabre-tooth could bite with a force of 1000 newtons, compared to the 3000-newton bite of a 250-kilogram lion, the team found (Proceedings of the National Academy of Sciences, ).

Modern lions kill large prey by clamping their teeth around their victims鈥 throats and maintaining this bite for up to 10 minutes, slowly suffocating the struggling animal. As a result, a lion鈥檚 skull must withstand huge forces. 鈥淲hen the Smilodon model was exposed to these forces, it lit up like a Christmas tree,鈥 revealing intolerable stresses that suggested it could not contend with flailing prey.

McHenry reckons the beefy sabre-tooth probably killed large animals by wrestling them to the ground and pinning their head, before making a deep killing bite to the throat.