Ans:

The flounder is a fish with two eyes on one side, and it is a large group of saltwater fish, which includes flatfish, plaice, and sole. Flounder in the family of common "flounder", "spotted flounder", "flower flounder"; flounder in the family of common "high eye flounder", "rock sole"

Ichthyologists tell us that flounder are not born with this strange shape. The eyes of the newly hatched baby flounder are also born on both sides, and when it grows to about 3 centimeters long, the eyes start to "move", one side of the eyes to the top of the head, gradually moving across the top edge of the head to the other side, and then stop until it is close to the other eye. The habits of the flounder are very interesting, swimming in the water not like other fish with their backs up, but with the side of the eyes up, swimming sideways. It often lies flat on the bottom of the sea, covering its body with a layer of sand, exposing only its two eyes to wait for prey and avoid predation. In this way, the advantage of two eyes on one side is shown, of course, this is also the result of animal evolution and natural selection.

In the ancient times of China, the flounder is a strange fish that symbolizes faithful love, the ancients left a lot of good lines in praise of the flounder: "the phoenix amphibious fish than the eye", "to become a flounder why not resign to death, and would like to be a mandarin ducks do not envy the immortal," and so on, the famous dramatist of the Qing Dynasty, Li Yu, wrote a book describing the flounder, which is the most popular of the two. Li Yu has written a play describing the love story of a talented man and a beautiful woman, and its name is called "Bimu fish".

In fact, the ancient people's understanding of the flounder is wrong. Er Ya - the interpretation of the ground, said: "the East has than the eye of the焉, not than can not be, its name is called the flounder." "Wu Du Fu" also said: "Double is than the eye, the piece is the king Yu." (Note: "The flounder, produced in the East China Sea. Wang Yu fish, its body half also. Commonly known: Yue Wang chopped fish is not exhausted, and thus its half abandoned in the water for the fish, and then no side, so it is said that Wang Yu also.") The reason why the ancients called it "binomial fish" is because of its "shape of the spleen, scales fine, purple-black, one eye, two pieces together is to line, so it is called binomial fish." It has been said that the flounder is indeed a side of the eye, a side of the strange fish without eyes, but not only one eye, but two eyes close to one side, said it "two pieces together is to line" is very wrong, how can two fish together? Different classes of halibut eye position is not the same, turbot two eyes long in the left side, flounder and sole two eyes but long in the right side.