Bodily Oddities

Tongue rolling

Also called: Tongue curling · U-shaped tongue

Between 65% and 84% of people can curl the sides of the tongue up into a tube. For decades it was taught as a simple one-gene trait. It is not.

Mouth and throat Muscle Trick Voluntary
Try it Learnable Debunked myth Genetic

How common

65–84% of people Very common · > 50% A Dutch study of 387 people found 83.7%.

Can you do this?

These are answers from visitors, not a study.

How it works

The tongue is a block of muscle with no bone inside it. Four pairs of muscles inside the tongue run lengthwise, crosswise, and up and down2. Rolling uses them to lift both side edges until the edges meet in the middle. The tongue becomes a tube. You can blow air through it.

Between 65% and 84% of people can do this1. A Dutch study of 387 people found 83.7%1. The figure varies between populations.

In 1940 the geneticist Alfred Sturtevant reported that rolling is a dominant trait controlled by a single gene13. School textbooks copied the claim for decades. It is wrong. Studies of identical twins, who share all their genes, found that between 21% and 28% of twin pairs did not match1. More than 20% of children learn to roll their tongue between the ages of 6 and 121. Sturtevant later called his original claim embarrassing3. Genes probably play a part. They do not decide the result on their own.

Try it

  1. Open your mouth and push your tongue out a little.
  2. Try to lift both side edges of the tongue toward the roof of your mouth.
  3. If the edges meet, you have a tube. Blow through it to check.
  4. If nothing happens, practise in a mirror for a few minutes a day. Some people find the movement after a week or two.

History and culture

Tongue rolling is still used as a classroom example of inheritance. Many genetics teachers now use it as an example of how a simple story can be wrong1.

Sources and further material

  1. Encyclopedia Tongue rolling Prevalence figures, twin studies, and the history of the one-gene claim.
  2. Encyclopedia Tongue Anatomy of the intrinsic tongue muscles.
  3. Encyclopedia Alfred Sturtevant The geneticist who published the 1940 claim and later called it embarrassing.
  4. Video Tongue rolling demonstration YouTube search.
Mouth Trick

Cloverleaf tongue

Folding the tongue into three lobes, like a clover leaf. Between 10% and 15% of people in Western samples can do it. It is usually called the hardest tongue shape.

10–15% (Western samples)
Mouth Trick

Tongue folding

Folding the tip of the tongue backward over itself inside the mouth. Between 14% and 27.5% of people can do it.

14–27.5%
Mouth Trick

Tongue twisting

Turning the tongue on its side so the edges face up and down, or all the way over. Between 12% and 36% of people can twist it at least halfway.

12–36%
Mouth Trick

Pointed tongue

Making the tip of the tongue narrow and sharp, like a pencil point. About 55% of people can do it. After rolling, it is the most common tongue trick.

~55%