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The Evolution And Science Behind Wisdom Teeth

Why do humans have wisdom teeth? What is so wise about them?

An xray of a person's mouth

Photo: Jason (Flickr)

When wisdom teeth crowd the mouth they must be removed.

As we all learned in health class, human beings have 32 teeth.

Twenty-eight of them come in before puberty, but the last four teeth, our “third molars,” usually come in during our late teens or early twenties, when we’re presumably older and wiser hence their nickname, “Wisdom Teeth.”

Why Do We Have Wisdom Teeth?

These extra molars probably helped our early ancestors to chew and digest their rough diet of tough meats, fibers, and seeds. These wisdom teeth would have helped early humans to eat better, and in turn, live longer in better health.

According to the logic of evolution, the teeth would have given our ancestors an edge in surviving long enough to reproduce, so evolution has passed them along to modern humans.

Why Get Them Removed Today?

But, if these extra teeth were such an advantage for our ancestors, then why do most people today need to have their wisdom teeth removed? Again, the answer lies in evolution.

As we humans have evolved, our skulls have become slightly smaller, while our brains have actually become a bit larger. To make room for these changes, our jaws have moved lower and further back on our skulls, and in the process, our jaws have become shorter.

Less Room, Less Teeth

Early humans had longer jawbones which provided enough room for all 32 teeth. Most humans today have smaller jaws that can’t accommodate the four extra teeth.

When there isn’t enough room for the teeth, they become “impacted” stuck, in other words and many of us have to have them surgically removed.

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  • Luther Towler

    Well, if evolution is to blame, then we really can’t do anything about it, can we? LOL! So, does this mean that our ancestors had less dental problems than us? I mean, if their jaws were more spacious, then they probably didn’t have crooked teeth and impactions.
    - Luther Towler

  • Anonymous

    I would also surmise that until recently, poor dentasl hygeine would result in tooth loss that could be replaced by wisdom teeth.  Now that all water is flouridated and we brush daily, no room for those wisdon teeth, whereas before they could replace lost teeth.

  • MotherGinger

    Wrong. Research Weston Price. Google ancient skulls. They had almost all their teeth, almost zero cavities, and plenty of room for all 32 of their teeth.

  • MotherGinger

    This is absurd. Our skulls have become larger, to make room for bigger brains, in just the last 100 years? You give evolution a bad name. Go look at some skulls from the 18th century (or any prior) anywhere in the world. Virtually all had plenty of room for their wisdom teeth without need for extraction.

    We don’t have room for wisdom teeth today because OUR DIETS ARE DEFICIENT in vitamins A/D/K2 thanks to processed industrial oils replacing butter, and the modern lack of foods such as liver and fish eggs in our diet. Our palates have narrowed because of that, many so narrow that they don’t have room for the next 4 molars either. This is a deformity, not an adaptation.

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