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Take a quick trip to the mirror and look closely at where the top of your ear cartilage meets the side of your face. Do you see a tiny, barely-there indentation that looks like a pinprick? Or maybe you’ve noticed this subtle little mark on a friend, a family member, or a newborn baby, and assumed it was just a remnant of an old, abandoned cartilage piercing.
As it turns out, that tiny hole is completely natural. It is not the result of a needle, a scar, or an accident. It is a fascinating, relatively rare congenital quirk known in the medical world as a preauricular pit (or preauricular sinus).
While it might look like nothing more than a microscopic dimple, the story behind how it gets there—and what it might mean about the ancient history of the human body—is absolutely mind-blowing.
For illustrative purposes only
What Exactly Is a Preauricular Pit?
To understand what this tiny mark is, we have to go all the way back to the womb.
A preauricular pit is essentially a minor developmental anomaly that occurs very early in pregnancy, usually around the sixth week of gestation. During this crucial period, the human face and ears are rapidly forming from structures known as pharyngeal arches. Sometimes, these arches don’t fuse together completely seamlessly. When there is a microscopic gap or a slight hiccup in the fusion of the tissues that form the outer ear, a tiny tract or sinus is left behind.
The result? A tiny hole that leads to a narrow tract underneath the skin. Some people have them on just one ear (most commonly the right side, for reasons scientists still don’t entirely understand), while others hit the genetic lottery and have them on both.
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