You might have noticed that a few people have a barely noticeable hole where the top of their ear cartilage meets their face. Believe it or not, it’s probably not the remnants of an old piercing they had when they were 15.
Just 0.1 percent of the population have it in the US, 0.9 percent in the UK, and as many as 4 to 10 percent in Asia and parts of Africa, according to one study. In South Korea, that figure could be as high as 5 percent, and it’s most common in people of African or Asian descent.
It’s actually a congenital disorder called Preauricular sinus. Although harmless in itself, it can be susceptible to infection. It is caused by the first and second pharyngeal arches. This is a structure found in all vertebrates that occurs during embryonic development. Simply put, the little holes are ‘nodules, dents, or dimples’ that are exposed anywhere around the external ear – usually where the face and cartilage meet.
The preauricular sinus is a hereditary birth defect that was first documented by a scientist called Van Heusinger in 1864, and while they’re usually only found on one ear, up to 50 per cent of people have them on both.
In mammals, they go on to form the structures of the head and neck, but in fish they also help develop into their gills. The cause isn’t known but Business Insider reported that evolutionary biologist, Neil Shubin, theorised they could be an ‘evolutionary remnant of fish gills’ Of course, that’s currently a theory that hasn’t been scientifically tested.
But nevertheless, when you think that we still have tailbones, goosebumps, and appendixes from our evolutionary forebearers, it’s certainly not impossible.
If you’re part of the small percentage of people who happen to have these tiny fish gill-like holes, don’t worry – as already stated, they’re harmless. And no, you can’t breathe underwater if you have them. The only complication that may occur is the odd infection which is easily treatable with antibiotics.