I had seen this gif online earlier and I thought it was pretty cool but kinda creepy. It's one of those photos that creeps me out but I can't stop looking at it. Who knew owls had 3 eyelids?! They have a top, bottom, and side eyelid. The side eyelid is called the nictitating membrane. The purpose of the side eyelid is to protect the eye and keep the surface clean. When the top eyelid closes that means the owl is blinking. When the bottom eyelid closes the owl is sleeping.
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