Weird blind fish

Several rare blind fish have been discovered in dark underground caves in southwest China. The largest body length of these blind fish is less than 10 centimeters, and their appearance is very strange: the slender body is pink and transparent, and the spine and internal organs in its body can be clearly seen, shaped like glass fish. They have acquired new abilities in their long-term struggle against darkness. They can endure hunger, are not afraid of cold, and are not afraid of heat. It will not die when the water temperature is -10~35℃, and its vitality is extremely strong. There are also traces of blind fish in underwater caves in Yunnan, Guangxi, Sichuan and other places in my country.

There are many places in the world where various types of fish also live in completely dark caves. For example, the North American cave bass and the Cuban blind bass are both famous blind fish.

Cave bass are very small, generally only growing to 16-20 centimeters. There are black vertical stripes on the body, and the eyes have been covered by the skin, leaving only a trace. So how does this blind fish behave? There are many small protrusions of different shapes on its head and body. These small protrusions can play a sensory role and can completely replace the eyes, so that even if they are in a dark environment all year round, they can still swim around freely.

The blind bearded bastard is very beautiful. Its whole body is pink, and some are bronze. It is also covered with small black spots. Its body length is generally 15 centimeters. This kind of fish has relatively developed eyes when it is young. When it reaches adulthood, the eyes are gradually covered by skin and become blind. At the same time, many small sensitive whiskers grow on the head to replace the eyes.

A blind goby fish that is only 10 centimeters long can be found in rock crevices or caves under rocks along the coast of southern California. The skin of this fish is light red, smooth and scaleless. When it is young, its eyes are small but can see. Once it grows up, its eyes are hidden under the skin. Although it is blind, it can swim around in the dark cave and be extremely active. This is because there are many skin receptors on its head, and it can quickly explore food by relying on these receptors.

There is also a kind of Mexican fish, which has a pair of very cute big round eyes when it is young. Observations and experiments by ichthyologists have found that its eyes naturally gradually degenerate during the development and growth process, and its activities rely entirely on its skin to sense light and external stimulation.

There is also a more peculiar kind of blind fish called the hagfish, which was formed after the appearance of real fish. It mainly lives in the waters of Kamchatka Peninsula and is the only fish in the world that breathes through its nose. Although the eyes of the hagfish are also covered by a layer of skin, this fish not only has receptors on its head, but its whole body is also covered with supersensory cells, which can determine the direction and distinguish objects relatively accurately. It can also penetrate into the body of large fish, swallow the fish's internal organs, and then drill out of the fish body with its receptors. Sometimes it also penetrates into the fishing net to prey on the fish in the net, and when the fishermen raise the net, it And can quickly escape from the net. This kind of fish has a very strong hunger tolerance and will not starve to death even if it does not eat for half a year. The hagfish has four hearts. Why it has so many hearts is still a mystery. Hagfish can also secrete a special kind of mucus that can stick the surrounding seawater into a ball. When enemies are confused by this mucus, the hagfish has already fled away. Hagfish generally feed on tiny crustaceans or plankton.

animal tags： fish hagfish