A feline-like predator that stalked through South America millions of years ago had huge fangs, but modern day house cats have a much stonger bite.
Thylacosmilus atrox, had teeth extending so far inwards that they almost went into the ancient feline's brain. The animal "looked and behaved like nothing alive today," said palaeontologist, Dr. Stephen Wroe who led the study, according to a University of New South Wales press release.
"To achieve a kill the animal must have secured and immobilised large prey using its extremely powerful forearms, before inserting the sabre-teeth into the windpipe or major arteries of the neck - a mix of brute force and delicate precision," he said.
The Thylacosmilus atrox is one of the best preserved examples in the evolutionary line leading up to the sabre-tooth tiger; it had much larger teeth than its later cousin.
The sabre-tooth had a strong neck which could have helped propel the animal into its prey, Thylacosmilus atrox could have possessed similar features.
"We found that both sabre-tooth species were similar in possessing weak jaw-muscle-driven bites compared to the leopard, but the mechanical performance of the sabre-tooths skulls showed that they were both well-adapted to resist forces generated by very powerful neck muscles," said Dr. Wroe.
Wroe believes the Thylacosmilus atrox could have been even more extreme than the Smilodon (sabre-tooth).
"Frankly, the jaw muscles of Thylacosmilus were embarrassing. With its jaws wide open this 80-100 kg 'super-predator' had a bite less powerful than a domestic cat. On the other hand - its skull easily outperformed that of the placental Smilodon in response to strong forces from hypothetical neck muscles," he said
Wroe also noted the Thylacosmilus atrox's teeth were extremely fragile and prone to damage. The neck muscles on the ancient mammal could have made up for its disadvantages, allowing for a quick kill.
"Big prey are dangerous - even to super-predators - and the faster the kill the less likely it is that the predator will get hurt - or for that matter attract unwanted attention from other predators. It may not have been the smartest of mammalian super-predators - but in terms of specialization- Thylacosmilus took the already extreme sabre-tooth lifestyle to a whole new level," said Dr. Wroe.