Welcome to brain Stuff from house stuffworks dot com where smart happens. Hi Am Marshall Brain with today's question, why do human beings have eyebrows? 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 when we walk around in the rain. The art 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 when we're out in the rain. Without eyebrows, getting around in these conditions is a little more difficult. Diverting this sweat away is also good because the salt and sweat irritates the eyes, making them sting a little. Eyebrows are a very significant aspect of our pearance. 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 is 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 for our faces. There's beauty, nonverbal communication, distinctive appearance, the whole water shedding thing. But most scientists are inclined to believe that if we didn't have eyebrows, something else would have evolved to help
the situation. For example, humans could have developed incredibly thick eyelashes to shield out excess sweater rained or our skulls could have continued to protrude so that they formed a ledge above our eyes. Rain or sweat would then drop from that ledge, straight away from our faces without going into our eyes. For more on this and thousands of other topics, visit how stuff works dot com and don't forget to check out the brain stuff blog on the
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