Why do we have wax in our ears?
Earwax – it’s on the list of slightly revolting things most of us would rather not think about.
And all going well we don’t really have to pay much attention to the secretions our ears produce.
In fact, much of the time we are unaware of it, unless a build-up affects our hearing.
So why do we have earwax in the first place? Glands in the outer ear canal produce a substance called cerumen, to help moisturise, clean and protect.
The concoction of fatty substances and other molecules gets mixed in with shed skin cells to form what we see as the waxy stuff, and it can protect our hearing equipment from irritants.
It does this by trapping particles like dust that waft in and get caught in its stickiness.
It may also contain biochemicals to address potentially problematic microbes.
Earwax has become somewhat feted among geneticists, because whether you have wet or dry earwax can be tracked back to a single “letter” in a single gene (ATP-binding cassette C11), making it easy to identify from your DNA.
In general, people of East Asian heritage tend to have dry or flaky earwax, while people of African or European descent are more likely to have wetter and gloopier ear secretions.
A recent paper in Molecular Biology and Evolutionfound that particular genetic variants link in with latitude, and suggests that climate may have had an impact on how earwax genes spread out.
