There isn’t much of a consensus on this. Some people think it’s due to greater muscle dexterity on one side of the face, others say one eyebrow is dominant in the way that one hand is dominant, while others argue that there’s a genetic component to it.
It might be a combination of all three of these factors, or perhaps none of them at all – there’s no definitive answer, unfortunately. However, if it’s a skill you’d like to improve, with a bit of practice, you can apparently learn to raise both eyebrows independently.
Read more:
- Why do we have eyebrows?
- Why does only one nostril get blocked when you’re sick?
- Why does plucking your eyebrows make you sneeze?
- Here’s why nasal and ear hair become more prominent as you get older
Asked by: Jennifer Bruce, via email
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