Remember how Priya Prakash Varrier with her dancing eyebrows winked her way into our hearts and became an overnight internet sensation! Eyebrows and expression have a long association and are invalable assets for the exponents of our classical dance forms - Bharatnatyam, Kathakali, Kuckipudi and Mohiniattam.
We Plastic surgeons have been bothered about the eyebrows for a very long time as drooping eyebrows make the face look aged and nice arching eyebrows signify youthfulness. So in our eternal quest of rejuvenation we have been working in and around the eyebrows since quite some time. It was only when we started replacing missing parts of the eyebrow did we realize that each one of them comprises of three sections – head, body and tail and the body has two halves upper and lower and all four of these parts i.e. head, upper body, lower body and tail, have hairs growing in different directions!
If
you compare modern human beings to our prehistoric ancestors, one of the most
obvious physical differences you'll find is the lack of a massive brow ridge.
Over time, human evolution led to us developing finer facial features, smoother
foreheads, and eyebrows. But why did this happen?
A
recent study, published in Nature Ecology and Evolution claims that eyebrows
that are mobile help people with non-verbal communication, which is one of the
traits that make us the most advanced human species to ever exist. In contrast,
the Neanderthals' jutting brow was used for displays of dominance and sexual
attraction instead, similar to the function of a stag's antlers.
"Sexually
dimorphic display and social signaling is a convincing explanation for the
jutting brows of our ancestors," said Paul O'Higgins, senior author of the
study and professor of Anatomy at the University of York. "Their
conversion to a more vertical brow in modern humans allowed for the display of
friendlier emotions, which helped form social bonds between individuals".
Around
100,000 years ago, human groups began to diversify their social networks, which
is why it made evolutionary sense to prioritize emotional responses over
violent adaptations. Scientists claim that it is around this point in history
that human being began to develop smaller and flatter brow ridges, as well as
the mobile eyebrows that we still have today.
Eyebrow movements
allow us to express complex emotions as well as perceive the emotions of
others. A rapid "eyebrow flash" is a cross-cultural sign of
recognition and openness to social interaction and pulling our eyebrows up at
the middle is an expression of sympathy. Tiny movements of the eyebrows are
also a key component to identifying trustworthiness and deception. On the flip
side, it has been shown that people who have had botox which limits eyebrow
movement are less able to empathize and identify with the emotions of others.
But why do we have
them in the first place? Is it only to communicate through our expressions? The
consensus seems to be that eyebrows keep moisture, like sweat and rain, from
running down a person’s forehead straight into the eyes. This explanation is
easy to visualize when you look at the morphology and facial features involved
— most notably, the pronounced slant of the eyebrow hairs which directs water
away from the eyes. This has obvious evolutionary survival advantages. Sweat
tends to be very salty, and salty liquids getting into your eyes while you’re
running in an African Savannah would be a severe hindrance to hunting. It could
also be a potentially deadly problem when the tables are turned and you are
fleeing hungry predators. Eyebrows give those potentially deadly distractions a
detour to the side of the face, instead of right into your eyes.
Beauticians have been
dabbling with the eyebrows since ages. According to them there are six facial
shapes - Oval Face, Round Face, Long Face, Square Face, Heart shaped Face , Diamond
shaped Face and there is a best eyebrow shape suited for each facial shape!
Party heart-throbs, brides and cine-artists have all had special attention paid
to their eyebrows to make them look more beautiful and sexy. What they as for can
then do with this ammunition, only sky is the limit!
Geneticists have
established that the shape, color, and thickness of your eyebrows are inherited
traits. In one major study in 2015 ( https://www.nature.com/articles/ncomms10815
), scientists found a strong relationship between inheritance of specific genes
and eyebrow appearance. Four separate genes may affect eyebrow hair texture,
one gene may determine eyebrow shape, five genes affect eyebrow hair color, and
one gene determines whether or not you develop a monobrow. But, environmental
factors also have a lot to do with how your eyebrows look. Years of waxing or
tweezing your eyebrows can permanently affect their shape. Injuries to the skin
near your eyebrows can also affect hair growth and eyebrow shape.
Just as eyebrow
characteristics are inherited, so are abnormalities affecting the eyebrows. One
of the most common abnormalities affecting eyebrows is madarosis, or loss of
eyebrows. The term madarosis can also refer to loss of eyelashes. This can be
caused by many different inherited disorders. Several congenital facial clefts
also traverse the eyebrows, clefting them too!
So, eyebrows are the Swiss Army Knife of the human body—they do everything!
No comments:
Post a Comment