Saber-Toothed Cat Had Weak Bite, Digital Model Says

Despite its fearsome fangs, the saber-toothed cat Smilodon fatalis may have been a relatively wimpy biter—at least compared to modern-day lions.

The prehistoric cat with the 6.5-inch (17-centimeter) chompers roamed the Americas as recently as 10,000 years ago, preying on bison, horse, and possibly even woolly mammoths.

Now computer modeling has revealed that the cat's jaws could apply only about 220 pounds (100 kilograms) of pressure, said Colin McHenry, a doctoral student at the University of Newcastle in Australia.

That's just a third of the bite strength of a lion, which can exert up to 660 pounds (300 kilograms) of force with its jaws.

The find offers new clues to understanding the hunting style of the ancient predator.

Lions, for example, can bring down their prey by leaping on them and biting their necks.

"But that would put an enormous amount of stress on the [saber-tooth's] skull," McHenry said. "So we think it had to tackle its prey before biting."

Based on the Ice Age cat's body shape, this isn't actually surprising, he added.

"People think of [the saber-toothed cat] as a lion with big teeth. But if you'd actually seen it, you'd have thought it was a bear with big teeth. [It was] built for wrestling large prey to the ground."

McHenry and colleagues at the University of Newcastle and the University of New South Wales publish their findings this week in the Proceedings of the National Academy of Sciences.

Saber-Tooth Crash Test

McHenry's team used a method called finite element analysis to simulate the stresses that would have been placed on the saber-toothed cat's skull while biting its prey.

Finite element analysis is a modeling technique developed by engineers for evaluating stresses on mechanical objects such as airplanes.

"You can think of it as a way of digital crash testing," McHenry said.
The test showed just how much pressure the saber-tooth's jaws could create before breaking the skull.

The computer model also helped reveal what the cat might have done once it had its prey down on the ground.

Paleontologists have long wondered whether the saber-toothed cat used its signature teeth to attack an animal's belly or neck.

One argument was that the cats used their fangs to eviscerate their prey, tearing into an animal's soft underside.

But attempting to hold a still-living buffalo down while biting its belly would allow the prey to thrash around enough to put dangerous pressure on the saber-tooth's jaw.

Cowboys, however, have long known that they can hold animals like buffalo down by their heads with relative ease.

And this, McHenry said, was probably what the saber-tooth did—using its long fangs to bite its prey's neck.

Modern lions actually hold prey down in a similar way. But once its prey is secure, the lion kills it with strong jaws designed to crush and suffocate.

With its weaker jaws, the saber-toothed cat couldn't suffocate its prey. Instead its long teeth would have pierced the animal's windpipe and carotid artery—killing it fairly quickly.

This might have actually been an advantage for the saber-tooth, since it can take a lion up to ten minutes to kill a buffalo by strangulation.

"That's a lot of time," McHenry said, noting that the saber-tooth had to compete with other big Ice Age predators hoping to steal its kill.

"The advantage of a quick kill seems to be quite significant."

Other scientists agree that computer modeling provides a good way of testing hypotheses about the behavior of extinct animals.

"It's important," said Mark Goodwin, a vertebrate paleontologist and assistant director of the University of California Museum of Paleontology.

Similar studies have been done with dinosaurs, he noted, such as one study that examined the cranial strength—and thus the feeding habits—of the Tyrannosaurus rex.