Anatomy, Head and Neck: Eyelash

Excerpt

The Greek word for eyelid is “blepharon,” from which is derived the prefix "belpharo," which has been in use since antiquity. The Greek for an eyelash is “blepharida” which is not used in medicine today. The Latin for eyelid is “palpebra” and that for eyelash is “cilium” a word only in use since the early 18 century.

Eyelashes and eyebrows are important anatomical structures which are central not only in the face but central to all perceived human interactions. Eyebrow movement conveys emotions (sad, happy, angry, surprise, pensive, etc.) and eyebrows protect the eyes by relaxing the “curtain rods” that they effectively are when tired, thereby relaxing the upper eyelid skin and contributing to lid closure and eye protection. Eyebrow hair direction serves to protect the eyes from particulate matter and sweat.

Eyelashes and eyebrows have always been an essential part of facial beauty. They have been plucked, accentuated and modified in innumerable ways to enhance the beauty of the face and eyes in particular in many cultures. The Egyptians and the Indians have used materials like kohl to enhance brows and lashes for centuries. The emphasis of the eyes manifests in the modern world through the use of mascara, eyeliner, and eyeshadow. Curlers are used to exaggerate the natural curve of lashes. Although long lashes are prized in most cultures, certain cultures (the Hazda, the last of the hunter-gatherer tribes of Tanzania) trim their lashes.

Comparative Anatomy

Mammals have eyelashes; some, like the camel, have profoundly long lashes, long used to accentuate features in cartoons. Cows have long straight lashes which are medially oriented. A description of “cow lash deformity” is used when seen as a complication of blepharoplasty, often affecting the lateral third of the upper eyelid. Other large mammals like horses also have similar long, relatively straight lashes.

The eyelash viper is said by some in South America to wink after striking its victim. The “lashes” are not lashes, but modified scales above the eyes. And, of course, snakes cannot wink as they have no eyelids!