How do fish not blink?

Fish don't blink in the same way that humans do because they don't have eyelids!

Here's why:

* Different environment: Fish live underwater, where their eyes are constantly bathed in water. This provides a protective barrier and keeps their eyes moist.

* Protective membranes: Fish have a thin, transparent membrane called the nictitating membrane that covers their eyes. This membrane can move across the eye to provide extra protection from debris or predators.

* Constant eye lubrication: Fish have a constant flow of water over their eyes, which helps keep them clean and lubricated. This means they don't need the blinking reflex to moisten their eyes.

So, while fish might not blink in the same way as humans, they do have their own unique ways of protecting and caring for their eyes.