Do fish know pain? Do fish feel pain?

It hurts, plants have nervous systems, not to mention animals. There are some types of fish that can't be put together, so hurry up and separate the fish that can't be put together. Don't kill him, although he is blind, he still has the right to live.

Definitely. Because it has a nervous system. But your fish is so pathetic, you don't have to kill it. The position of the eye must have been restored. It's just that the eyes are gone. It definitely doesn't feel it now. Let it live well.

It hurts. Quarantine him, poor one.

Take care of it.

He was blind, but he was still alive.

What a brave fish!!

I'm going to put it in my composition.

It will definitely hurt too, and don't put different species of fish in the same tank, they will attack each other, it's pathetic.

Of course I do.

But it doesn't just cry.

There are wounded people in the tank, pay attention to the maintenance of water quality, although it is difficult, it is still trying to live, to protect it, do not let its wound infection.

Cold, you see if it moves, it's very painful, the fish will move when it's out of the water, whether it hurts or not can only be observed.

Hurry up and separate those strips, and don't let the tragedy happen again.

Don't kill it, my grandmother's family used to raise goldfish for several years, and I changed the water and touched my eyes, but the goldfish is still alive and well, just get used to it, don't touch it.

Of course, I know that individual creatures know pain, including flowers and trees.

Do you know the pain? You know if fish know pain.

Yes Otherwise, they wouldn't struggle.

The fish does not hurt when you kill the fish. A recent study concluded that fish lack the necessary pain receptors in their brains and are therefore unable to experience pain in the same way that humans and other animals do. Although fish possess nociceptors, these sensory receptors are able to respond to objects or events that harm their bodies by sending warning signals to their brains.

According to the authors of the study, the function of these receptors in fish is not the same as in humans.

"Even if fish were conscious, there is no evidence that they have the same pain sensations as humans," the study's authors wrote in a study synopsis. The researchers claim that a nociceptor called a C-fiber nociceptor in humans is the main cause of pain in humans, but this receptor is rare in finfish and is found in sharks and rays.

It doesn't exist in the body. The researchers wrote that another A-triangle nociceptor triggers another simple reflex escape that is fundamentally different from real pain.

Suffering.

When the fish breathes in the water, the gills are all open, which can increase the contact area with the water and help absorb more oxygen, but once out of the water, the adhesions of the gills cannot be opened normally due to the lack of water in the gills by the sail, which is not conducive to the fish's breathing. Therefore, slowly the fish will die of lack of oxygen.

Fish can be roughly divided into two categories, one is freshwater fish, the other is saltwater fish, but no matter what kind of fish has no water supply, the balance in their body will be broken, and eventually the oxygen in the body will be reduced, carbon dioxide will increase, and finally suffocation. However, not all fish are inseparable from water, there is a lungfish that has a gills similar to a lung structure, which can be used to breathe and feed after leaving the person, so as to maintain the vitality of the fish.

The evolution of fish

The first fish were jawless, as the name suggests, that is, fish without upper and lower jaw nuclei, they could not hunt by opening and closing their mouths, and sucked water containing microscopic animals and sediments into their mouths, and one of them was also covered with hard bone fragments "armor" and lived on the bottom of the sea. They first appeared in the Early Cambrian more than 500 million years ago, and were the first fish to differentiate, and the main representative of jawless in the ocean at that time was the armored fish.

Later, due to genetic mutations, there was the first fish with jaws, jawed fish can actively and effectively prey, under the natural selection of "natural selection, survival of the fittest", more and more jawed fish began to appear, jawless fish fell into the disadvantage in the hunting competition, the emergence of jawed fish, so that the survival competition in the ocean became more and more intense, "big fish eat small fish, small fish eat shrimp" food chain, has been formed since then.