This is what I call “the most foolish wise question” about fishes. Whenever you are asked, mere thinking at the surface, you think it is a simple question, but thinking deeper, you see you are in for something more difficult than you ever thought.
I have seen the question littering many question-and-answer forums, and having carried out enough research, I will give you the safest point to stand in this argument.
Are fish Wet or Dry? The answer depends on whether the fish is in or out of water. While swimming, you are not wet until you are out of water. Wetness can only be considered in a dry environment. On that basis, a fish in the water is not wet. But take a fish out of the water, you see water on its skin, so, it is not dry, it is wet.
A fish is not only in the water, but it also swallows some, so it is not dry. The same swallowed water is excreted through the gills to keep the fish dry and to manipulate gravity, so it is not wet.
There is a confusion that is sustained whenever this question is asked, and that is why considering many of the following will help you reach a safe answer.
What accounts for the dryness and wetness of a fish?
You cannot directly call a fish wet or dry. There are many things to be considered. First, it has to be what you mean by the word “wet”, and also, as said above, the place you find the fish has a lot to say in what your answer would be.
Anyone would ordinarily answer the question with a “yes” when asked, but when wetness and dryness is seen as a change in condition, then, it takes more thoughts to answer the question.
More: Can Fish Drown in Water?
A fish spends most of its lifetime in the water. Most edible fishes only leave the water once in their lifetime, and that is when they are about to be eaten.
If right from birth, a fish has been in the water, then, that is its natural condition. It is not wet, it is not dry, it is simply in water. Maybe there is something that situation is called, but it is definitely neither wet nor dry.
What if we consider how the gills function to keep the fish alive?
The natural environment of a fish in the water, and for it to stay alive, it needs oxygen, which because of its environment, it can only get from the water.
So, how does the fish breathes? It gulps water through the mouth, the water goes in until it gets to the feathery filament of the fish’s gills, then it goes back outside through the gills. It is in the gills that the oxygen extraction process takes place, and the extracted oxygen is sent into the bloodstream, where it is carried across every part of the fish.
This only means one thing: the surface of the gills must be wet to keep the fish alive.
The basic function of the gills is respiration. This means the gills collect oxygen and ensure it is distributed to the rest of the body. This can never occur if the gills are not wet.
So, if a fish in the water is said to be dry, and if “dry” means it contains no water, it means there is no way the gills are kept wet, which directly means there is no way the fish would be kept alive. A proof is that when you take your fish out of water and keep it there for long, it dies.
Some fishes would stay alive out of the water longer than other fishes and using the basis above, it could simply mean some fishes can hold water longer than the other. So, from this argument, a fish has to be wet. It is in water, and it absorbs quite a quantity of water.
But that is not the only function of the gill. It also works for excretion. Waste carbon dioxide in the bloodstream passes out through the gills into the water. Not only carbon dioxide but the water which the fish gulps, from which oxygen has been extracted at the feathery filament is passed out through the gills.
This only means one thing: the water gulped is not allowed to go into the fish’s body. Since a fish also manipulates gravity around itself by using its gills to push out water, so it will be dry.
That instantly paints a picture of a fish as half wet and half dry. Considering many factors, you will always find reasons to call the fish wet, and in the same place, call it dry.
What if we consider the skin of the fish?
The skin of a fish, just like the human skin, is hydrophobic. This means that it lacks affinity with water. Water can stay on it for long, but water cannot get it wet.
The best way to understand this is considering what happens to a paper or a piece of bread when it is dropped inside water. It physically changes, but the fish can stay in water for long and nothing will change.
This means that the fish does not absorb water through its skin, and if you bring it out of the water, what you will have on it is the water on the skin, which will only take some minutes before getting off. So, bring a paper or crumb of bread out of the water, you can call it wet because of what it looks like, but the skin of the fish will never absorb water.
What if we consider the environment?
The immediate environment of a fish in the water. The answer to this highly depends on what side of the argument we want to choose as humans, and what we mean by “wet” and “dry”. There has to be a point of contact between the two different environmental conditions before we can agree if it is wet or dry.
Take, for example, a person who wants to swim, before getting into the water, while changing into a swimsuit, is not said to be dry. Although the person is not wet, he is not dry. but immediately he gets into water, swims for a while and comes out, the person is said to be wet.
If he changes his clothes, cleans his body, and gets rid of the water on his skin, the person is said to be dry. This simply explains that wetness and dryness are only considered when there is a fast or sudden overlap of the two conditions.
Now, to the exact point of the example, we are interested in. While swimming, will a swimmer be said to be wet? Most unlikely. This is because there can only be a condition in the water, it is a condition that you can never be dry. It doesn’t directly mean you are wet, and what is the proof.
A person who was drenched by a light rain can be said to be “a little bit wet”, while a person who walked under a heavy rain would be said to be “so/very wet”. Can the same be said about a person who is underwater? No! He is not partially wet, he is not very wet, he is not wet, he is simply underwater.
On that basis, we can say that fish underwater is not wet. They are simply underwater. Yes, they are submerged, which paints a picture of wetness, but in the actual sense of how humans use language, they are not wet.
What about when they are taken out of water?
Then, there are two different conditions overlapping already. There is water on the skin, and there is air, so on that basis, the fish can be said to be wet. If it is wiped clean, then, it can be said to be dry.
What do fishes know about this?
The question of whether a fish is wet or dry is only left to humans to debate. It is nothing to the fish. This is because the water is their natural condition and they know nothing else.
Even humans, as smart as we are, are not conscious that we are dry until we get into the water, or take our bath. A person meets you on the road and asks “are you dry?”, the question would definitely sound stupid. But after swimming, bathing, or being under the rain, if you are asked the same question, you can answer yes or no.
This is because our natural environment is not wet. It is the same for fishes, that have almost no memory when compared to humans.
They never know they are wet, and when you take them out of the water, they start dying immediately, so they are asking themselves “what’s happening to me?” and not “am I dry or not?”.
Do fishes know when it’s raining?
No! Fishes don’t know it is raining, however, you can find them active when it is raining. This is simply because when raindrops on the water, they think it is food. They come up and find nothing, then, they go down, and come up again when they sense any other vibration.
Do fish know they are in water?
No! Water is all they have known from birth, so they never know there is another world, and when you take them out of the water, they fight for survival rather than study the environment. If you put them back, they have low memory ability, so they forget all.