5 underwater creatures with extraordinary vision

Can Fish See Water?
It might sound like a strange question at first—can fish see water? But when you think about how we don’t really “see” the air around us, it starts to make sense. Just like we walk around all day surrounded by air we don’t notice, fish are constantly swimming through water without really “seeing” it.
The Short Answer: No, fish don’t see water—at least not in the way we might think.
Their brains, like ours, are wired to filter out constant, unchanging things in their environment. It’s kind of like how we don’t notice our own nose in our field of vision unless we focus on it. Our brains decide that air isn’t worth paying attention to—and fish brains do the same with water.
Why Don’t Fish See Water?
It all comes down to survival and efficiency. A fish’s brain is busy focusing on things that matter—like predators, prey, and obstacles—not the water itself. Over time, their brains have learned to tune out the water since it's always there and doesn’t change much. This is what scientists call “environmental noise.”
Think of it like background music in a store. It’s there, but you don’t really notice it unless it suddenly changes or stops. Water is the background for fish. Their brains just don’t bother highlighting it.
Can Fish See Air?
Nope, and neither can we. Air has such a low refractive index that it’s essentially invisible to the eye—human or fish. So even when a fish pops its head out of the water, it still doesn’t “see” air the way we might imagine.
How Well Do Fish See Underwater?
Now this is where it gets interesting. While we tend to get blurry vision underwater (unless we’re wearing goggles), fish have eyes that are made for the job. Their eyes are rounder than ours, which helps bend light more effectively underwater. That gives them a clearer picture of their world than we could ever get just swimming around with open eyes.
When we dive in, our flat eyes and the density of water don’t mix well—hence the goggles. But fish? Their vision is sharp and adapted to the watery world around them.
Underwater Creatures with Super Vision
Some sea creatures take underwater vision to the next level. Here are a few favorites:
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Octopus: Their eyes are incredibly complex, even more so than ours. They’ve got more nerve endings and can detect light in ways we’re just beginning to understand.
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Barreleye Fish: These deep-sea dwellers live at extreme depths and have developed some of the most specialized eyes out there—perfect for seeing in near darkness.
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Mantis Shrimp: These guys are the rockstars of vision. They’ve got 12 color receptors (we only have 3), and each eye moves independently. Their color perception is out of this world.
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Cuatro Ojos (Four-Eyed Fish): Okay, they don’t actually have four eyes. But each eye is split in half so they can see above and below the water at the same time. Pretty clever!
So, Do Fish See Water?
Not really. Just like we don’t see air, fish don’t notice water in their day-to-day life. Their brains are built to focus on what matters for survival, not the stuff that’s always there. But when it comes to seeing what’s around them in the water? Fish are seriously impressive.