You know that deer-in-the-headlights look? Well, it might serve an evolutionary purpose. Researchers at Cornell University have determined that in the face of danger, our eyes widen, mirroring our pupils, to let in the maximum amount of light and open our field of view in order to see as much as possible—and therefore stay as safe as possible. This is very different from the face we make when we feel disgusted. Then, we squint, an action that focuses light to let us pinpoint just what’s causing us to say “Ew.”

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