Camels have three eyelids. Two of the eyelids have eye lashes which help protect their eyes from sand. The third is a very thin lid which works as a sort of “windshield wiper” to clean off their eyes. It closes/opens from side to side rather than up and down. It is also thin enough that the Camels can see through it somewhat. So in a sandstorm or otherwise windy day where sand is being stirred up, they can close that lid to protect their eyes from the sand, but still see where they are going.

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