If i am not wrong, and iirc, they have different lens systems as compared to humans (or other land dwelling beings). For us, light goes from air to a lens made of “watery” substance and then through a (different) “watery” fluid in our eyes, and then to the back. whenever you have refractive index changes (air and water have different indices(water is ~1.33)), light bends, and so, the way light would refract differently, or in other words, the angle at which “focuses” (not the current optical term here, but works in a colloquial sense, angle of cone of focus would be better) is different if you have air-watery*-watery system vs water-watery*-watery system. since fish live in water mostly, they develop for the lattery system (since most of the system is water esque, there is not much refractive difference which would bend light at larger angles), so they would have to use a more “powerful” (not correct again, better would be shorter focus) lenses, or else there eyes and eye sockets would have to be large. so if they come above water, these “powerful” lenses would resolve the focus spot before the back of eye (so they would be myopic). inverse happens with land dwelling beings going in water.
Amphibians (and some other “beings”) have some special “arrangements”. iirc, some frogs have an extra layer of “transparent eyelid” like thingy, that they close underwater, which gives the “additiional focussing power” required to resolve.
psx_crab@lemmy.zip 1 month ago
What i mean is they can’t see well while out of water, just like we can’t see well when we’re underwater. Our eye evolved to see above water, so when we try to see underwater, the water will mess up the light going into our eye, so everything would be blurry for us. The reverse is true for fish as well. So while they poke their head out as if they trying to take a peek, what they most likely see is blurry mess.
chloroken@lemmy.ml 5 weeks ago
This is the dumbest thing I’ve ever read. Holy.
What do you think makes vision blurry under water?
shalafi@lemmy.world 5 weeks ago
What makes you think fish and human eyes didn’t evolve for their environment?
Strawberry@lemmy.blahaj.zone 5 weeks ago
Lol, considering how they are right, I am wondering what you think makes vision blurry underwater
chloroken@lemmy.ml 5 weeks ago
We see a blurry mess underwater because of the particulates in the water. Fish don’t see a blurry mess when they look through air.
People being clueless is not my worry.