Animal anecdotes

China Student Encyclopedia: Animal Anecdotes

A fish whose edge is hard to find.

We all know the idiom "seeking fish from the edge of a tree", which means that people climb up a tree to catch fish, but in vain, laughing at those who don't grasp the main point. However, in the southern coast of China, there is a kind of fish whose hard edges are hard to find, which is an amphibious tree-climbing tántú fish, also called "jumping fish" or "jumping fish". In addition to the southern coast of China, this fish also lives in the tropical coast of West Africa and the Pacific Ocean. They often jump from sea water to flat beaches or wet lowlands.

Why do mudskippers have this ability? Because the base of the pectoral fin of the mudskipper is long and thick, which is a bit like the forelimbs of land animals. Its pectoral fins are not only swimmers, but also supporters. It jumps and crawls on the beach with the support of the pectoral fin of its arm, the bouncing ability of its body and the push of its tail, and sometimes it can climb to the branches of the sea.

What's more, although this fish can't live without water for a long time, it is used to living on land and has to climb to land from time to time. In addition, they also have the ability to prey on land insects and crustaceans.

Since the mudskipper is a fish, how does it breathe after leaving the water? As we know, fish generally breathe air through gills in water, while mudskippers mainly rely on skin to help them breathe besides gills, so they can survive without water.

From this fish, we can clearly see that the process of life evolution is indeed from aquatic to terrestrial. This provides strong evidence for the evolution of life.

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Fish that can generate electricity

The first Spaniards who arrived in America invented a story: in the jungle of South America, there is an extremely rich area where the trees are covered with pure gold. In order to find this treasure house of nature, an expedition led by Spanish Dixika went upstream along the Amazon River and came to the edge of a large swamp. In the dry season, the swamp is almost dry, and only a few small ponds in the distance twinkle in the midday sun.

The expedition came to the small pond. At this time, the Indians hired by the expedition were shocked and afraid and refused to walk through the shallow pool. Dixieka ordered a Spanish soldier to show it to the Indians. So the soldier walked into the water with indifference. However, just a few steps away, he let out a cry and fell to the ground, as if he had been hit hard by someone. His two companions rushed forward to save him, and were knocked down by the invisible enemy and lying in the mud. A few hours later, in the absence of any movement in the water, the soldiers carefully walked into the water and rescued three wounded people. However, at this time, all three of them were paralyzed.

Later, people learned that this unknown monster is the freshwater electric eel.

South American electric eel is a large fish, which looks like a snake, more than 2 meters long and weighs more than 20 kilograms. Usually, electric eels lie motionless at the bottom of the water, and sometimes they surface. Electric eels can generate electricity, electrocute shrimps, fish and frogs, and then have a full meal. When it is attacked, it will immediately send out electricity to repel the enemy's attack in one fell swoop. Electric eels not only use electric discharge to find food and deal with enemies, but also are used for underwater communication and navigation. It has been found that when the male electric eel approaches the female electric eel, the intensity of the current will change, which is what they say hello to!

In fact, the ability to discharge is not unique to electric eels. Now people find that there are more than 500 kinds of fish that can discharge in the oceans and fresh water all over the world, such as electric sturgeon, electric ray, electric catfish and so on. People collectively refer to these fish as "electric fish". There is an African electric catfish that can generate 350 volts, which can kill small fish and make people and animals unconscious; South American electric eel can be called "electric shock champion", which can generate up to 880 volts; North Atlantic giant thunder can light 30 100 watt bulbs in one discharge.

Why can the electric fish send out such a big current? After careful anatomical research and experiments, scientists finally found a strange electric officer in the electric fish. All kinds of electric fish have different positions and shapes. The electric appliances of electric eel are distributed in the muscles on both sides of the caudal spine, which are long prisms; Torpedo's electrical appliances are like two flat kidneys, arranged on both sides of the body, and have a honeycomb structure composed of hexagonal cylinders, which is called an electric disk. Among the two electrical officers of the torpedo, * * * has 2 million electric plates. The electric catfish has more plates, about 5 million pieces. Under the control of the nervous system, the electrical officer released electricity. The voltage generated by a single plate is very weak, but because there are many plates, the voltage generated is considerable.

Interestingly, the earliest and simplest battery in the world, the Volta battery, was designed by Italian physicists at the beginning of 19 century according to the electric officers of torpedoes and electric eels. At first, Volta inserted copper sheets and zinc sheets into salt water to make a DC battery, but the current generated by this battery was very weak. Later, he imitated the electric officer of the electric fish and alternately stacked many copper sheets, paper sheets soaked in salt water and zinc sheets, thus obtaining a relatively high-power DC battery.

Studying electric fish can also bring many benefits to people. For example, once we can successfully imitate the electric officer of electric fish to generate electricity in seawater, the power problem of ships and submarines can be well solved.

Some scientists intend to imitate the power generation mechanism of electric fish and create new communication instruments. In this regard, electric eels and elephant trunk fish can provide valuable enlightenment. Elephant trunk fish is an electric fish, which lives in rivers and lakes in central Africa. Its nose is very long, a bit like an elephant's nose, so people call it elephant-nosed fish. The fish's electrical appliances are at the tail, and there is something on its back that can receive radio waves, just like a radar antenna. When the enemy approaches a certain distance, the reflected electromagnetic wave will be received by the radio receiver on the back, and the enemy will be alerted when it is found. At this time, the elephant trunk fish hurried away.

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Fish that can "fish"

Humans can fish. As we all know, if fish can "fish", you must be surprised. This strange fish that can fish lives in the deep sea and is called "hornfish".

How does it catch fish? It turns out that this fish has a bait whisker on its head, just like the fishing rod in our hands, and the top of the whisker is the favorite bait of other fish. This bait is luminous. Luminous bait is actually a kind of luminous gland, which can secrete granular things, and there are many luminous bacteria in it. It secretes a liquid to feed bacteria, which can catch small fish by emitting light. Hornfish and luminescent bacteria live a life of * * * *, but this kind of luminous gland is only found in female hornfish, and there is no luminous gland at the top of male lure.

Some hornfish must be short and thick, while others are thin and long. Different hornfish will emit different colors, such as purple-orange, yellow, blue-green and so on. Because the deep sea is dark, when they shine continuously, they will attract the attention and interest of the surrounding fish and crustaceans, rush to the flash, "voluntarily" catch the fish and fall into the belly of the fish.

The appearance of hornfish also provides convenience for its "fishing". Its back is brown, and there are many small protruding things, which are very similar to its surrounding environment, so it is difficult for other animals to find it. It has a very wide mouth. The width of the mouth is 1/4 of its body length, and there are sharp teeth in it.

This kind of fish is not very good at swimming. It always glides slowly in the dark ocean. Along the way, it stretched out the bait from time to time, and the flashing bait was pulled by the muscles and trembled from time to time. Use its linear organs to detect the movement of the surrounding grapples. Because of this action of the hornfish, a fish who meets the light often thinks that he has found a favorite bait, so he tries to test this luminous bait with his mouth. This contact alarmed the hornfish, which immediately sent out a series of predation actions. Suddenly, it raised its lure whiskers backward, opened its jaws, and formed a stream of water flowing into its mouth, easily swallowing its prey into its wide mouth.

This is the way for rhinoceros fish to "get something for nothing". It doesn't need to move by itself, and the small fish will be automatically sent to its mouth and become its food to satisfy its hunger, which is much better than our human fishing.

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Fish that live in hot water.

According to common sense, fish can only live in cold water. If you put a fish in water above 50℃, it can still swim freely. You must think it's strange. However, nature often gives us some surprises.

1936 In the summer, a French traveler named Rip unfortunately ran aground at sea and was swept by the waves to a mountainous volcanic island in the Thousand Islands. At that time, he was hungry and looking for something to eat. Suddenly, he found some dead fish lying in the river, so he fished them up and took out the only cooker left around him to cook fish soup. After burning for a while, Rip couldn't wait to lift the lid. Unexpectedly, this startled him. The original dead fish turned into live fish and swam leisurely. What's going on here? The traveler is simply inexplicable!

Later, after people's investigation and study, it was known that the island was originally a huge ancient crater. These strange fish are "residents" in a small lake heated by volcanic rocks. At that time, their ancestors were survivors of this volcanic eruption. According to the measurement, the water temperature in this lake is as high as 63℃, and ordinary fish can't survive in this environment. This kind of tropical fish can live well. Even more surprising: because they have adapted to hot water, once they fall into cold water, they will freeze to death immediately.

In the natural environment, hot water fish is very rare. In addition to the places mentioned above, you can occasionally see them in hot springs near Lake Baikal and a river in California, where the water temperature is generally 45℃ ~ 55℃. It seems that the temperature range that organisms can adapt to is much larger than we thought.

Ordinary creatures can also accept exercise and expand their adaptation to life. The change of an environment is a test of biological toughness, and the continuation of species always goes through several generations of adaptation and evolution. However, scientists have little research on the mechanism of improving the high temperature tolerance of organisms. If some students are interested, they can learn more about this from now on, which may fill a gap in the future.

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Hatch Vietnamese fish with your mouth.

Reproduction is the ability of natural creatures and an important guarantee for the continuation of life. Fierce carnivores like lions and tigers are "kind" to their cubs, nursing and feeding them and teaching them how to hunt. Another example is the birds and raptors in the sky. They also take good care of their eggs to ensure that their chicks hatch and grow up safely. Although animals reproduce in different ways, they love their offspring the same.

The reproductive habits of Vietnamese fish are quite strange among fish.

During the breeding season, Vietnamese fish will lean against the bottom of the pool, then lean sideways and gradually dig a pot-shaped nest. The female lays eggs in the nest, and the male ejaculates on the eggs. After the egg is fertilized, the female fish hatches the egg in her mouth. When the water temperature is 25℃ ~ 27℃, the small fish can hatch in about 4 ~ 5 days. After hatching, the small fish still live in the female's mouth for about a week. During this time, the small fish will run to the mouth of the female fish to avoid any danger and will not be eaten by the female fish; But after this time, the responsibility of protecting the female fish is over, and the small fish are released from the export. From then on, the "loving" mother god met small fish, including her own, which would be swallowed.

An instinct of Vietnamese fish is to hatch and protect the newly hatched young fish with eggs in their mouths. This instinct enables Vietnamese fish that only lay dozens to hundreds of eggs at a time to survive well.

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Fish that can fire water guns

In India and Southeast Asia, there is a kind of water-shooting fish called "live water gun" and "sharpshooter", also known as water-bomb fish. He is fifteen or sixteen centimeters long, silvery white and flat, and his appearance is not strange. Its special function is to spray water on its prey. When it swims, its eyes always stare at the water to see if there is anything delicious. When it finds flies, mosquitoes, dragonflies and other insects flying over the water surface, or stopping on the grass or rocks near the water surface, it will gently swim to the place about 1 m away from the insects, unfold the shelf, stick its head out of the water surface, clench its beak, straighten up, aim the prepared water at the target with its mouth, and spray a "water bomb" with great power to hit and drop its prey like archery. People in Australia and other places like to feed this interesting fish. Be careful when you look. It will shoot at random. If you feed, it will also target your hand and shoot with water; If you look down at the fish tank, it is even more dangerous, because as long as your eyes blink, it will attract its attention. Shoot you rudely while you're unprepared, and hit you in the eye with water bullets. Don't smoke near the fish tank when guests come to visit. The flashing lights will attract him to swim over and shoot cigarettes. It can really kill cigarette butts like missiles.

Why can swordfish explode "water bombs" and hit so high? This is not only related to the special structure of its mouth, it can quickly form a string of water droplets from a large number of stored water, but also related to its special eye vision. Shooting fish's eyes are big and prominent, they can rotate flexibly, and their retinas are particularly developed. Generally, fish can't see clearly in the air because there is no water as a lubricant for the eyeball. Shooting fish can see both things in the water and things outside the water. Scientists used high-speed cameras to take photos of water bombs fired by water-shooting fish. It was found that after sunlight refracted into the water, water-shooting fish could make complex corrections to the position changes caused by light refraction when aiming at the target. Moreover, changing the body into a vertical posture and throwing the launched "water bomb" in a straight line can overcome the deviation of light refraction and ensure accurate shooting. What an excellent shooter!

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Fish that can jump high and fish that can fly.

Generally, fish can jump out of the water, such as "carp yue longmen" which is often said in China. But they don't jump too high out of the water. They all jump out of the water with the help of the muscle strength of the fish, mainly the strong twisting and jumping movement of the tail muscles, rather than the action of fins. The real champion of "high jump" is loach fish, which can jump 6 meters above the water, which is higher than the general record of pole vault!

At present, there are only two species of loach found in the world, which are widely distributed according to their size and are often seen in the South China Sea. They often move in the upper waters, so that they can jump out of the water to hunt at any time. The high jump of this fish relies on huge and powerful fins, slapping the water and then jumping up. Their ability to jump high is exercised in the process of preying on flying fish for a long time, because they love flying fish.

When it comes to flying fish, its ability is not small. Its chest has two deployable fins, just like the two wings of a bird. When it was chased by a loach fish, it rushed out of the water at a very fast speed, and the long and powerful tail handle and the lower leaf of the tail fin slammed into the water, making the fish soar, and immediately spread its wide "wings"-pectoral fin, gliding on the sea surface, generally gliding 18 meters per second, with a height of 8 ~ 10 meters and a maximum distance of over 300 meters. Therefore, it is not easy for loach fish to catch flying fish, so they developed the specialty of high jump in the competition for survival-you can fly, I can jump, and sometimes the jump is even higher than flying fish. Therefore, we can often see interesting scenes. When the flying fish glided leisurely on the sea, suddenly the loach jumped up and bit the flying fish in the air. The flying fish became a delicious meal. It's really one foot high, ten feet high, everything has its vanquisher!

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Fish that can build a house

The famous "architect" in fish is the three-spined spiny fish. Whenever they want to get married and start a family, they should design, build and build a strong and beautiful "new house" in advance. The foundation of a house is generally selected between aquatic plants or pools and depressions in rocky areas, requiring appropriate water depth and frequent water flow. After the foundation is selected, prepare materials and collect some plant fragments such as water grass roots. The male fish secretes a mucus from the kidney, sticks these substances together, and then bites them with his mouth until he bites out the shape of the nest. In order to strengthen the house, it smeared, rubbed and decorated the inside and outside of the house, making the surface neat and smooth, as if it were painted with a layer of varnish. The completed house is hollow in the middle, slightly oval, with two holes, an exit and an entrance. It was a success, so the male fish swam around and admired his masterpiece. The future groom began to look for the future "bride". Once he takes a fancy to it, he will make a set of complicated courtship moves to lure the female fish into his carefully built house and ask the "bride" for advice. If the female fish is satisfied, they both enter the "bridal chamber". If the "bride" is shy and pretends to refuse to enter the room, then the "groom" will erect a thorn on his back and force the "bride" to enter. After the female fish enters the nest, she lays two or three eggs and then walks through the hall. The male fish immediately injects semen into the egg. The next day, the male fish pulls another female fish to lay eggs and mate until the house is full of eggs. This beautiful "new house" has become a very safe and comfortable nursery.

Another person who can build a house is an octopus. They live on the bottom of the sea and have many long tentacles. When octopus is full, they always have a good sleep in a quiet place. In order not to be disturbed, it dragged its bloated belly and built a sleeping nest. It carries stones with its tentacles, and it can carry four or five kilograms of stones at a time. After the fence was built, it found a flat stone as the roof, and the small house was built. It lazily got into bed. In order to guard against the enemy's harm, it makes two tentacles specializing in defense duties stick out of the room and keep swinging, as if they were "standing guard". Once an enemy invades, the octopus will wake up, fight or abandon the house and run away.

There is also a fish that can build a house like a bamboo tube called a hole-drilling fish. They live in the deep seabed of the Atlantic Ocean, about 1 m long, with yellow spots and blue tails, and beautiful colors. Its specialty is digging holes. As long as it is caught by big fish or fishermen, it can quickly and sensitively drill into the holes. Its hole is its own nest, and it is carried around like a snail, but it is shaped like a bamboo tube. It can find plant fragments, pebbles, etc. Then stick them into a cylinder with mucus secreted by the mouth and surround them around the body. The hole is small and easy to hide, and it usually moves with the house when walking.

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Fish capable of fencing and stabbing

In tropical waters such as the Indian Ocean, there is a fierce big fish, about 3 meters long, with a long, flat and hard "sword" protruding from the upper jaw, which is called "swordfish". It swims very fast and rampages in the sea. Even sharks are afraid of it. When swordfish attack whales, they often stab them in the heart with their long mouths like swords. It treats small fish with its sword mouth, chopping left and right, and then eating the stabbed or chopped ones. Once, a British ship Trinato was punctured at the bottom by a swordfish while sailing from London to Ceylon (now Sri Lanka), causing the ship to leak. Because of its difficult rescue, it avoided sinking. You know, the hull of this ship is covered with thick iron sheets, and swordfish can actually pierce it, which shows the fierce attack of this fish.

Siniperca chuatsi is a delicious freshwater fish with black patches on its silver-gray body, about 60 cm long, and a dorsal fin as sharp as a knife on its back. It is also good at preying on other fish with a "back knife" to satisfy its hunger.

The most ingenious thing is that it can trap water snakes and has a unique skill. For a long time from late spring to autumn, mandarin fish always live near big rocks, swimming around, often pretending to be dead and floating sideways on the water. When the snake found that such a delicious fish was sent to the door, it immediately swam close to the fish and entangled it. When the snake wound around the mandarin fish more and more tightly, suddenly the mandarin fish used all its strength to open the dorsal fin like a knife on its back and twist its body quickly. Soon, the executioner saw a series of deep wounds in the snake's abdomen and other places. The snake dived into the water in pain, and the mandarin fish chased after it, killing the seriously injured snake and then having a good meal.

There is also a kind of fish with thorns all over its body, which looks like thorns on land and is called blunt thorns. The whole body is oval, and the body length is only 10 cm. There are thick thorns all over the body, and each thorn has two or three, all of which are evolved from scales. Its mouth is small, its upper and lower teeth are connected together, and its tail fin is like a fan. When it was threatened, it quickly rose to the surface of the sea to absorb enough air, expanded into a round thorn ball, and each thorn stood up and rolled over to stab the big fish that threatened it. This skill is really fierce, scaring away all the big fish. Blunt fish also prey on small fish in this way.