If you’ve never seen it before there are definitely people out there with a tiny, extra holy right by their ear. It’s something that’s barely noticeable and wouldn’t particularly stand out if you didn’t know what you were looking for. Surprisingly enough it’s not the remnant from an old piercing the person got when they were a kid, it’s a medical condition known as preauricular sinus. In the United States it’s estimated that only .1% of the population suffers from the condition while that number jumps to .9% in the U.K. In certain parts of Asia that number is even higher, but what is it exactly?
Preauricular sinuses are a congenital defect, meaning they can only occur while a baby is developing in the womb. While the ears are developing there’s a point where the first and second branchial arches make way for three “hillocks”, and it’s believed PS’s are an underdevelopment in this process. Preauricular sinuses are in themselves harmless and in no way damaging, but the downside is that they are susceptible to infection and can smell bad. Here’s where the surprising part comes in!
Due to the fact that all invertebrates go through this developmental process and it’s the point where fish develop their gills, evolutionary biologist Neil Shubin has theorised that preauricular sinuses are an evolutionary remnant of having gills! This theory has yet to be tested so you can’t really take it as a set in stone fact, but it’s by no means the most improbable of ideas.
Preauricular Sinus. A blessing or a curse? I’m afraid I have this. 🙁 pic.twitter.com/00HSr1uE3R
— Kiara Sapinoso (@kiarasapinoso) December 31, 2013