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Ear Muscles

Why do we have ear muscles when most people can’t move their ears? Is this an evolutionary vestige?

Creationist anatomist Dr David Menton provides the following comments on ear muscles in answer to an enquirer to CMI-Au, 2003:

The auricularis muscles are a favorite example of evolutionists as vestigial muscle presumably left over from when we could move our ears (auricles) about like a rabbit. Clearly, the ability to orient the ears assists in sensing the stereo imaging of sound (location and distance). Not only the movement of the auricle but its complex shape and hardness on its sound receiving side appear to be used in our perception of sound. Still, people with abnormally shaped auricles (or even missing ones) still hear nearly as well. Perhaps evolutionists will declare the entire auricle to be vestigial!
There are two sets of muscles attached to the auricle, the extrinsic muscles and the intrinsic ones. The extrinsic group (outside the auricle) are the auricularis muscles of which there are three: the anterior, superior and posterior auricularis. There are several intrinsic muscles that extend from one part of the auricular cartilage to another and appear to actually modify the shape of the auricle. The ability of humans to move the auricle in a grossly noticeable way varies from individual to individual but generally the movements are slight. Are any of these movements, when noticeable or measurable, able to improve our hearing or stereo perception? None that we know of at this time.
The external auricular muscles are typically grouped with the muscles of facial expression. There are numerous such muscles in our face, scalp, neck and ears. All of the facial muscles (including the auricularis muscles) are innervated by the same cranial nerve, the facial nerve. These muscles move the skin and structures on the face such as nose lips, eyelids, eyebrows, ears etc. No other animal even approaches man in terms of muscles of facial expression. Now my wife is convinced that she sees facial expressions on our dog but, if real, they are very subtle indeed. Most animals are pretty stone faced except for lips, eyelids and ears. Some primates are capable of very stereotyped expressions but nothing like the lively face of man.
Are any of the muscles of facial expression necessary for our survival? Two that are clearly important are the orbicularis oculi and the orbicularis oris. The o. oculi is necessary for closing the eyelids. Damage to the facial nerve supplying this muscle (as may occur during a forceps delivery) will, if not corrected, result in blindness due to drying out of the cornea. The o. oris is essential for a baby to suckle. In an adult it is important for speech, eating and drinking. None of the rest of the muscles of facial expression are anywhere near as important as the two orbicularis muscles. We have facial muscles that furrow or brow, wrinkle our chin, move the corners of the mouth, wrinkle our nose, move our eyelids together, move the skin on our scalp, stretch the skin on our neck (for shaving?) etc. Different people have different abilities to move many of these muscles. Would life go on without most of the muscles of facial expression? Yes, but we would loose something of our ability to communicate with one another—often in very subtle and even subliminal ways.
Finally, a problem arises when we declare any organ to be ‘useless’ or ‘vestigial’. It is very difficult to discriminate between an organ that literally has no function and one whose function is simply not known to us. Keep in mind that there are many organs and structures in the human body that have very subtle functions, and certainly many that we can live without. I have always viewed the human body as being like the ‘Limited’ or ‘Luxury’ model of an automobile. Do you really need those headlight wipers or electric seat warmers? Probably not, but hang the cost—our body is a free gift from God.
Sincerely, David Menton

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