Like the appendix, wisdom teeth are a somewhat mysterious part of the human anatomy. They don’t appear to serve much of a purpose — unless you count trips to the doctor and reasons for expensive, unpleasant medical procedures. According to the New York Times, millions of young people living in the United States have their wisdom teeth extracted every year, usually to prevent problems later on in life.
A new study published in the Proceedings of the National Academy of Sciences sheds light on why human beings have wisdom teeth and why they cause us grief. The culprit seems to be the evolution of the human diet. Physical anthropologist Noreen von Cramon-Taubadel looked at skull specimens from 11 populations around the world and compared those groups that obtained their food through hunting and gathering with those whose diet was based on agriculture. She found that the hunter-gatherers had longer, narrower jawbones that were well-adapted for chewing hard substances — and roomy enough for wisdom teeth. The latter group, which ate more starches and cooked foods, chewed less and developed shorter, smaller jaws with less space for an extra set of molars.
This is yet another intriguing example of how culture and human biology intersect. And since those of us living in the post-industrial era are unlikely to give up our cereal and mashed potatoes, it seems we’ll just have to resign ourselves to our time in the dentist’s chair.
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