Why Do We have Chins?

Humans are strangely obsessed with how they look, and when we talk about looks, the first thing that typically pops up is someone’s face. Although there is the whole rest of the body too, the face is often the predominant factor when considering someone’s appearance.

Primitive Hypotheses

George Clooney is well known for having a distinct, “powerful” chin. It’s not only him, either, many people have chins that other people would long to have. However, why do we have a chin in the first place? Does it have any specific purpose or is it just there?

In the past, there were many hypotheses about chins and the purpose of their placement on the bottom of the human face. One hypothesis that became very popular – and subsequently accepted – was that humans have chins to support the forces that our face experiences while we chew our food.

Lately, however, this theory has been debunked. “The development of the chin doesn’t seem to have anything to do with resistance to bending stresses,” said Nathan Holton, an anthropologist at the University of Iowa.

Chins: A Study


To ascertain the reason we have chins and disprove the above assumption, Holton examined X-ray images from the Iowa Facial Growth Study using measurements from 18 females and 19 males. He tracked jaw development and bone distribution, which are said to play a vital role in protecting against various types of stresses that a human face experiences.

It is true that chins become more prominent as a person ages, but researchers didn’t find any link between chin development and force resistance. Interestingly, Holton also said that jaws are better at resisting certain types of forces at the age of 3 as compared to adult jaws with a fully-developed chin.

Why Do We Have Them?

Ever since the jaw-protection hypothesis was nullified, a concrete reason hasn’t been found for the existence of chins on human faces. However, Holton is of the view that the Homo genus (which includes humans, Neanderthals, and our other ancestors) have evolved in such a way that their faces have generally become smaller.


Humanoid faces have become smaller over time and the lower portion of the face is the last to stop growing, which is why this part looks more prominent and long as we age. This is also why we have a ‘chin’, since it simply doesn’t stop growing. It’s an evolutionary lag.

Our faces becoming smaller than our distant ancestors is one of the most important reasons for chins.

Why Have Our Faces Shrunk?

The older Homo species were used to living in the wild, so their bodies were adapted based on those conditions. As time passed, humans became more ‘domesticated’, meaning that there were fewer encounters with unpredictable conditions of nature and dangers of the wild. This resulted in hormonal changes associated with reduced violence and stress on the body. As the overall size of the body decreased, the nasal cavities did not have to grow much to let in more air to ensure the survival of the body. As a result, the face did not have to grow as much to support what would have been a bigger nose.

‘Thus, noses became shorter and chins slowly came into existence,’ says Holton.

Did you ever suspect that the shrinking of your face might be the reason behind your chin?

I doubt you did… it certainly never crossed my mind!


  1. Wikipedia
  2. Live Science
  3. Why Do Humans Have Chins? – Smithsonian.com
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About the Author:

Ashish is a Science graduate (Bachelor of Science) from Punjabi University (India). He spends a lot of time watching movies, and an awful lot more time discussing them. He likes Harry Potter and the Avengers, and obsesses over how thoroughly Science dictates every aspect of life… in this universe, at least.

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