Great white sharks are distributed in tropical and temperate regions of various oceans, generally living in open ocean areas, but often entering inland waters. Their favorite prey are seals and sea lions, and occasionally they eat the carcasses of dolphins and whales.
Great white shark first appeared in Miocene, and it is the only surviving member of the genus man-eating shark. Therefore, its survival is very difficult. It can be said that the existence of every great white shark is a miracle of life evolution, just like dinosaurs in Cretaceous. Due to the decreasing number of great white sharks, which are on the verge of extinction, great white sharks have been listed as world protected species and hunting is prohibited. Because of its size and aggressiveness, it is considered as a marine killer and has been made into movies and games of the same name.
There is no subspecies differentiation. Shape feature listening to speech
The adult great white shark has an average body length of 4 ~ 5.9 meters and an average weight of 2000 kilograms. The largest known great white shark is 7.2 meters long and weighs 3200 kilograms. The female is bigger than the male. It has black eyes, fierce teeth and double jaws, which is very similar to piranha. Generally, it is gray, light blue or light brown, with pale white abdomen, well-defined back and abdomen, and light body. The body is heavy, the tail is crescent-shaped, the teeth are large and triangular, and the edges are serrated. Among all sharks, the great white shark is the only one that can stand upright on the water, which gives them the advantage of finding potential prey on the water. [1] Great white sharks can also dive to a depth of 1200m.
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Morphological map of great white shark
Vision: Most great white sharks are a little farsighted, with focal lengths ranging from about 23 cm to infinity. In addition, great white sharks have a diaphragm above their eyes, and when their eyes turn inward, they roll their eyes. This can protect the eyeball from prey.
Hearing: The inner ear of the great white shark is located on both sides of the brain, and the internal lymphatic vessels are connected with two holes in the scalp. Both ears have small ducts leading to the sensory holes on the top of the head. The receiver in the inner ear also has the same function as the lateral line, and can receive acoustic vibration with a distance of 1 ~ 2km. Experiments show that the auditory system of great white shark can feel 10 Hz to 800 Hz, with an average response of 375 Hz. Although the hearing of sharks is similar to that of humans, sharks can hear and perceive sounds that many people can't hear, and sharks are more suitable for capturing low-frequency vibrations, such as dying fish.
Smell: The olfactory bulb nerve organ of great white shark accounts for 14% of brain volume, and can distinguish a serine molecule of 1 0 from15 water molecules. It can smell blood diluted to the original concentration of 1/500 kilometers away.
Touch: the lateral line of the great white shark is composed of some sensory organs at the bottom of the nest. Each sensory organ has a small hole leading to the outside of the skin, which is used to feel the vibration of water flow and detect the existence of prey particles, with a distance of 500 ~ 600 meters. These sensory organs extend in the same direction along a very thin tube under the skin and are separated below the mouth, and this thin tube will have another microchannel leading to the outside at regular intervals. On the other hand, the great white shark has many tiny pores around its nose and mouth, which is called "Loren magnetic pot". It is a deep channel, rich in colloid and very sensitive to the changes of electricity, temperature and water pressure. Its function is to act as an electro-receptor to stop the weak electric field changes around it, and to receive the weak telecommunications of prey in the water in order to find hidden prey or its movement. At the same time, the "Loren Magnetic Pot" system can also determine the position in the electromagnetic field of the earth, and has certain navigation ability. [2]
Teeth: In the jaws of the great white shark, there are 26 sharp teeth arranged in the upper jaw, and there are barbs on the back of the teeth, so it is difficult for the prey to break free after being bitten. Once any tooth in front of the great white shark falls off, the extra teeth in the back will move to the front to supplement it. At any time, about one-third of the teeth of great white sharks are in the process of replacement. [3]
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Great white shark's teeth
Skin: Great white shark's skin is extremely lethal. "Shark skin" is not smooth. Although there is no scale, it is covered with small barbs, which is rougher than sandpaper. Even if the prey is hit by it, it will bleed profusely.
Body temperature: the body temperature of fish living in water is usually the same as the surrounding water temperature, but the body temperature of great white shark is much higher than the surrounding water temperature, up to 15℃. High body temperature can help them swim faster and help them digest better. [ 1][4]
Listen to the speech at home
Great white sharks mostly inhabit near the water surface, with a water depth of 3-300m, sometimes dropping to a depth of 700m or 1000m, and sometimes coming to the offshore shallow water area. [ 1]
Living habits of listening to pronunciation
characteristic
Great white sharks belong to a few semi-warm-blooded animals. The blood at the end of their bodies is close to the flowing blood, which keeps them at a temperature of 23 to 26 degrees Celsius, which enables them to maintain a body temperature higher than the ambient temperature, which enables them to live comfortably in very cold seawater. Although it is hard to see in most coastal areas, fishing boats and diving boats often meet unexpectedly. [4]
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Great white shark
Eating habits
Great white sharks like to prey on fish, turtles, seabirds, sea lions, walrus seals of similar weight, and even giant baleen whales that are dying. They occasionally eat dolphins, whale carcasses and even other sharks, but in addition, they also eat many other things, such as sea otters and dead fish floating on the sea. [5]
Looking for food
Great white sharks have an extremely sensitive sense of smell and touch. It can smell blood diluted to the original concentration at a distance of 1/500 kilometers, and drive away at a speed of 69 kilometers per hour. It can also detect the tiny current generated by the contraction of biological muscles, so as to judge the size and movement of prey.
Meanwhile, great white sharks are good at hunting. In order to effectively catch prey, great white sharks usually take the form of surprise attack. They will ambush at the bottom of the water first. Because the back of the great white shark is dark, it is difficult for seals to detect the existence of the great white shark on the water. After the great white shark confirms its prey, it attacks from the bottom up. Generally speaking, the first attack will seriously hurt the prey. At this time, the great white shark will stop any attack until the prey bled to death, and then enjoy the prey in a gentle way. When the prey moves at high speed, the great white shark even jumps out of the water to attack the prey. [ 1]
attack
Great white sharks are considered to be more harmful to people than other sharks. They are notorious for sometimes making deadly attacks on swimmers, divers, surfers and even boats without stimulation. It has caused the greatest number of deadly attacks on human beings, especially on surfers and divers. Some studies have also found that many attacks attributed to great white sharks are actually caused by bull sharks, not all great white sharks.
Great white sharks are also famous for their curiosity-they often look up from the water, they often explore unfamiliar targets by biting, and they also swallow everything they are interested in: meat, bones, wood blocks, and even pens and glass bottles. Their stomachs have a hard wall so that what they swallow won't hurt them. [6][ 1]
Reproduction mode of listening to sound
Great white sharks are oviparous, the gestation period is about 12 months, and each nest has 2 ~ 10 cubs. The newborn shark is more than 1 meter long. The age of sexual maturity is 10 for males and 12 to 18 for females. Moreover, the life span of great white sharks is very long, reaching about 70 years old, which is equivalent to that of humans. [7][6]
The distribution range of listening voice
Country: Albania, Algeria, Australia (northern South Australia), Bahamas, Barbados, Bosnia and Herzegovina, Brazil, Chile, Croatia, Cyprus, Egypt, France, Gibraltar, Greece, Israel, Italy, Japan, Kenya, Lebanon, Libya, Madagascar, Mauritania, Mauritius, Montenegro, Morocco, Mozambique, Namibia. Philippines, Seychelles, Slovenia, South Africa, Spain, Sri Lanka, Syrian Arab Republic, United Republic of Tanzania, Tunisia, Turkey, United States (California, Hawaii, Oregon), Western Sahara.
Great white shark distribution map
Waters: West Atlantic, Middle East, Southwest, Southeast and Northwest; West, East, Mediterranean and Black Sea of Indian Ocean; Southeast, Northeast, Northwest, Middle East, West and Southwest of the Pacific Ocean. [9]
The status of species, listen to the sound.
Great white sharks are at the top of the marine food chain, and few other creatures can pose a threat to them. Besides humans, killer whales (also known as killer whales) are the only creatures that can kill great white sharks. Black whales and great white sharks are both top predators in the ocean.
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Great white shark
Qian Qian people who live by the sea think that sharks are a cheap source of protein. Sharks are usually cut off after being caught and then thrown back into the sea while the remains are still alive. Trade in shark products: shark fin, fish, fish liver and other parts are sold as food and beauty products, among which shark fin is the most common, and the price is 564 US dollars per kilogram. As many as 125 countries participate in the trade of shark products. Only the United States and Mexico caught as many as100000 tons of sharks in 1944, which is regarded as the top two shark catching countries in the world. 98% sharks are killed for their fins and meat to meet the huge increase in demand for shark fin soup. Fins only account for 1% to 5% of the whole shark body, and the other 95% to 99% are discarded.
Due to the low birth rate of sharks, the population has been unable to recover, resulting in a sharp decline in the global population. According to researchers' calculations, the number of great white sharks in the world is less than 3,000, which is less than the number of wild tigers. [ 10][9]
Species protection Listen to the lecture.
Australia, Mexico, New Zealand, South Africa and the United States. The Food and Agriculture Organization of the United Nations has prepared an international action plan for the protection and management of sharks. Through scientific discovery, great white sharks regularly migrate across borders, which highlights the necessity of international protection measures. [ 1 1]
20 1 1 On September 22nd, 2008, the international environmental protection organization wildaid Association, together with its shark protection ambassadors-international sports stars Mr. Yao Ming and Yao Fund, joined hands with Sir richard branson, president of Broad Group, British entrepreneur and Virgin, a non-profit organization, to hold a press conference in Shanghai Yayue Hotel, calling for the protection of endangered species sharks. Yao Ming even said that he would never eat shark fin again to protect the survival of sharks such as Great White Sharks.
Protection level of listening to sound
Listed in Appendix II of CITES Convention of Washington Convention [1 1]
It was listed in the IUCN Red List of Endangered Species in 2009, ver 3. 1- vulnerable (VU)[9].
Atlas source [12]
Listen to the pronunciation of species history
The newly discovered fossils of shark species show that the modern great white shark actually originated from the wide-toothed striped shark. The researchers said that the newly discovered species represented a possible transition from one shark to another. According to the obtained fossil samples, it is known that this shark is about 16 feet long and has 222 complete teeth and 45 spines.