Systematics and evolution
The characteristic tooth structure and size of the great white shark and the prehistoric Megalodon have led most scientists to consider them to be closely related species. This assumption is reflected in the scientific name of the latter - Carcharodon megalodon.
Also noteworthy are the doubts currently expressed about this hypothesis by prominent scientists who position the megalodon and the white shark as distant relatives - members of the herring shark family, but not so closely related. Recent studies suggest that the white shark is closer to the mako shark than to the megaladon. According to the theory put forward, the true ancestor of the great white shark is Isurus hastalis, while megaladons are directly related to sharks of the species Carcharocle. According to the same theory Otodus obliquus considered to be a representative of an ancient extinct branch Carcharocles.
Distribution and habitats
The great white shark lives around the world in the coastal waters of the continental shelf, the temperature of which is between 12 °C (+54 °F) and 24 °C (+75 °F). In colder waters, significant colonies of sharks of this species are also found: off the southern coast of Australia, off the coast of South Africa, California, near the Mexican island of Guadeloupe. Separate populations live in the central part of the Mediterranean and Adriatic Sea (Italy, Croatia), off the coast of New Zealand, where they are protected species.
One of the most significant populations has chosen Dyer Island (South Africa), which is the site of numerous scientific studies of this species of sharks. Sometimes great white sharks are also found in warm tropical waters: in the Caribbean Sea, off the coast of Mauritius, Madagascar, Kenya and near the Seychelles.
This species belongs to the epipelagic fish, their occurrence is usually observed and recorded in coastal currents abounding in prey such as fur seals, sea lions, whales, where other sharks and other large bony fish live. The great white is nicknamed the master of the ocean, as it is capable of significant movement and can descend to pelagic areas: sharks have been recorded at depths up to 1300 m.
Recent studies have shown that the great white shark migrates between Baja California (Mexico) and a place near Hawaii known as the White Shark Cafe, where they spend at least 100 days a year before migrating back to Baja California. Along the way, they swim slowly and dive to a depth of about 900 m. After arriving at the coast, they change their behavior. Dives are reduced to 300 m and last up to 10 minutes.
A great white shark tagged off the coast of South Africa has shown a migration path to and from the southern coast of Australia every year. These studies have debunked traditional theories that the great white shark is a coastal predator. The interactions of different white shark populations with each other, which were previously considered separate from each other, have been proven. The purposes and reasons why the great white shark migrates are still unknown. There are suggestions that migrations are due to the seasonal nature of hunting or mating games. In a similar study, a great white shark swam a route from South Africa to the northwest coast of Australia and back, covering 20,000 km in less than 9 months, averaging 75 km per day.
Anatomy and appearance
The great white shark has a strong, large conical head. The width in the upper lobe and in the lower lobe (near the tail) is the same (as in most herring sharks). The great white shark is camouflaged: it is white on the underside and gray on the back (sometimes tinged with brown or blue), giving the impression of a mottled coloration that makes the shark difficult to spot, as the shark's body visually disintegrates when viewed from the side. When viewed from above, the dark shadow dissolves into the thickness of the sea, and when viewed from below, the silhouette of a shark is hardly noticeable against the background of light. Great white sharks, like many other sharks, have three rows of teeth. Great white shark teeth are serrated and when the shark bites and shakes its head from side to side, the teeth cut like a saw and tear off pieces of flesh.
Dimensions
The size of a typical adult great white shark is 4-5.2 meters with a mass of 680-1100 kg. Females are usually larger than males. The maximum size of the white shark is about 6 m with a maximum weight of about 2000 kg. The maximum size of the white shark is a hotly debated topic. Richard Ellis and John E. McCosker, recognized scientific experts on sharks, devoted an entire chapter to this subject in their book The Great White Shark (1991), which analyzes various reported maximum sizes.
For several decades, many works on ichthyology, as well as the Book of Records, named the largest two specimens: a 10.9 m long shark, caught in southern Australian waters near Port Fairy in the 1870s, and a 11.3 m long shark , caught in a herring trap at a dam in New Brunswick, Canada in 1930. Reports of the capture of specimens 7.5-10 meters long were common, but the above sizes remained record-breaking.
Some researchers question the reliability of the measurements in both cases, as these results were significantly larger than any other results obtained by accurate measurements. The New Brunswick shark may not have been a white shark, but a giant shark, since both sharks have a similar body shape. The question of the size of the Port Fairy shark was clarified in the 1970s when Gee. I. Reynolds studied the shark's mouth and found that the Port Fairy shark was about 5 meters in length. He suggested that in 1870 an error had been made in the original measurement.
Ellis and McCosker determined the size of the largest specimen, the length of which was reliably measured, in 6,4 meters, which was caught in Cuban waters in 1945. However, in this case, there are experts who claim that the shark was actually several feet shorter. The unconfirmed weight of this Cuban shark is 3270 kg
Perhaps the most dangerous and formidable predator of the world's oceans is the white shark. According to the scientific classification, white sharks belong to the chordate type, the herring family, the class of cartilaginous fish, the superorder of sharks and the order of lamniformes.
What are its characteristics, weight, length, appearance? Where does the white shark live and is it dangerous to humans? This will be discussed in detail below.
Great White Shark Carcharodon
great white shark, known to science also like carcharodon, it is a large predatory fish that lives in all waters of the world's oceans with the exception of the Arctic. This predator got its name due to the white color of the belly, which is clearly separated from the gray color of the back by a broken line.
Medium the length of the carcharodon exceeds 7 meters, and its weight is at least 3 tons. This rightfully suggests that such a fish is the largest on earth. It can compete only with whale and giant sharks, which are not dangerous to humans and feed mainly on plankton.
But not only the size of the carcharodon terrifies all living things, because such a predatory fish is firmly entrenched in the minds of people as a merciless killer, ready to attack at any opportunity. So it is: these giant predatory fish are known for attacking water sports enthusiasts(divers, surfers, swimmers).
And according to statistics, the chances of escaping from such a predator are much less than when falling under the wheels of a truck: if the carcharodon began to pursue and attack its prey, then it does not stop until it finally tastes human flesh.
Interestingly, the great white shark is on the verge of extinction, and there are only about 3500 individuals. As mentioned earlier, this predator belongs to the herring family, this also includes a number of sharks:
- ordinary mako;
- longfin mako;
- Pacific salmon;
- Atlantic herring.
Carcharodon is believed to be one of ancient organisms on the planet, and this opinion was given impetus by the research of scientists who came to the conclusion: the white shark is a close relative of the megalodon, which became extinct 5.5 million years ago. However, at the same time, other scientists believe that the carcharodon is still closer to the mako shark than to the ancient megalodon.
Range of great white sharks
The great white shark can be found in all waters of the world's oceans, where the temperature is not lower than 12 degrees and not higher than 24 degrees. In more cold water these predators are extremely rare. It is also interesting that such a fish lives both in salt water and in low-salt and desalinated water.
An interesting fact: such a predator does not and could not live in the Black Sea. This is due to the fact that the water here is too fresh, besides, there is not enough food in the Black Sea for the survival of this predatory fish.
Carcharodon can be found on the coast USA, Canada, Guadeloupe, Argentina, Chile, Japan, China, Australia, New Zealand, South Africa, as well as off the coast of Croatia and Italy, Portugal and North Africa. By the way, in New Zealand this species is protected.
largest population lives off Dyer Island that in South Africa. There are also Scientific research these predatory fish.
White sharks settle in the waters of the seas. They feed on fur seals, whales, and large bony fish. And only a large killer whale is capable of terrifying this predator.
Like most other sharks, Carcharodon has a fusiform, streamlined body, a conical head, small eyes, nostrils, and a wide mouth. The teeth of this fish are very sharp. They have a triangular shape, on the sides they have small notches.
The approximate number of teeth varies from 280 to 300 pieces; with their help, the predator easily deals with prey. All Carcharodon Teeth arranged in 5 rows. The change of the first row of teeth occurs in young individuals once every three months, and in adults - once every eight months.
The white shark also has gills, which are located on the sides of the head (5 gill slits on each side). The color is typical for all such fish: belly white, back gray. Thanks to such a transition from one color to another, this predator can easily hunt in the water column and at the same time remain invisible.
On the back of the carcharodon is one fin, two on the chest. The tail has a fin with two lobes of the same size. Carcharodons have a very developed circulatory system, which warms up the muscles and allows the predator to swim quickly.
It is interesting that this fish no swim bladder, because of which she has to be on the move all the time, otherwise she will simply start to sink. But, obviously, such anatomy does not in the least prevent her from living in the depths of the seas and oceans for millions of years.
Dimensions: how much does a white shark weigh and what is its length
For many years, ichthyologists have been researching and arguing about the size of this formidable predator and how much such a fish weighs. One of the largest white sharks was recognized as caught back in late XIX century in Australian waters, which had a length of almost 11 meters.
Another larger specimen was caught off the coast of Canada in the first half of the 20th century. Him length was 11.3 meters.
If we talk about the average size of carcharodon, then they are as follows:
- medium shark - from 4 to 5.2 meters in length and 700-1000 kg in weight;
- big shark - from 6 to 8 meters in length and 3500 kg in weight.
As a rule, females are larger than males. A big shark can be called one whose size is from 6 meters to 7.5 meters. The largest white shark can reach 12 meters in length.
And yet scientific disputes do not stop to this day. Ichthyologists question the facts about the capture of the largest carcharodons, since the difference in size between them and other white sharks is too great.
Scientists believe that the record figures are more likely not related to carcharodons, but to giant sharks, thus, which feed on plankton. Moreover, the fact of catching the largest shark off the coast of Australia and Canada was recorded not by scientists, but by ordinary fishermen.
To date, the largest size of carcharodon is considered length 6.4 m and weight 3270 kg.
What does Carcharodon eat?
Juveniles feed on small bony fish, small marine animals and mammals.
More mature individuals hunting fur seals, sea lions, shellfish, big fish, even other sharks and whales.
Due to their coloration, these predators can easily camouflage themselves while hunting, and their high body temperature allows them to move quickly and catch up with your prey. And also, thanks to active movements, active brain activity occurs, thanks to which this predator is able to come up with ingenious strategies during the hunt.
By the way, about attacks on people: very often surfers and swimmers remind carcharodons of the same sea seals with their body movements, so she can actively attack them.
But here it is worth taking into account the fact that these predatory fish prefer fatty foods. Therefore, after biting a person and tasting it, the shark swims away in disappointment. So the opinion that such predators feed on human flesh is very erroneous.
This ocean predator is one of the largest and most aggressive fish. The color of the back and sides of the great white shark can be black, brown or gray, but the belly is always white, which is the reason for its name.
The average length of these marine inhabitants is about 5-6 meters, while the weight can reach from 600 to 3200 kilograms.
But there are also real giants: for example, once it was possible to fix a white shark, the length of which was 11 meters, and according to scientists, this is far from the limit. Those individuals whose length is less than four meters are considered adolescents and have not yet entered sexual maturity.
Scientists have established interesting fact: great white sharks existed in the Tertiary period, and their length in those days reached thirty meters. The mouth of this monster was so huge that if this species had survived to the present day, eight people could easily fit in it. But such a neighborhood could hardly promise a person something good.
big shark- a real fossil animal. The great white shark is by nature a loner. It lives in almost all corners of the world's oceans, both in open waters and in coastal ones. Usually the white shark prefers the upper water layers, but if necessary, it can descend to the depth without feeling any discomfort. There was a case when this predator was caught at a kilometer depth. These Marine life prefer warm waters, but also swim in temperate latitudes. The female, after the birth of the cubs, leaves no more than two alive, she simply eats the rest.
The white shark has huge teeth that are triangular in shape and reach five centimeters. And their edges are notched. The jaws of this fish are so powerful that it can easily bite through the bones and cartilage of its prey, so there are practically no chances of salvation for those who have caught this predator “on the tooth”. It is noteworthy that the teeth of the great white shark are arranged in several rows, so if the teeth of the front row are damaged, teeth from the back rows are put forward in their place.
It takes only a few seconds for a great white shark to swallow a prey it encounters. She can not be called some kind of special gourmet, she eats almost everything, including even representatives of her own species. In the captured white sharks, the bodies of the victims, almost intact, were found in the stomachs, the length of which reached two meters. If the potential prey is larger than this size, then the shark tears it into pieces, and then eats it. This fish does not refuse even smaller food. Their prey can be sea bass, mackerel, tuna, seals, sea otters,. She does not disdain garbage, and even carrion.
This type of shark is the most dangerous to humans. They are very often
The storm of the seas, white death, a ruthless killer - as soon as they did not call this powerful and ancient creature that survived the dinosaurs. His name is great white shark. A more perfect organism in nature simply does not exist.
Description and features of the great white shark
Great White Shark (Carcharodon)- one of the largest predators on the planet. She rightfully deserved her bad reputation as a man-eating shark: there are a great many recorded cases of attacks on people.
The language does not dare to call it a fish, but it really is: the white shark belongs to the class of cartilaginous fish. The term "shark" comes from the language of the Vikings, the word "hakall" they called absolutely any fish.
Nature has generously endowed the white shark: its appearance has not changed over the millions of years that it lives on the planet. The size of the mega-fish surpasses even those that sometimes reach 10 m. Great white shark length, according to ichthyologists, can exceed 12 meters.
However, there are only scientific hypotheses about the existence of such giants, the biggest white shark, caught in 1945, was 6.4 m long and weighed about 3 tons. Maybe, the biggest in the world of unprecedented size, has never been caught, and cuts through the expanses of water at a depth not accessible to humans.
At the end of the Tertiary period, and relatively recently by the standards of the Earth, the ancestors of the white shark, the megalodon, lived in the vast depths of the ocean. These monsters reached a length of 30 m (the height of a 10-story building), and 8 adult men could comfortably fit in their mouths.
Today, the great white shark is the only surviving species of its numerous genus. Others died out along with dinosaurs, mammoths and other ancient animals.
The upper part of the body of this unsurpassed predator is painted in a grayish-brown range, and the saturation can be different: from whitish to almost black.
The length of the great white shark can exceed 6 meters
It depends on the habitat. The belly is white, because of it the shark got its name. The line between a gray back and a white belly cannot be called smooth and smooth. It is more broken or torn.
This coloring perfectly masks in the water column: from the side view, its outlines become smooth and almost invisible, when viewed from above, the darker back blends with the shadows and the bottom landscape.
The skeleton of a great white shark does not have bone tissue, but is entirely made up of cartilage. The streamlined body with a cone-shaped head is covered with reliable and dense scales, similar in structure and hardness to shark teeth.
These scales are often referred to as "skin denticles". In some cases, the shark shell cannot be pierced even with a knife, and if you stroke it against the grain, deep cuts will remain.
The body shape of the white shark is ideal for swimming and chasing prey. A special fatty secret secreted by the skin also helps to minimize resistance. It can reach speeds of up to 40 km / h, and this is not in the air, but in the salt water column!
Her movements are graceful and majestic, as if she is sliding through the water, making absolutely no effort. This hulk can easily make 3-meter jumps over the surface of the water, the sight must be said to be fascinating.
The great white shark does not have an air bladder to keep it afloat, and to keep from sinking, it must constantly work with its fins.
Good buoyancy is helped by the huge size of the liver and the low density of cartilage. The blood pressure of the predator is weak and in order to stimulate blood flow, she also has to constantly move, thereby helping the heart muscle.
Looking at great white shark photo, with its mouth wide open, you feel awe and horror, and goosebumps run down your skin. And this is not surprising, because it is difficult to imagine a more perfect tool for killing.
Teeth arranged in 3-5 rows, and white shark they are constantly updated. In place of a broken or fallen tooth, a new one immediately grows from the reserve row. The average number of teeth in the oral cavity is about 300, the length is over 5 cm.
The structure of the teeth is also thought out, like everything else. They have a pointed shape and notches, making it easy to pull out huge chunks meat from his unfortunate victim.
Shark teeth are practically devoid of roots and fall out quite easily. No, this is not a mistake of nature, rather the opposite: a tooth stuck in the body of the victim makes it impossible for the predator to open its mouth to ventilate the gill apparatus, the fish simply runs the risk of suffocating.
In this situation, it is better to lose a tooth than a life. By the way, during his life a great white shark replaces about 30 thousand teeth. Interestingly, the jaw of a white shark, squeezing prey, exerts pressure on it up to 2 tons per cm².
The great white shark has about 300 teeth in its mouth.
Lifestyle and habitat of the great white shark
White sharks are mostly solitary. They are territorial, however, show respect for larger brothers, allowing them to hunt in their waters. The social behavior of y is a rather complex and poorly studied issue.
Sometimes they are loyal to the fact that others share their meal, sometimes - on the contrary. In the second option, they show their displeasure by baring their mouths, but they rarely physically punish the intruder.
The great white shark is found in the shelf zone near the coasts of almost all over the world, excluding the northern regions. This species is thermophilic: optimum temperature water for them 12-24 ° C. An important factor is the concentration of salt, since in the Black Sea it is not sufficient and these are not found in it.
Great white shark dwells off the coast, Mexico, California, New Zealand. Large populations are observed near Mauritius, Kenya, Seychelles, Guadeloupe. These predators are prone to seasonal migrations and can cover distances of thousands of kilometers.
Great white shark food
The great white shark is a cold-blooded, prudent predator. She attacks sea lions, marine,. In addition to large animals, sharks feed on tuna and quite often on carrion.
The great white shark does not hesitate to hunt other, smaller species of its own kind, as well as. On the latter, they ambush and attack from behind, depriving the victim of the ability to use echolocation.
Nature has made the shark an ideal killer: its eyesight is 10 times better than a human's, the inner ear picks up low frequencies and infra-range sounds.
The sense of smell of a predator is unique: a shark is able to smell blood in an impurity of 1:1,000,000, which corresponds to 1 teaspoon per large swimming pool. The attack of the white shark is lightning fast: less than a second passes from the moment the mouth opens to the final closing of the jaws.
Having sunk its razor-like teeth into the body of the victim, the shark shakes its head, tearing off large pieces of flesh. At one time, she can swallow up to 13 kg of meat. The jaws of the bloodthirsty predator are so strong that they easily bite large bones, and even the entire prey in half.
The shark's stomach is large and elastic, it can hold a huge amount of food. It happens that of hydrochloric acid is not enough for digestion, then the fish turns it inside out, getting rid of the excess. Surprisingly, the walls of the stomach are not injured by the sharp triangular teeth of this mighty creature.
Great white shark attacks per person do happen, mainly divers and surfers suffer from this. Humans are not part of their diet, rather a predator attacks by mistake, mistaking a surfboard for sea elephant or a seal.
Another explanation for such aggression is the invasion of personal space, the territory where she is used to hunting. Interestingly, she rarely eats human flesh, more often spitting it out, realizing that she was mistaken.
Dimensions and the characteristics of the body do not give the victims great white shark no chance of salvation. In fact, among the ocean depths, she does not have worthy competition.
Reproduction and lifespan
Individuals less than 4 m in length, most likely immature adolescents. Shark females are able to become pregnant no earlier than at 12-14 years old. Males mature a little earlier - at 10. Great white sharks reproduce by ovoviviparity.
This method is inherent exclusively in cartilaginous fish species. Pregnancy lasts about 11 months, then several cubs hatch in the mother's womb. The strongest eat the weak while still inside.
2-3 completely independent sharks are born into the world. According to statistics, 2/3 of them do not live up to a year, becoming a victim of adult fish and even their own mother.
Due to long pregnancy, low productivity and late maturation, the number of white sharks is steadily declining. No more than 4,500 individuals live in the world's oceans.
