Our noses are more important than you probably imagined. A recent study found that women who smelled sweat that was produced during fear responded by making fearful facial expressions, and women who smelled sweat produced from disgust made disgusted facial expressions. Plus, the women’s behavior shifted based on what they’d smelled!

The women had no idea. The upshot? We don’t just communicate through our eyes and ears: Our noses play a big role, too. If you find yourself afraid in a big crowd, it might just be because you smelled everyone else’s fear, too.

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