Why Do Humans Have Chins?

[Viva_La_Revolution]

When you think about what makes modern humans unique, the chin is probably not the first, second or even third thing that comes to mind. Yet this bony protrusion at the end of the lower jaw is not seen in any other hominid species. So what’s a chin good for? Over the years, researchers have thought up a variety of explanations for why we have chins.

http://blogs.smithsonianmag.com/hominids/2012/01/why-do-humans-have-chins/

[seabeyond]

1. i was going to joke, bet it evolved to sex and lookie....

sure enough

what a hoot.

[kristopher]

2. Isn't in the article but...

...the act of childbirth for modern humans is complicated by the size of the brain. My first instinct would be to look at the function of the chin in positioning various sized heads for passing through the birth canal.

[Viva_La_Revolution]

3. I don't think it would have any effect..

If the top of the head can 'fit', chin or chinless would make no difference. As the baby moves down the birth canal, he tucks his chin into his chest. shoulders are next, one at a time. (I've had 3.. I could go into exquisite gory detail...)

We acquired these chins after we were Homo Sapien but before homo sapien sapien.. but our whole heads changed as we became thinner, taller and more gracile, so you might be onto something there in a round-about-way.

To date, H. sapiens is the only known hominin with a high forehead, flat face, and thin, flat brows.

[kristopher]

4. May be... What mechanism causes the head to tuck?

When I look at the photo of the skull in the linked OP article the directionality of the chin in relation to the narrowest circumference of the head makes me think of the tail on a weather-vane.

[Javaman]

5. And here I thought it was all about soup. nt

[progressoid]

6. Chins are used to view computer screens