sharks

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Sharks (lat. Selachimorpha) is a superorder of cartilaginous fish comprising eight teams, twenty families and about 350 species. Members of the superorder widely distributed in all seas and oceans, there are also freshwater sharks. Most species belong to the so-called real predators, some species, particularly whale, and giant deep-sea sharks, eat plankton.

For many millions of years before the planet appeared the first man, ruler of the prehistoric seas was a shark. The power of evolution sowed on Earth, countless forms of life that could not stand the severe tests and disappeared one after another, as the shark continued to exist. One prehistoric era is succeeded by another, have any amphibians, reptiles, birds, and mammals – the shark continued to exist. Pterodactyls – the winged reptile for millions of years plied the skies, disappeared from the face of the Earth. Dinosaurs-Triceratops, Brontosaurus, allosaurus and many other “saurus”, it is important chestvovali on our planet died out, leaving no trace. As the shark continued to exist.

About 20 million years ago in the sea scoured a huge Stingray, weighing over 100 pounds, and more than 25 different species of sharks, including sharks, reaching 36 meters in length. The length of these monstrous sharks was Opredelenie their huge teeth. Some of the teeth found in California, weighing 340 grams each and reach 15 centimeters in length, and seven – and ten teeth are quite common. They are triangular in shape and closer to the teeth of modern great white sharks that do not exceed 5-6 inches now with a body length of shark of 12 meters (maximum length). These teeth belonged to the ancestor of the modern great white shark the carcharodon, in huge quantities inhabited the seas. When they were first found in the seventeenth-century scientists, naturalists believed that this fossil bird tongues or teeth of serpents. They could not imagine that this shark’s teeth, and ascribed them to the mythical animal. Continue reading

What sharks are the most dangerous?

About the brutality of the sharks is legendary. People since ancient times afraid of sharks, because sharks of any size can be dangerous. However, among all the sharks you can highlight a dozen of the most dangerous, which can end badly.

Sharks are dangerous not only because they are strong, have sharp teeth and powerful jaws. The main danger lies in the unpredictability of the behavior of toothy predators: despite the fact that the habits of sharks are being studied for a long time, to predict with accuracy how the shark in any given situation, almost impossible.

Dangerous shark species

Today there are more than 450 species of sharks of different sizes, the smallest can reach a length of 17 cm, the biggest is up to 20 meters. But the real danger to humans represent only some species of sharks. Recent years have witnessed the most attacks on humans great white, bull and tiger sharks.

Great white shark

This shark is called “great”: in length it can reach up to 7 meters and weight up to three tons. The mere sight of this blood-thirsty predator is able to inspire terror. If you watched the movie “Jaws”, then you understand what is involved. The reputation of the great white shark is the most grim: in 2012, the year its victims were 11 people, three cases ended in the death of the victims. Continue reading

The greatest myths of modern times, Sharks

The shark is a collective name. There is a white shark, blue, tiger, cat, soup, mackerel, shark-Fox, nurse shark, hammerhead shark. Scientists consider 350 species of these fish. And only 27 of them are accused of attacks on humans. And a few that occur only once.

Thanks to the joint efforts of marine biologists and divers-enthusiasts have managed to debunk some common misconceptions about sharks.

Myth: Most sharks eat people.

Fact: Of the approximately 400 species of sharks in attacks on people were seen a total of about 11. Most sharks are simply too small to pose a threat to humans. But a large white shark people are not too taste, although sometimes they mistakenly attack people, mistaking them for sea lions or seals, which are their favorite prey. Besides, they live at a depth where meeting people is unlikely. Although annually reported approximately one hundred cases of shark attacks on humans, actually elephants are being killed every year twice as many people (about 200) . Dogs kill thousands of people every year!

Myth: Sharks are stupid animals with small, primitive brain.

Fact: the sharks (as the rays) the size of the brain and body comparable to birds and mammals.The research was conducted, which demonstrated that the yellow shark learning is quicker and lasts longer than a cat or a rabbit. This, of course does not mean that sharks are as smart as birds and mammals, but still… Continue reading

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