The camel has a third eyelid.
The third eyelid on a frog is called a nictitating membrane.
Camel
Yes, pigs do have a third eyelid, also known as a nictitating membrane. This protective eyelid helps to keep the eye moist and shield it from debris while still allowing for some visibility. The third eyelid is a common feature in many animals, including pigs, and plays a role in eye health.
A cat's third eyelid becomes more visible when they are sleepy because their eye muscles relax, allowing the third eyelid to move across the eye and become more noticeable.
A nictitating membrane The nictitating membrane is the THIRD eyelid, the SECOND eyelid that you asked about is just that, the eyelid, just like in humans
The Sahara covers about one third of the African continent.
Nictitating Membrane
The Sahara covers the northern third of Africa.
The Sahara covers most of the northern third of Africa.
Cats sometimes have their third eyelid showing when they are sleeping because it helps protect their eyes and keep them moist while they are resting.
Yes because it is to help the frogs see under water
In the Sahara desert you would only find animals at an oasis.