The largest animal

Species: scientific name of Blue Whale: Balaenoptera musculus(Linnaeus, 1758) English name: blue whale alias: razor whale, whitefin whale Endangered information: CITES: Appendix II IUCN: Category II is the largest species of baleen whales, and the oldest is in Antarctic waters 1904 to/kloc-. Females are bigger than males, and southern blue whales are bigger than northern blue whales. Seen from above, the kiss is wide and flat. The dorsal fin is small, about 0.4m high, and 1/4 is at the back of the body. The flippers are small, accounting for 15% of the body length. The caudal fin is 1/3 to 1/4 in length, and the trailing edge is straight. There are 55 ~ 88 puncture grooves, the longest of which can reach the navel. 270 ~ 395 whiskers per side. The back of the body is dark gray-blue, the belly is slightly talked about, and the mouth must be black. Blue whales feed on plankton, mainly krill. A blue whale consumes 2 ~ 4t food every day. The swimming speed is 2 ~ 6 km/h when feeding, 5 ~ 33 km when migrating, and the maximum forced speed is 20 ~ 48 km per hour. General 10 ~ 20 dive is followed by a deep dive. Shallow dive interval 12 ~ 20 seconds, deep dive sustainable 10 ~ 30 minutes. The spray column is narrow and straight, with a height of 6 ~ 12m. The blue whale is sexually mature at the age of 10. Northern blue whales breed and mate in late autumn and early winter. The southern hemisphere mates in the south in winter, with the peak in July. The reproductive period between the northern and southern hemispheres is half a year apart. The gestation period is 10 ~ 1 1 month. The calf is 6 ~ 7 meters long and weighs about 6 tons. The lactation period is half a year, and the weaning time can reach 16m. The highest age is estimated to be between 30 and 80-90. In the world, Antarctic waters are the most effective, mainly in temperate and cold waters with water temperature of 5 ~ 20℃, and a few whales have swam in the waters of the Yellow Sea and Taiwan Province Province. Blue whale is one of the most important economic species and contains a lot of fat. Internationally, it is stipulated that the oil production of blue whales should be used as the conversion unit, that is, 1 blue whales = 2 fin whales = 2.5 humpback whales = 6 fin whales. Since modern whaling began, blue whales have been caught indiscriminately. During the peak period of 1930 ~ 3 1, nearly 30,000 blue whales were killed worldwide. 1966, the international whaling commission declared the blue whale as a protected object. Before the development, there were at least 200,000 blue whales, and now it is estimated that there are at most13,000 blue whales. According to the statistical report published by the International Whaling Commission 1989, there are only 200 ~ 453 blue whales. This is based on an eight-year survey in the southern hemisphere, which is on the verge of extinction. It is divided into the following three subspecies: middle B.M. Burmeister (1871), distributed in the southern hemisphere; The female body length of southern blue whale is 23 ~ 24m, the male body length is 22m, and the mature body length is 26 ~ 27m and 24 ~ 25m respectively. The northern blue whale (B.m musculus Linnaeus, 1958) is distributed in the North Atlantic and the North Pacific. The female body length of northern blue whale is 2 1 ~ 23m, the male sexual maturity is 20 ~ 2 1~23m, and the body length is 25 and 24m respectively. Little blue whale (B.M. Brevicaukta Ichihara, 1966) The little blue whale is distributed in the sub-Antarctic waters of the Indian Ocean and the Southeast Atlantic Ocean. When the female body length is 19m, the male body length is slightly less than 19m, and the female body length is 22 and 2 1m respectively. The blue whale is not only the largest whale, but also bigger than the largest dinosaur that has ever lived on earth. It is the largest of all known animals since ancient times. It is generally 2400-3400 cm long and weighs150,000-200,000 kg, that is, its weight is equivalent to more than 25 African elephants, that is, 2000 kg. Fortunately, because of the buoyancy of the ocean, it doesn't need to support its weight as hard as land animals, and its huge body helps to keep a constant body temperature. The whole body surface of the blue whale is light blue or mouse gray, with thin stripes on the back, white spots on the chest and more than 20 folds, and the abdomen is covered with folds all the way to the navel with ochre spots. Female animals have cleavage on both sides of the reproductive opening with slender nipples inside. The head is small and flat, with two spray holes on the top of the head, a wide mouth, no teeth in the mouth and a wide upper jaw. It bulges upward in an arc shape, with 300-400 black whiskers on each side, 90-110cm long and 50-60cm wide. A large amount of earwax accumulates in the eardrum every year, and its age can be judged according to its thickness. It also has a white callus on its upper jaw, which used to be a place for long hair. Later, the hair degenerated, leaving a warty vegetation and becoming a breeding ground for parasites. Because this callus is different for each individual, just like wearing a hat with a different shape, different individuals can be distinguished accordingly. The dorsal fin is extremely short, the length is less than 0.5% of the body length of 65438+, and the flipper limb is not too long, about 4 meters, with four toes, no wavy notch at the back edge, and a wide and flat tail. The whole body is streamlined and looks like a razor, so it is also called "razor whale". The blue whale's body is so huge, one tongue has 2000 kilograms, the skull has 3000 kilograms, the liver has 1000 kilograms, the heart has 500 kilograms, the blood circulation reaches 8000 kilograms, and the testicles of male animals also have 45 kilograms. If its intestines are straightened, it is 200-300 meters long, its blood vessels are thick enough to hold a child, its dirty wall is more than 60 centimeters thick and its penis is 3 meters long. Its power is also amazing, and its power is about 1500- 1700 horsepower, making it a well-deserved Hercules in the animal kingdom. Blue whales are distributed in the oceans of the northern and southern hemispheres from the South Pole to the North Pole, especially near the South Pole, but they are rare in tropical waters. In China, it is distributed in the Yellow Sea, the East China Sea and the South China Sea, including the waters in the south and southwest of Taiwan Province Province. Despite its huge size, it usually moves slowly and often stands still, but it can rise and fall freely in the water and its tail swings flexibly. It is not only the driving force for progress, but also acts as a rudder, with a speed of 28 kilometers per hour. Most of the bays inhabited by blue whales are flooded with extremely rich organic matter in the river water on the landing land, which makes the water quality very fertile and promotes the massive reproduction of plankton. The dense plankton attracted a large group of krill, and their bodies shone blue like diamonds. Incredibly, the blue whale, a super-large animal, actually feeds on krill, a tiny animal. Its stomach is divided into four parts. The first stomach is formed by esophageal dilatation, so it eats a lot. It can swallow 2 million krill at a time and eat 4000-8000 kilograms a day. If the food in its stomach is less than 2000 kilograms, it will feel hungry. Krill is the most abundant animal in the world, widely distributed in the Arctic and Antarctic waters. It is because there is such a rich food and there is no limit to support weight that blue whales can develop so much. Every day, it spends most of its time swimming in dense plankton. The two rows of plate-like tentacles on its mouth are like a sieve, and its belly has many folds like accordion bellows, which can be expanded and contracted, so that it can swallow seawater and krill together, and then when its mouth is closed, seawater is discharged from the tentacles, filtering out shrimp and fish and swallowing them. Blue whales eat other shrimps, small fish, jellyfish, diatoms and various plankton. In contrast, blue whales living in northern waters are smaller than those living in waters near Antarctica, which is generally considered to be closely related to the types and quantity of their food. Although blue whales live in the sea, like other mammals, they breathe with their lungs, which weigh more than 65,438+0,000 kilograms and can hold more than 65,438+0,000 liters of air. Such a large lung capacity greatly reduces the number of breaths, and only comes out to breathe once every 10- 15 minutes. When breathing, carbon dioxide and other waste gases in the lungs are discharged from the body through the nostrils, and then fresh oxygen is inhaled. Whenever its head comes out of the water to breathe, it will expel carbon dioxide and other waste gases from its body. When this powerful hot airflow rushes out of its nostrils, the jet height can reach about 10 meter, and it will also roll the nearby seawater out of the sea surface, and a spectacular water column will appear on the blue sea surface. From a distance, it looks like a fountain on the sea, and at the same time it makes a loud sound like a train whistle. People call it "jet tide". People can determine the position of the blue whale according to the sound it makes when breathing and the height and shape of the jet. Blue whales live in all oceans. It is extremely rare to see blue whales in China waters. There are records of blue whales in the Yellow Sea and the South China Sea, generally not exceeding 65,438+000 meters. However, some individuals can dive to a depth of 500 meters, and the diving time can last for 10 ~ 20 minutes, followed by 8 ~ 15 times of air jet, and the jet water column can be as high as 9. 1 meter. Generally, whales don't raise their tails before diving, but blue whales always show their tails out of the water before diving, sometimes jumping out of the water very high, and then quickly diving into the water of 30-40 meters to find food. Usually, I also like to draw water with the tail fin, which is a versatile and versatile pastime. It may be playing a game, attracting the attention of its peers, or removing parasites from its skin. Although some people have seen 50-60 blue whales move in groups, they rarely form groups, most of them are lonely, or only 2-3 of them move together. Amphibious blue whales are very harmonious with each other, swimming, diving, foraging and breathing together, just like mandarin ducks, inseparable, often leaving a wide waterway behind them. Three blue whales get together, mostly females and a calf, close together, followed by males, about 3 meters apart. Blue whales breed in winter, and females are usually born every two years. Pregnancy 10- 12 months, each fetus only gives birth to 1 child. The newborn cub is 6-8 meters long and weighs about 6000 kilograms. In order to prevent suffocation and death, the mother beast should lift her cub out of the water to take the first breath of air, and then she can breathe by herself. A pair of nipples of female animals grow on both sides of reproductive foramen, and swim in the upper layer of seawater when breastfeeding, and the young closely follow the tail of female animals. Because the larvae have no movable lips, they can't hold their nipples to suck milk. Female animals directly spray milk into their mouths by virtue of muscle contraction, which is also a good adaptation to their main activities in water. Blue whale's milk is rich in nutrition, in which the fat content is 10 times that of milk, and the milk that young whales suck every day is above 1000 kg, so it develops rapidly. After 8 months, it can be increased to 65,438+05 m and its weight can be increased to 23,000 kg, so it can eat all kinds of plankton with its own mouth. By the age of two and a half to three, the body length can exceed 20 meters. The age of sexual maturity is about 8- 10 years old, and the life expectancy is generally over 50 years old, with the highest being 90- 100 years old. Of all animals, the blue whale makes the loudest noise. Blue whales use low-frequency deafening sounds when communicating with their partners. This sound can sometimes exceed 180 decibels, even louder than the sound you hear when a jet plane takes off on the runway. Sensitive instruments have detected the sound of blue whales 80 kilometers away. Taxonomically, blue whales belong to mammals, cetaceans, fin whales and fin whales. Over the years, countries all over the world have been racing to hunt in the ocean, and now blue whales over 25 meters in length are rare. In addition, the fishing of krill has greatly affected the foraging activities of blue whales. According to statistics, there were about 300,000 blue whales in the world half a century ago. To 1974, there are still 25,000, and now there are only about 2,000 left. Although the number of blue whales killed every year has been limited internationally since 1932, the prospect of this world's largest animal is still very dangerous.