cats can sleep with there eyes opened my friend has a cat and her baby cat always sleep like that
Fish and Snakes, as most of them do not have eyelids.
Get a certain sickness called Urnobobquia. Unfortunately, this can kill you.
They often do but will also close them on occasion.
The purpose of the eyelid is to keep the eye moist. Fish live in water, and so the eye does't need moistening, and so fish don't have eyelids. Thus they sleep with their eyes open because they have...
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