You know about your eyes, your ears and even the insides of your mouth. But the one thing that rarely gets into your notice is the lowest part of your face. That forward pointed part which is below your lower lip or lower jaw often does not intrigue your curiosity to dig deeper for it. But just like our other body parts are embedded with some facts and secrets, our CHINS too hold some of the major features and functions that are left unheard by the people.
Have not some of you ever wondered about the size, function, reasons for humans to have chins? Do only humans have chins or others too? Which segment in any creature’s face would be called as chin? I will try to handle all such queries of your curious mind in this article.
Okay, to begin with, the size of human chins.
Chin size in humans can vary between 0.7 to 11 cm. What? Such a huge difference? Just imagine someone with 0.7 cm of the chin and then think about someone with that higher end of 11 cm of the chin. Well, 0.7 cm size of chins is for small children as their bones and skulls are not developed completely and persist in a nascent stage. As they grow, their chins’ size can go up to 11 cm of width.
How our chins have evolved?
Presence of a well-defined chin in our facial features is a prominent part of the modern human body. We differ from our ancestors in appearances on many grounds, well-chiseled chins being one of them. Scientists came to know about this fact after the study of skulls and fossils of our ancestors. Scientists point towards the shortening of our dental arch and evolution of our tooth row arrangement along with the change in feeding habits of humans as to be the reasons for the difference between our chins and our ancestors’.
Why do we have chins?
What was the need for this extension in the lower part of our face? The answer to this lies in the functions that your chin got to perform, which are :
1. Helps our jaws: Chins, as debated in many of the findings, support our jaws. Chins tend to help the jaw to stress less by supporting it. Chins protect jaws from bending or stooping down which otherwise would have dropped down because of our facial structure.
2. Helps in chewing: Chins have a critical role to perform in mastication or you can say in chewing. As chewing produces a great deal of force on our muscles of the lower face, chin bears some of the muscle load or force to keep the chewing process going unhindered. There are several muscles in our chin to keep holding the jaw in its position.
3. Helps in speaking: Have you ever tried to talking or speaking while tucking in your chin or lower jaw in your chest? If not, then do it once and you will get to know how it feels. Try to speak in that position. You will feel pressure and force on the side muscles of your neck. That is why we humans have chins to help us in uttering words effortlessly.
4. Attraction function: There is a difference between the shape and size of a male and female chin. Males have longer and wider chins while females tend to have more round-shaped chins. This difference, biologists say, would not have been there if there is no relation to the attraction of the opposite gender.
But opposite to this Double-chin can make a person averse to look at you. Double-chin? Yes! People get double chins because of their lazy lifestyles. It is the formation of a chin like structure, entirely made up of muscles; below your chin which gives the appearance as of a person has double-chin. And such a double chin does exactly opposite to what a sharp chin may do, i.e., make you look obese.
That all goes for humans, from chewing to speaking. But, what about other living beings of the animal kingdom? They do not need to speak with each other to communicate. So, do they have chins? The clear answer is NO! You must have cuddled your pet dog or cat by stroking its chin with your fingers. But that is not its chin. To understand this read the definition of chin again which is mentioned in the very beginning. It is not just a part below your jaw but a bony protrusion which seems like a bit lump structure in human skull X-ray. But if you see skull X-rays of other animals, be it your pet, or others they don’t have such a lump. It’s just their lower jaw that you rub which loving them. You would be surprised to know that even apes and chimpanzees, which are considered to be closest animal species to humans evolution, do not have chins either. Their lower jawbones are bent inward but not outward like humans.
Okay, these all were the “FOR” side of having chins; but, there are tall claims from many scientists themselves that chins are useless in humans. Their arguments? Stated below:
1. The biggest function of chins which is to help us while eating is being undermined by these scientists. Do they argue that if eating puts such force on our mouth while chewing then why do apes and chimpanzees have chins? These animals have extra tissues and extra muscles in the inner area of their mouth and jaws rather than outer. This explanation seems to be more logical to them rather than having extra bones outside just like human chins.
2. Do chins help us in speaking? Some researches assert its answer to be a “NO”. This is because we don’t feel a lot of pressure of force while speaking and so we don’t need any support. Even if needed, the support should have been of muscles near the tongue not outside the mouth.
3. For chins’ function of sexual attraction, it is said that if chins were some feature to attract the opposite gender then it must have been present only in one gender and not both. But in humans, all of them have chins; which is why we cannot ultimately relate chins to be the basis of choosing a partner.
If we consider the earlier mentioned points, then we will be convinced that chins sit on our faces for many reasons but the statements stated later in the article again bring us to the same position as we started from; the question of do we need to have chins? Well, there is no clear “YES” or “NO” answer to this. But if you are a person who finds others to be attractive or unattractive on basis of sharpness of chin then you might go with the former explanations; otherwise, the later arguments serve your purpose of considering chins as redundant human face feature.