Most likely for protection for their eyes, some tend to be delicate.
Most snakes have no eyelids or legs.
Dogs actually have 3 eyelids.
Fishes have no eyelids as the water in which they live bathes them.insects
No,neither do fish
three
Three
they have three eyelids i read in a real book about ducks
Three
camel
One clear one to see under water and another to completely close their eyes. They have one pair of eyes, with two pairs of eyelids: one regular pair, and an inner eyelid that is transparent called a nictitating membrane, used to protect their eyes when underwater. Sometimes it will be said that they have three eyelids, because you can count the regular eyelids as two, top and bottom, and the nictitating membrane as number three.
Three. They have the upper and lower lids, similar to humans. They also have a third membrane that acts as an eyelid, so to speak. The third "eyelid" moves from the outside edge to the inside edge.
It is said mallards have three eyelids per eye. I have never directly observed that. I have only seen one that closes from the bottom instead of from the top.