|MadSci Network: Evolution|
The most obvious use of the earlobe in man is for piercing and holding earrings. Earlobes seem to have a much longer history for piercing than other parts of the anatomy although the growing practice of piercing other parts of the anatomy seems to be surpassing the use of the earlobe! It is unlikely that we evolved the earlobe for purposes of piercing. In reality, there is no known biological function associated with the earlobe in man. This small piece of flesh does have a prominent blood supply but it does not contain cartilage like the other parts of the external ear. The most obvious difference among humans is that the lobe is attached to varying degrees to the side of the face. Some of us have an earlobe that is more like an appendage while in others the lobe is more directly attached. Some muscles attached to the external ear in humans seem vestigial in terms of evolution. Some of us can wiggle our ears, some of us cannot. In lower mammals, dogs for instance, these muscles allow exquisite control of the external ear for purposes of moving them to better able to detect where sounds originate. In some aquatic animals, the little tab of skin in front of the ear canal, called the tragus, can be operated to act as a valve to open and close the ear canal. However, the earlobe itself has no known biological function.
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