Putting the Bite on an Old Assumption About Human Jaws

"Human Bite Stronger Than Thought"
Human News, Discovery News (June 27, 2010)

"Humans have a much more powerful bite than previously thought, thanks to the mechanics of their skull, say Australian researchers.

Stephen Wroe from the University of New South Wales in Sydney and colleagues reported their comparison of human and other skulls recently in the Proceedings of the Royal Society B.

"'The traditional view is that modern humans have lost the ability to generate a powerful bite,' said Wroe.

"He said this has been driven by the fact that humans have relatively weak jaw muscles and lightweight skulls, compared to our fossil ancestors and living great apes.

"Some scientists argue a weaker bite evolved in response to humans eating softer foods, processing them with tools and cooking.

"But, said Wroe, there has been no direct data to support these conclusions. He said the very thick tooth enamel coating human teeth is generally associated with processing hard foods in primates...."

It's amazing, what one discovered, when experts collect and analyze data, instead of reading each other's books.

Sorry - the Lemming had a long night, and may be a bit less chipper than usual.

The article gives a little information about the human skull. Basically, we've got lighter bones and less muscle in our heads than, say, a gorilla. But they're placed more efficiently.

And the enamel in our teeth is thicker than in most primates. It better be, since between our teeth, where it counts, we're 40% to 60 % more powerful than any of the great apes. Of course, we don't have as many pounds of bone and muscle.

Still, our teeth aren't anything to sneeze at:

"...'Pound for pound we're actually biting harder than a gorilla or a chimpanzee,' said Wroe, adding there's no big difference between the bite force of a human and the nutcracker man, once body size is allowed for...."

The Lemming wouldn't recommend trying to crack walnuts with your teeth, though: Our ancestors worked long and hard to develop tools for that sort of thing.

Don't start feeling too superior to chimps and gorillas, though: they're better at chewing tough vegetable fiber. Which, considering what they normally eat, they have to do for hours - and hours - and hours.