What fish can blink both eyes?

That's a fun question! While fish have eyelids, they don't blink in the same way humans do.

No fish can blink both eyes independently.

Here's why:

* Eyelid Structure: Fish eyelids are mostly transparent membranes called "nictitating membranes" which slide across the eye from the inside. They don't close completely like human eyelids.

* Function: The nictitating membrane's primary purpose is to protect the eye from debris and help with underwater visibility. It can be drawn over the eye when needed, similar to a windshield wiper.

So, while fish have eyelids, they don't blink in the traditional sense.