Have you looked at a chimp’s teeth recently? Probably not, but if you did, you would notice that their teeth are very different from ours. Our closest primate ancestors use their teeth very differently, and as a result they have substantially different dentition. But it isn’t just other primates with teeth different from ours, our earliest human relatives had very different teeth and jaws from us because modern society has led to changes in our eating habits that affect the way our teeth develop. According to neuromuscular dentist Dr. Adam Hahn, “Our teeth and jaws develop from a complex interplay of forces, and as that interplay of forces changes, so will our teeth.”
Cooking Made Wisdom Teeth Not So Wise
One of the first changes to our teeth came when we started cooking. Before cooking people ate much of the same things as our primate relatives, which included lots of coarse, tough foods, including hard plant fibers and raw meat. But once we started cooking, our food became softer, which was great in a lot of ways, but led to the problem of wisdom teeth.
When we were eating tough food, we spent more time chewing, which stimulated our jawbone and wore out our teeth. This both gave us reason to have a third molar, and gave us a larger jawbone in which to put it. When we started cooking, we lost both the reason for the third molar and the space to put it, leading to the problem of impacted wisdom teeth.
The First Known Impacted Wisdom Teeth
Researchers recently discovered that the Magdalenian Girl, a skeleton that dates to about 13,000-15,000 years ago, was not a girl as presumed, but a woman at the time of her death. This skeleton, which was discovered in 1911 was always presumed to be that of a youth because the wisdom teeth hadn’t erupted yet, which should happen at age 18-22. However, new analysis of the bones shows she was actually aged 25-35, and the reason why her wisdom teeth hadn’t emerged was because they were impacted, according to x-ray scans of the jawbone.
This pushes back the date that people started cooking their food regularly to as far back as 15,000 years, much earlier than researchers had thought.
Knife, Fork, and Overbite
Polite society has also changed the way our teeth work. Humans used to have incisors that met edge to edge, like those of chimpanzees and other apes. Now, though, humans have developed a pronounced overbite, which most orthodontists will tell you is normal, and will try to give you if you don’t already have it. However, it turns out that this overbite is only normal if you live in a certain society and eat a certain way.
People in Europe only developed the overbite around 1800, based on the research of Professor Charles Loring Brace. Even more intriguing, the overbite started to develop in high society, then trickled down to the lower classes. What changed? In the late 1700s, it became considered polite to eat with a knife and fork at the dinner table, cutting the food into smaller pieces, then putting them on a fork to be placed delicately in the mouth. Although the fork had long been ridiculed in Europe, the Italians adopted them for eating pasta, and the custom spread from there.
The adoption of the knife and fork among Europeans can be traced with the development of the corresponding overbite, first in Europe, spreading later to America in the nineteenth century. However, in China, people developed the same pronounced overbite much earlier, by the time of the Song Dynasty, (960-1279 AD), corresponding nicely to the advent of chopsticks.
As our eating habits continue to change, so will our teeth, creating new forms that are even now developing, but we will not be able to appreciated until the far-flung future.
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