Why do humans have a third eyelid? - Dorsa Amir

Discover how evolution and natural selection influence why the human body has vestigial organs— body parts that no longer serve their original purpose. -- You know that little pink thing nestled in the corner of your eye? It’s actually the remnant of a third eyelid. In humans, it’s vestigial, meaning it no longer serves its original purpose. There are several other vestigial structures in the human body, quietly riding along from one of our ancestor species to the next. But why have they stuck around for