Why do we have eyebrows?
[ 2006-07-21 11:11 ]
有人說眼睛是心靈的窗戶，那么眼眉就是窗戶的保護(hù)傘了。這把保護(hù)傘除了把人裝扮得更加靚麗外，還有非常大的實(shí)用價(jià)值。是什么呢？請(qǐng)看下文。
 Eyebrows are a very significant aspect of our appearance. They
are one of the most distinctive features that make up our faces, and we pay a
lot of attention to them. We think of some types of eyebrows as attractive and
some as unattractive, and many people spend as much time preening their eyebrows
as they do applying makeup to their eyelashes or lips. Eyebrows are also one of
our most expressive facial features. One of the clearest ways to tell somebody
what you're thinking is to simply move your eyebrows up or down -- we all know
what different eyebrow positions mean.
So, eyebrows obviously serve a
lot of functions in our culture today -- beauty, nonverbal communication,
distinctive appearance. But why are they there in the first place? As we evolved
and lost most of the thick hair on our bodies, why did we keep that little bit
over the eyes?
Scientists aren't entirely sure why we kept this hair,
but they have a pretty good guess. We know that eyebrows help keep moisture out
of our eyes when we sweat or walk around in the rain. The arch shape diverts the
rain or sweat around to the sides of our face, keeping our eyes relatively dry.
The most obvious advantage of this is that it lets us see clearly when we're
sweating a lot or out in the rain. Without eyebrows, getting around in these
conditions is a little more difficult. The shape of your brow itself diverts a
certain amount of moisture, but eyebrows make a significant difference in your
ability to see. Diverting the sweat away is also good because the salt in sweat
irritates the eyes, making them sting a little.
There are a number of
ways these qualities might have helped early man survive. Being able to see more
clearly in the rain could certainly help you find shelter, and there are several
circumstances when keeping the sweat out of your eyes could save your life. If
you were trying to outrun a predator, for example, it's a good bet there would
be a lot sweat running down your face. If all that sweat flowed right down into
your eyes, you wouldn't be able to see that well, and your eyes would be
irritated, which would certainly impair your ability to escape! Because of this
slight survival advantage, nature would most likely select humans with eyebrows
over humans without eyebrows.
predator：肉食動(dòng)物
（英語(yǔ)點(diǎn)津 Annabel 編輯）
|
