Wisdom teeth are called that because they appear between the ages of seventeen and twenty-five, an age historically associated with maturity. Aristotle wrote about late-arriving molars more than two thousand years ago, and the Latin name dens sapientiae, tooth of wisdom, reflects how long people have noticed their delayed arrival. In Japanese, one traditional explanation calls them oyashirazu, meaning unknown to parents, because they sometimes appear after children have grown up and left home. The developmental mismatch that makes wisdom teeth so problematic today involves jaw size and the number of teeth trying to fit, a tension that varies considerably between individuals and populations.
Daniel assumes wisdom teeth must make you smarter. The correction is quick and warm, and what follows moves through the ancient naming history, the Japanese name that stops Daniel mid-conversation, the biology of why wisdom teeth so often cause problems, and the carefully hedged question of whether humans are slowly evolving away from them. The episode closes on a line that reframes the tooth itself as something carrying a little piece of an older world into a very different one.
MomMom, it is a tooth that comes in at the back. My dentist mentioned I might get them in a few years.
DanielGood. And do you know why they are called wisdom teeth?
MomBecause they make you smarter?
DanielNot quite. They have nothing to do with intelligence. But the reason they got that name is actually a lovely little piece of history.
MomSo why are they called wisdom teeth?
DanielBecause of when they arrive. All your other teeth come in during childhood. But wisdom teeth don't appear until you are somewhere between 17 and 25 years old. And historically, that age was associated with the beginning of maturity and wisdom.
MomSo they are not called wisdom teeth because they make you wise, but because they arrive when you are supposed to be getting wiser.
DanielPeople have noticed their late arrival for thousands of years. Aristotle wrote more than 2,000 years ago that the last molars usually appeared around age 20. And an old Latin name became dens sapientiae, teeth of wisdom.
MomDo other languages have interesting names for them?
DanielYes. In Japanese, they are called oyashirazu, which means unknown to parents.
MomUnknown to parents? Why would they call it that?
DanielOne traditional explanation is that the teeth appear so late, sometimes after children have grown up and are no longer living with their parents. So they arrive without the parents knowing.
MomThat is the saddest and most beautiful name for a tooth I have ever heard.
DanielLanguage finds poetry in the strangest places. Now, here is the question that dentists have to answer. Why do wisdom teeth cause so many problems today?
MomBecause there is not enough room for them?
DanielExactly right. Our ancient ancestors appeared to have had more room in their jaws for these back teeth. Over a very long time, through changes in diet, development, and genetics, human jaws became generally smaller in many populations.
MomBut the wisdom teeth kept arriving anyway.
DanielBut many people still develop all four wisdom teeth, even when there is not enough room for them to erupt normally. That mismatch between the teeth and the space available is one reason wisdom teeth so often cause problems.
MomSo the teeth kept arriving, but the jaw stopped making room for them.
DanielWisdom teeth are the last teeth trying to enter an already crowded mouth. Some people have plenty of room, others do not. And when there is not enough space, those last molars can become trapped beneath the gum or grow in at an angle.
MomAnd that is when they get stuck?
DanielImpacted. Trapped sideways or partially emerged, which can cause pain and infection and damage to the teeth beside them. Dentists often recommend removing them when they are causing problems.
MomDo some people never get wisdom teeth at all?
DanielSome people never develop one or more wisdom teeth at all. Their bodies simply never make them, and it varies among different populations around the world.
MomSo are humans evolving away from wisdom teeth?
DanielMaybe. But scientists have to be careful with that idea. Not developing wisdom teeth can be inherited, and it varies as among different populations. But that does not mean we can say wisdom teeth are definitely disappearing from humanity.
MomSo they are an evolutionary leftover, in the sense that our ancestors probably got more use from them. But we cannot say evolution is definitely getting rid of them.
DanielExactly. Evolution does not make a plan and then clean up everything we no longer need.
MomSo a wisdom tooth is basically an ancient grocery bill your body still thinks it needs to pay.
DanielThat is the most creative description of a wisdom tooth I have ever heard. So Daniel, what is one thing you are taking with you today?
MomThis would have been a lot easier if my wisdom teeth were already out. But I am willing to give it a try. Wisdom teeth are called that because they arrive between 17 and 25, an age historically associated with maturity. Also, in Japanese, one traditional explanation calls them unknown to parents because they arrive after children have left home.
MomThey cause problems because of a mismatch between jaw size and the number of teeth trying to fit. And some people never develop them at all, though scientists are careful about claiming evolution is definitely removing them.
DanielA tooth named for the age it arrives, carrying a little piece of a world our ancestors lived in, into a very different one.
