Darwin's tubercle
Also called: Darwin's point · Auricular tubercle · Tuberculum auriculae
A small bump on the folded rim of the ear, which Darwin thought was the leftover tip of a pointed ancestral ear. Between 10% and 58% of people have one, depending on the population.
How common
Do you have this?
How it works
The outer ear is a sheet of cartilage covered in skin. Its folded outer rim is the helix. In some people the helix has a small thickening on its upper back edge, where the upper third meets the middle third1. It looks like a tiny point or knot. It can be on one ear or both, and it varies from a barely visible ridge to a clear bump.
It is thought to form before birth, when the ear rim folds in unevenly. The exact process is not known4. It was once thought to be passed down in a simple dominant pattern, but family studies question this4. Chance events during development may matter more than genes1.
How common it is
The two commonly cited figures come from single studies, not a worldwide survey, one in Spanish adults and one in Swedish schoolchildren1. Different age groups, different populations, and different rules for what counts as a visible bump all feed into the gap between 10% and 58%. No study has combined multiple populations into one estimate, and it is not known whether the tubercle becomes easier or harder to spot with age.
Try it
- Look at your ear in a mirror, or feel it with a finger.
- Follow the folded rim from the top of the ear down and back.
- Feel for a small thickening on the inside edge of the rim, roughly a third of the way down.
- Check the other ear. Many people have it on one side only.
Is it a problem?
No. Darwin’s tubercle is a harmless variation in ear shape4. It is not known to cause any illness, and there is nothing to check with a doctor because of it alone. It is present from birth1.
History and culture
Charles Darwin described the bump in The Descent of Man in 187112. He credited the sculptor Thomas Woolner with pointing it out to him1. Darwin argued that it was the folded-over tip of the pointed ear seen in some monkeys, and so a trace of human ancestry1. It is still listed as a vestigial feature3. Among monkeys, macaques and baboons have a similar pointed upper ear margin4. Fiction gives pointed ears to elves and Vulcans. Darwin’s tubercle is the closest a normal human ear gets.
Sources and further material
- Wikipedia Darwin's tubercle
- Wikipedia The Descent of Man, and Selection in Relation to Sex Darwin, 1871. The book that first described the tubercle.
- Wikipedia Vestigiality
- NCBI Darwin's Tubercle: Review of a Unique Congenital Anomaly Loh & Cohen, Dermatology and Therapy, 2016. A review of the history, prevalence and clinical features.
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