Comments on: Who are you calling weak? Human jaws are surprisingly strong and efficient

By: Stephen Wroe

Stephen Wroe — Fri, 20 Aug 2010 19:10:56 +0000

The simple answer is yes – humans are entirely capable of inflicting truly terrible damage on other people by biting. There are hundreds of well-documented cases in the medical literature – noses, eyes, cheeks torn out – and even instances of human bites breaking through the bone of other humans. If you don’t have time to trawl through the literature then just ask any surgeon woring in emergency at a large metroplitan hospital.

And to make it worse still – human bites are particularly likely to lead to serious infection.

By: Steve

Steve — Tue, 13 Jul 2010 01:23:56 +0000

Anyone remember Charla Nash, whose face was bitten off by a pet chimp in Feb. 2009? She lost both eyes and her nose and portions of her jaws, which are now slowly being rebuilt by her surgeons. Is the human jaw even remotely capable of inflicting such damage?

By: jdmimic

jdmimic — Wed, 23 Jun 2010 17:39:34 +0000

While his data are certainly intriguing, I wouldn’t say that it necessarily creates a fatal flaw in all the earlier hypotheses. Two things to consider here; one, size does matter to an extent. When scaled to size, humans have the strongest bite force comparatively. But at actual sizes, we don’t. Absolute strength is still not as strong in the humans. When one is trying to break a rock, one doesn’t care that a smaller hammer may be proportionately stronger if it doesn’t have the absolute power to do the job.
The second thing to consider is that, while the jaws may have evolutionarily gotten more efficient, they also appear to have gotten less capable of sustained activity, as they point out in the paper. This would seem to indicate that our dietary habits have shifted towards food that is more nutritious bite for bite, thereby reducing our need for prolonged chewing.
I do find it interesting that it appears the efficiency developed by distributing the stress farther along the jaw, rather than concentrating it along the joint. The data does not create a “fatal flaw” in the hypotheses, but it does require the arguments to become more nuanced to address the new data.

By: southlakesmom

southlakesmom — Wed, 23 Jun 2010 10:02:39 +0000

Interesting thoughts…my son just finished orthodontia to correct a bite. I wonder if the consistent misalignment that pays for many orthodontists to vacation in warm places is unique to humans. Do the other species mentioned “suffer” from similar problems? Of course, a misaligned bite will affect strength as well.

By: Ian Tindale

Ian Tindale — Wed, 23 Jun 2010 06:28:17 +0000

But look how weak our orbits around our eye sockets are, though.

And what’s the point in a diagram that labels the items a) b) c) d) etc. on two rows, then the legend refers to it as “from left to right”. Come on, one or the other!

By: Nathan Myers

Nathan Myers — Tue, 22 Jun 2010 23:37:02 +0000

I’m used to reports of bite force of megalodons, tyrannosaurs, pliosaurs and mosasaurs measured in terms of what it takes to bite through a Yugo or a Hummer. I suppose for primates we need to use milli-Yugos.