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Biology

What's the science behind closing our eyes when we sneeze?

Quick fact

Sneezing is a protective reflex that expels irritants from the nasal passages, triggered by nerve endings in the nose responding to dust, allergens, or pathogens.

Why this is interesting

A sneeze rockets out of your nose at speeds up to 100 mph, but your eyes close automatically not to protect them—it's a vestigial reflex from when our ancestors sneezed while chewing leaves, but no one knows why.