Underwater world animal and plant information

The blue whale is the largest known animal in the world, with a blue-gray body. At present, the time for catching the largest blue whale is 1904, near the Falkland Islands in the Atlantic Ocean. This blue whale is 33.5 meters long and weighs 195 tons, which is equivalent to the weight of 35 elephants. Its tongue weighs about 3 tons, its heart weighs 700 kilograms, its lung weighs 1500 kilograms, its total blood weighs about 8 tons to 9 tons, and its intestines are half a mile long. Such a big body can only live in the vast ocean. The blue whale is the number one beast on the earth, and it can be called the "king" of all animals. The blue whale is also a unique Hercules. The power of a big blue whale can reach 1700 horsepower, which is comparable to that of a locomotive. It can tow an 800-horsepower boat, and even when the boat is upside down, it can still travel at a speed of 4 nautical miles to 7 nautical miles per hour for several hours. Blue whales also swim very fast, reaching 15 nautical miles per hour. The blue whale has a flat and wide horizontal tail fin, which is the driving force of its progress and the elevator that fluctuates up and down. Two flippers evolved from forelimbs constantly change direction,

Sperm whales are heavy-headed and light-tailed, just like a giant tadpole.

The head occupies a third of the whole body and looks like a big box. The nose is also very special, only the left nostril is smooth, located in the upper left front; The right nostril is blocked, so when it exhales, the fog column is sprayed to the left and front at an angle of 45. Although the sperm whale's teeth are more than 20 centimeters long, with 40 to 50 teeth on each side, only the mandible has teeth, while the maxilla has only holes "pierced" by the mandibular teeth. However, the habits of sperm whales are completely different from those of blue whales. It is more powerful than the blue whale, and once its prey is bitten, it is difficult to get away. Its favorite food is the deep sea king squid. Of all cetaceans, sperm whales dive the deepest, reaching 2200 meters. Sperm whales have high economic value. The huge "head box" contains a special kind of whale wax oil, which was mistakenly thought to come out of the brain, so it was called "brain oil". Actually, "brain oil" has nothing to do with the brain. This is a very useful lubricating oil. Many precision instruments, such as watches, astronomical clocks and even rockets, are inseparable from the oil contained in the head of large sperm whales. The famous Long Xianxiang is a foreign body in the intestine of this whale, and it is an excellent fragrance retention agent, hence the name of the sperm whale.

Black whales also belong to toothed whales. It is nearly 10 meter long and weighs 7-8 tons. The female is slightly smaller, and there are also 6-8 meters of killer whales who are bold, cunning and cruel and greedy. They are "lawless thugs" in the sea of Wang Yang. The English name of killer whale means killer whale. Many people have witnessed the thrilling scene of killer whales attacking dolphins, sea lions and big whales at sea. Killer whales have a big mouth, and there are more than 20 sharp teeth with a length of 10 cm ~ 13 cm on the upper and lower jaws. The mouth is wide, showing sharp teeth, which makes it more fierce. The teeth bend inward and backward, and the upper and lower teeth are staggered, similar to the shape of people's hands and fingers crossing together. This not only allows the captured things to escape from the jaws of death, but also tears and cuts the prey. Black whales are easy to identify. There are two oval white spots behind its eyes, which look like two big eyes from a distance; It also has a white area protruding backward on its side, which makes it unique. Black whales are strong and agile, and can swim fast, with a speed of 30 nautical miles per hour.

The shape of toothed whales varies greatly, with the smallest species being only about 1 m and the largest being more than 20 meters. There are conical teeth in the mouth, but the shape and number of different kinds of teeth are also very different. The least is 1 single tooth, the most is dozens, and some are hidden in gums, so it is also one of the important bases for classification. There are only 1 external nostril, so only one stream of water can be ejected when breathing. The skull is asymmetrical left and right. There are five fingers on the flippers. The sternum is bigger. No collarbone. No cecum. They mainly feed on squid and fish, and some can prey on large animals, such as seabirds, seals and other whales.

Dolphin is also a small toothed whale. Seals are round, spindle-shaped, mottled in color, with sparse fur and thick subcutaneous fat, and look fat. The hind feet always extend backward, just like the flippers of a diver. When you start swimming, your feet swing left and right in the water, pushing your body forward quickly. From the head of a seal, it looks like a domestic dog, so many areas call it a seal. Sometimes it climbs to the rock, and then its movements are particularly clumsy, and its swimming limbs can only play an auxiliary role. The crawling action of seals is very interesting, so it often causes laughter from the audience. Seals are very small, only 1.5m ~ 2.0m long. The maximum individual weight is 150kg, and the female is slightly smaller, weighing about 120kg. Under natural conditions, seals sometimes wander in the sea and sometimes go ashore to rest. When landing, choose the sandbar in the inner bay and the rocky reef on the shore that can be submerged by high tide. For example, in China, a large number of seals are frequently seen at the mouth of Panshan River in Liaoning and miaodao islands in Shandong. Seals have high diving ability. Generally, you can dive to 100 meters, 300 meters in deep water and last for 23 minutes. Its swimming speed is also very fast, generally up to 27 kilometers per hour. Seals mainly prey on all kinds of fish and cephalopods, and sometimes they also eat crustaceans. It eats a lot. A seal weighing 60-70 kilograms eats 7-8 kilograms of fish a day. However, the hind limbs of seals are constantly extending backward and cannot bend forward, so they cannot walk on land.

Sea lions roar like lions, and individual species have manes on their necks, which are quite like lions, hence the name. Its four feet are like fins, which is very suitable for swimming in the water. The sea lion's hind legs can bend forward, so that it can not only walk flexibly on land, but also squat on the ground like a dog. Although sea lions sometimes go ashore, the ocean is their real home. Only in the sea can they catch food and avoid the enemy. Therefore, most of the year, they cruise the sea for food. Sea lions mainly feed on cephalopods such as fish and squid. It has a large appetite, such as the stout northern sea lion, which can feed up to 40 kilograms of fish a day and swallow 1.5 kilograms of big fish at a time under breeding conditions. Under natural conditions, the daily feed intake is 2-3 times higher than that under feeding conditions.

There is a marine animal called Dugong, which lives in the coastal areas of China, Guangdong, Guangxi, Taiwan Province and other provinces. Its name is directly transliterated from Malay, and some people call it "Nanhai Niu". The biggest difference between it and other animals in the order manatee is that the tail of manatee is round, while the tail of dugong is similar to that of dolphin. Besides China, dugong is also distributed in some countries around the Indian Ocean and the Pacific Ocean. Some people say it is a mermaid in the ocean. Dugong is the only herbivorous mammal in the ocean, and it is not fierce at all. Dugong feeds on succulent aquatic plants such as seaweed and aquatic plants, and also eats rushes and grasses containing fibers, but it can basically eat all aquatic plants. Dugong consumes more than 45 kilograms of aquatic plants every day, so it spends a lot of time on food intake. Dugong is about 3 meters long and weighs about 400 kilograms. It moves slowly and never leaves the coast. Its swimming speed is not fast, generally about 2 nautical miles per hour, even when it escapes, it is only 5 nautical miles.

Reptiles are warm-blooded animals covered with horny scales and breed on land. Among them, turtles and sea snakes are related to the ocean.

Sea snake is a poisonous snake that lives in the sea. The nostrils of sea snakes are upward and have valves that can be opened and closed. After inhaling air, it can close its nostrils and dive into the water 10 minutes. The body surface is covered with scales, and under the scales is thick skin, which can prevent seawater infiltration and body fluid loss. The salt glands under the tongue have the function of expelling excess salt that enters the body with food. The small sea snake is half a meter long, and the big sea snake can reach about 3 meters. They live in coastal waters, especially saltwater estuaries, and feed on fish. Except for a few sea snakes that lay eggs, all others give birth, not viviparous.

Turtles are the general term for turtles. Turtles are the largest reptiles in the marine world today. Among them, the largest individual is leatherback turtle. It can be up to 2.5 meters long and weighs about 1000 kg, so it is called the King of Tortoise. The ancestors of turtles appeared on the earth more than 200 million years ago. Ancient turtles and powerful dinosaurs experienced a prosperous period together. Later, after vicissitudes of life, dinosaurs became extinct and turtles began to decline. However, under the protection of the hard shell, the turtles overcame countless bad luck brought by nature and survived tenaciously.

The main respiratory organ of fish living in water is gill. Fish leave water, dry cheeks, stick to each other, stop breathing, and stop life. The mudskipper is about 10 cm long, with a slightly flat side. The eyes above the head are like those of a frog, and the field of vision is wide. Its gill cavity is very large, and its gill cover is sealed, which can store a lot of air. The epidermis in the cavity is covered with vascular network and plays a role in breathing. Its skin is also covered with blood vessels, and blood can directly exchange gas with air through extremely thin skin.

. These unique physiological phenomena enable them to live in the air for a long time without water. In addition, the left and right ventral fins of the mudskipper are fused into a sucker shape, which can be adsorbed on other objects. The developed pectoral fin is arm-shaped, much like the appendage of higher animals. When it is attacked by the enemy, it moves faster than people walk. In order to catch food at low tide, mudskippers living in tropical areas often jump around on the beach and prefer to climb to the roots of mangroves to catch insects. Therefore, people call it a "tree-climbing fish"

"Devil fish" is a huge tropical fish, whose scientific name is manta frontalis. Its size and strength often make divers afraid, because as soon as it gets angry, as long as its powerful "wings" beat, it will break people's bones and kill people. So people call it "devil fish". Sometimes manta rays will hang themselves on the anchor chain of the ship with their head fins and drag the ship around the sea quickly, making fishermen mistakenly think that this is a "devil", but it is actually a practical joke of manta rays. Devil fish like to swim in groups. Sometimes they dive to the bottom of the sea, and sometimes they surface in pairs. During the breeding season, manta rays sometimes beat the water with their double fins, jump into the air, jump out of the water, and "slide" more than one person on the water. When falling into the water, the sound is like a cannon, stretching for miles, which is very spectacular. Manta rays look daunting, but in fact they are very gentle and only feed on crustaceans or groups of small fish and shrimp. It has two fleshy feet on its head, and these are its head fins. The head fin turns forward and protrudes freely. Manta rays use these head fins to drive away food and then swallow it into their mouths.

There is a torpedo that can generate electricity in the vast ocean, and its generator is mutated from branchial muscles. There is an oval honeycomb generator on the back of the head and the pectoral fin on the shoulder. The most basic structure of each power generation organ is a small plate-electric plate (fibrous tissue). About 40 electric plates overlap up and down to form a hexagonal cylindrical tube with 600 tubes on each side, which is called an electric function tube. It is filled with colloid, so it is translucent and milky white to the naked eye, which is obviously different from the surrounding pink muscles. One side of each plate with nerve endings is a negative electrode and the other side is a positive electrode. The current direction is from the abdomen to the back, and the discharge amount is 70 volts to 80 volts, sometimes reaching 100 volts, and the discharge is 150 times per second. When people dissected torpedoes, they found that eels, flounders and salmon were intact in their stomachs. This is because torpedoes expel active fish and then swallow them. Therefore, torpedoes are known as "underwater electric shock hands". In addition to torpedoes, the power generation organs of sting ray, thunder star, thunder roar and thunder China are relatively weak. The Warstar Fish generator is located behind the eyes, oval, and can generate 50 volts. And electric eels.

Many fish make all kinds of amazing sounds. For example, Ji Kang eel will make a "woof" sound; The electric catfish sounds like a cat's anger; Box bream can make dogs bark; Cockroaches sometimes sound like pigs, sometimes like groans, sometimes like snoring; The hippocampus will make a monotonous sound like a drum. Rock fish is famous for its beautiful sounds, such as rolling, drumming, hummingbirds flying, cats meowing and whistling. Their calls are particularly common in breeding and are aimed at clustering. Most of the sounds made by fish are caused by bone friction and contraction of swim bladder, and some are made by breathing or anal exhaust.

In the vast ocean, sharks known as "sea overlord" are all over the world. Most sharks are beneficial and harmless to human beings, and only more than 30 kinds of sharks will attack humans and ships for no reason. Sharks have a bad reputation for eating people, but not all sharks eat people. Shark's nostrils are located in front of the ventral mouth of the head, and some nostrils have nose-mouth grooves, and the nose-mouth angles are connected. The folds of olfactory sac increase the contact area with the external environment. According to the measurement, the total area of the olfactory membrane of a shark with a length of 1 meter can reach 4842 square centimeters, so the shark's sense of smell is very sensitive. It can smell blood several kilometers away. Once animals in the sea are injured, they are often attacked by sharks and die. Sharks usually only eat live food, and sometimes they eat carrion. The food is mainly fish. Dolphins, waterfowl, turtles, crabs and various fish were found in the stomach of ferret sharks. A very large sea lion was taken out of the stomach of a man-eating shark; The food of hammerhead sharks is fish and crabs; The diet of nurse sharks and star sharks is mainly small fish, shellfish and crustaceans. When sharks are looking for food, there are usually one or more sharks swimming in the water. Once they find the target, they will quickly attack and swallow it. Especially when a ship or plane crashes and a large number of baits fall into the water, they come in droves. Sharks in a state of excitement and frenzy will eat almost everything they encounter, and even kill each other for food. Sharks belong to cartilaginous fish and have no swim bladder. The regulation of ups and downs mainly depends on their big livers. For example, a 3.5-meter-long great white shark found in the southern hemisphere has a liver weighing 30 kilograms. Scientists' research shows that shark's liver depends on the increase or decrease of diacylglycerol ether, which is much lighter than ordinary triglyceride, to adjust buoyancy.

When people see butterflies flying on land, they will be full of praise. Butterfly fish is famous because it looks like a beautiful butterfly. If people want to choose beauty among coral fish, then butterfly fish is the most colorful and thought-provoking one. Butterfly fish valley, known as tropical fish, is a small warm-water coral reef fish offshore, the largest of which can exceed 30 cm, such as butterfly fish with fine lines. Butterfly fish is suitable for shuttling back and forth between corals, and can quickly disappear into coral branches or cracks in rocks. Butterfly fish has a long snout and a small mouth, which is suitable for reaching into coral caves to catch invertebrates. Butterfly fish live in colorful coral reefs and have a series of skills to adapt to the environment. Its gorgeous body color can change with the change of surrounding environment. There are a large number of pigment cells on the body surface of butterfly fish, which can expand or contract under the control of the nervous system, thus making the body surface appear different colors. Usually it takes a few minutes for butterfly fish to change their body color, while some only take a few seconds. Many butterfly fish have very clever camouflage. They often hide their true eyes in black stripes that pass through their heads, and leave a very striking "false eye" behind the tail stalk or dorsal fin, which is often mistaken for their heads, thus confusing predators. When the enemy attacked its "artificial eye", the butterfly fish flapped its fins and ran away. Butterfly fish are faithful to love, mostly in pairs, like terrestrial mandarin ducks. They swim and play in the coral reef in pairs, always inseparable. When one tail eats, the other tail will be alert around it. Butterfly fish, because of its bright body color,

The beautiful coral reefs attract many marine animals to settle here. According to scientists' estimation, a coral reef can support 400 kinds of fish. In the complex marine environment where the law of the jungle prevails, the discoloration and camouflage of coral fish are aimed at making their body color similar to the surrounding environment, reaching the point of being confused with the surrounding objects, and winning their place in the tenacious competition of hundreds of millions of creatures. Spinibarbus, commonly known as angelfish, is the most gorgeous fish among lobsters. Because they live in a darker environment than butterfly fish, they need to show more vivid colors. Many of them, in the process of metamorphosis and development of young fish, the shape and color of young fish and adult fish are completely different, and the same fish is often easily mistaken for two kinds of fish. The body of crucian carp is khaki, with eight blue-purple horizontal bands on the side and black edges. It looks like a terrestrial zebra, commonly known as zebra fish. Another kind of angelfish, its pattern is like a bug, and its black coarse pattern cleverly disguises its eyes. If you don't look carefully, it's hard to find that this is a fish. Groupers don't like to travel far. They like to live in caves or under coral branches of coral reefs. They are experts in make-up, and they can have eight body color changes, which are often completely different in an instant. They have spots and ribbons that match the environment. They watched through the cracks. When there is something edible, they will prey on rough snapper wrapped in light powder. Most of them feed on seaweed, and their body color is similar to that of seaweed. There is a protruding bone on the tail handle of their bodies, which is like a scalpel and is their survival weapon. They often beat the enemy with their tails, causing serious injuries. There is often a cockroach in the seaweed of coral reefs. Its body color and posture are similar to those of the surrounding algae, and it hides all its body in the algae, revealing only the kissing tentacles evolved from the first dorsal fin. The tentacles are long and sharp, like "bait" to lure small fish and shrimp to become ugly when they are beautiful. In coral reefs, there is a kind of rose poison, which looks terrible, with dark body color and red spots. It is often hidden in coral reefs or seaweed, just like a reef or a mass of seaweed on the seabed. When a small fish or shrimp swims near it and is stung by its back spine and head spine, it will die immediately and become its food. It is the most poisonous poison. If it is not rescued in time, people will die within 4 hours. The leaf hippocampus, which lives in algae, has various leaf-like processes similar to algae. If you don't observe carefully, you will think it is algae! Batfish living between tropical mangroves are often like a red leaf, often floating lazily in the water or pretending to be dead. People mistakenly think it is a red leaf, but as long as you touch it, it will swim away quickly. Clownfish on the reef often live with anemones, and colorful clownfish often go out to attract other small fish and shrimp. These small fish and shrimps are paralyzed by stinging cells in the tentacles of anemones and then swallowed into their mouths. Once in distress, clownfish will get into the tentacles of sea anemones and become an ideal shelter for protection.

All night, fish lamps and shrimps were burning brightly. It is they who bring light to the deep sea without sunshine and the sea covered by night. In fact, at least 44% of the fish in the dark layer have their own luminous ability, which enables them to see other objects in the long night, which is convenient for hunting and finding companions and spouses. Some fish can emit light, such as hairtail and dragon head fish in the southeast coast of China, which are emitted by luminescent bacteria attached to their bodies, while more fish are emitted by their own luminous organs. Candlelight fish have rows of luminous bodies on their abdomen and ventral side, just like rows of candles. Therefore, this bald fish named Candlelight Fish has a flat back and is covered by a pair of huge luminous bodies, which may have played a visual role. Fish luminescence is a special biochemical reaction caused by enzyme catalysis. Luminous fluorescein is catalyzed by luciferase, which absorbs energy and becomes oxidized fluorescein, releasing photons and emitting light.

Maura is very strange. Its body is short and flat, its dorsal fin and anal fin are relatively high, and its caudal fin is very short, which looks like it was cut by a knife. Therefore, its common name is also called head fish. Molas swim very slowly. It lives in the tropical ocean, and many luminous animals often attach themselves around its body. As soon as it swims, the luminous animals on it will emit bright light, which looks like a bright moon from a distance, so it is also called "moon fish". Mola, a top-heavy body, is very suitable for diving. It often dives into the deep sea to catch deep-sea fish and shrimp for food. Molas are clumsy and not good at swimming, and are often eaten by other fish and marine animals in the ocean. The reason why it won't become extinct is because it is very fertile. A female fish can lay 300 million eggs at a time, which makes it the most fertile fish mother in the ocean. Molas are found all over the world, and there are three kinds of molas along the coast of China, namely molas, molas with yellow tail and molas with spear tail.

Edit this paragraph. Arthropods wear helmets and armor.

Arthropods are the largest kind of animals, accounting for about 85% of more than 654.38+0 million known animals. This animal's body is divided into three parts: head, chest and abdomen, and its appendages are segmented, hence the name arthropod.

Horseshoe crab (horseshoe crab) looks like both shrimp and crab, and it is an animal as old as trilobites (only fossils now). The ancestors of horseshoe crabs appeared in the Paleozoic Devonian in geological history, when dinosaurs had not yet risen and primitive fish had just come out. With the passage of time, its contemporaries have either evolved or become extinct, but only horseshoe crabs have retained their primitive and ancient appearance since they came out more than 400 million years ago, so horseshoe crabs are called "living fossils". In the breeding season of horseshoe crabs in spring and summer, once married, it is difficult for men and women to give up, and obese female crabs often stumble with their thin husbands. At this time, I caught a horseshoe crab, which is a pair when I mention it, so horseshoe crab enjoys the reputation of "Yuanyang under the sea". Horseshoe crabs have four eyes. There are two small eyes of 0.5 mm at the front end of the head breastplate, which are the most sensitive to ultraviolet rays, indicating that these eyes are only used to perceive brightness. There are a pair of big compound eyes on both sides of horseshoe crab breastplate, and each eye consists of several small eyes. It is found that the compound eye of horseshoe crab has a lateral inhibition phenomenon, which can make the image of the object clearer. This principle has been applied to TV and radar systems, which improves the clarity of TV imaging and the display sensitivity of radar. In addition, the meat and eggs of horseshoe crabs are edible.

Shrimp and crab are another family of arthropods, all of which belong to the Decapoda of Crustacea. There are also many kinds of crabs living in the sea of China, such as the tender and delicious Portunus crab, the sand crab that walks like a fly, the coconut crab that can climb trees, and the Guan Gong crab that looks like Guan Gong's face with nail grooves on its back. However, the king of crabs is a tall crab living in the Sea of Japan and the Bering Sea. The body of the high-legged crab is more than 30 centimeters long, one leg is about 1.5 meters, and the legs on both sides are almost 4 meters straight and weigh about 7 kilograms. It is the largest crab in the world. People only know that the meat of shrimp and crab is delicious, but it is a great waste to abandon its shell. You know, shrimp and crab shells can extract many useful things. For example, the shells of shrimps and crabs can be used to make good textile pulp. The pulp made of "shrimp skin and crab cover" is bright in color, not easy to be washed off by water, low in cost and can save a lot of flour.

When we come to the seaside, we may meet a strange little crab. The two claws of a crab are very asymmetrical. One is thick and big, and the other is thin and small. Whenever the tide recedes, it climbs out of the cave and runs back and forth on the beach above the water for food. Whenever the tide rolls up and is about to submerge the nest, it hides in the cave again, holding its strong paws high at the mouth of the cave as if waving to welcome the arrival of the tide, so people call it "fiddler crab". The body color of this crab can change day and night. During the day, it is dark. If you look at it under a microscope, you can see that the pigment in its cells spreads everywhere, just like a big black umbrella.

In the intertidal zone by the sea, you can often catch a kind of crab. Its head and breastplate look like Guan Gong's face in Beijing Opera, and its name is Guan Gong Crab. Guan Gong crab often grabs stones or leaves to cover its body, so as to cleverly disguise itself and avoid the enemy. Spider crabs are ugly. Why wear some gorgeous flowers on the breastplate or big pincers? No, that's not a flower. That is a kind of anemone, commonly known as "sea chrysanthemum". Spider crabs rely on poisonous anemones on their tentacles to protect themselves from enemies and beautify their ugly bodies. There is a sponge that often attaches to the shell of hermit crab. There are shells everywhere in Shanghai, leaving only the mouth of the shell for hermit crabs to enter and leave freely, relying on the stench secreted by this sponge to defend against the enemy. Flat back and abdomen, wearing helmets and armour all over, colorful, very beautiful, with a pair of big claws resembling mantis, commonly known as "mantis shrimp". Seeing the shrimps watching the movement quietly at the bottom of the sea in the middle of the night, waiting for their prey, people will think of liger lying on the hill just waiting to jump up. Squid usually likes to make holes in the muddy shallow seabed, and often only shows its head to observe the enemy. Once the prey comes near, it will stretch out its pliers and attack quickly. It can snap its prey in two, showing its fierce and cruel face. It is not only good at "grabbing by force", but also knows how to "take advantage of it". It often turns its cave into a hidden place, and even painstakingly moves sand and stones from a distance to build several circuitous passages next to the sand cave where it lives. Once the underwater animals break in, it's like being trapped in a maze. Frog crab looks like a frog. It often buries itself in the sand, showing only two eyes to observe the movement and look for food.

When we walk by the sea, we will see clusters of small animals with gray-white and calcareous shells on the rocks. These small animals are another branch of the arthropod family, called barnacles. Barnacles are shaped a bit like horse teeth, so people who live by the sea often call them "horse teeth". Barnacles are not only attached to rocks, but also can be fixed on the hull, and will not be washed away under the impact of wind and waves.

Starfish is a class of echinoderms, which is divided into two families: petrels and starships. Starfish, sea cucumbers and sea urchins belong to echinoderms. They usually have five wrists, but there are also four or six, and some have as many as 40 wrists. There are four rows of pins under these wrists. Using pins can not only catch prey, but also let yourself climb on rocks. Sea star has thousands of tube feet. Starfish's mouth is in the middle of its lower body, which can directly contact the surface of the object that starfish has climbed. Starfish vary in size, ranging from 2.5 cm to 90 cm, and their body colors are different. Almost every one is different, and the most common colors are orange, red, purple, yellow and cyan. Starfish are mainly distributed in shallow seabed sand or rocks all over the world. Because starfish can't move as flexibly and quickly as sharks, its main prey are some slow-moving marine animals, such as shellfish, sea urchins, crabs and anemones. It often adopts a slow and tortuous strategy, slowly approaching the prey, grasping the prey with the tube foot on the wrist and wrapping it all over, spitting out the stomach bag from the mouth, dissolving the prey in vitro with digestive enzymes and being absorbed by it. This starfish eats shellfish. When starfish want to eat mussels, they will first open their shells with powerful suction cups, and then stick out their stomachs to eat mussels. Therefore, the economic value of starfish is not great, and it can only be dried and ground into powder for agricultural fertilizer. Because it preys on shellfish, it is very harmful to shellfish culture. Starfish are echinoderms that live in the sea. They are very fertile. In addition, starfish has a special ability-regeneration. Starfish can regenerate naturally after their wrists and body plates are damaged or cut by themselves. Any part of a starfish can be regenerated into a new starfish. Therefore, some species of starfish have evolved the ability of asexual reproduction through this super-regeneration method, without mating. But most starfish usually don't reproduce asexually.

Sea urchin is another member of echinoderms family. It has a round calcareous hard shell and is equipped with hard thorns.

Coelenterates belong to lower metazoa in taxonomy. Vertebral cells are unique to coelenterates, and they are all over the body surface. On the tentacles, especially the sea moon jellyfish has an umbrella-shaped bell-shaped body, which floats on the sea like a bright moon and falls into the sea, which is very beautiful. The jellyfish is in the shape of a monk's hat, with tentacles covered with countless small stinging cells, and the venom of the stinging cells is similar to that of cobra.

Chrysanthemums on the land bloom in autumn, but in the foggy sea, there is a kind of "sea chrysanthemum" that blooms all the year round. It is a kind of anemone with various shapes, generally cylindrical and colorful, and its base is attached to rocks, shells, gravel or seabed. At the top of the anemone is a round plate, surrounded by several to thousands of chrysanthemum petal-shaped tentacles, which swing with the waves in the water, opening and closing like flowers. Anemones living in reef disks, ants have sky blue and yellow tentacles, forming a bright "flower cluster". Fish and shrimp compete to play in the "flowers". Once they are stung by the stinging cells on the antenna, they will be paralyzed all over, and finally they will be caught in their mouths by the antenna and become a delicious meal. Only brightly colored clown fish can coexist with it and benefit each other. Some biologists believe that the life span of anemones is as long as 300 years, so this kind of "sea chrysanthemum" can bloom for 300 years without thanks, which is incomparable to terrestrial chrysanthemum flowers.

Scientists call algae that inhabit the seabed benthic algae. They live in the temporary "freezing" of drought and winter. As long as the sea water rises, they start to grow and develop normally again. Most benthic algae are multicellular algae visible to the naked eye. The adults of races are only a few centimeters long, such as filamentous algae; Up to 200 ~ 300 meters long, such as giant algae. Benthic algae have strange shapes: some are like belts, such as kelp; Some are like ropes, such as chordates; Some are flaky, such as Ulva and laver; Some are dendritic, such as Sargassum. Some benthic algae have only a thin layer of cells, such as reef membrane; Some have two layers of cells, such as Ulva; Some are hollow and tubular, such as Enteromorpha; Other algae can be divided into outer cortex, cortex and pith, such as kelp and Sargassum. Benthic algae are bright and beautiful in color, including green, brown and red. Scientists divide algae into three categories according to their colors: green algae, brown algae and red algae.

The body of green algae is grass green. There are about 6,000 species of green algae, 90% of which are produced in fresh water, and only 10% live on rocks in intertidal or subtidal zones. Green algae have single cells and colonies; Filamentous,