Dolphins - amazing animals

Dolphins, dolphins (lat. Delphinidae) - a family of mammals of the order Cetacea, suborder of toothed whales (Denticete).

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Dolphins are found in many seas and oceans of the world, including in the Black Sea.
Dolphins live up to 75 years, usually about 50 in captivity usually about 30. With its 88 teeth Black Sea dolphin eats about 30 kg. fish of the day, plenty of dolphins - up to 500 kg. Body temperature dolphin - such as a person 36 and 6 degrees. The gestation period of about 12 months of dolphins. The female dolphins usually brings a cub in the 50-60 cm long, and while carefully guarding him.

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At the mention of the dolphin more likely a person imagine the kind of Bottlenose Dolphin (Tursiops truncatus). Part of its popularity bottlenose obliged to numerous references in film and literature, and a high capacity for learning.

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Dolphins - this is not a fish, and mammals - feed calves milk and do not breathe through gills and lungs. From time to time they need emerges from the water to breathe. Dive they usually no longer than 1-3 minutes, but may remain submerged for 10 minutes and, immersed to a depth of tens of meters.

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Skin dolphins - a miracle of nature, they are able to extinguish the swirling water at the surface of the floating body quickly, reducing speed - dolphins studied submarine designers, creating artificial skin for submarines. A dolphin's skin feel to the touch - quite unusual, and also - brings joy to look at it - dense, like plastic, and spend a hand - gentle and soft, it seems - the thin silk.

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When the dolphins began to study and train in the middle of the last century, the first results of this work seemed so unusual and even strange (this much talked about, written and filmed a movie) that gradually formed the legend of unusually high intelligence of dolphins; often you can hear that they are - not a stupid man, but their mind - the other.
Adult dolphin brain weighs about 1700 grams, and the person - in 1400. At the dolphin twice the convolutions in the cerebral cortex. At the same time, in a cubic millimeter of its substance it is relatively small neurons (less than in the brains of primates).

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The results of studies of the behavior and physiology of the brain of dolphins are very contradictory. Some have their ability to learn about the level of dog and show that chimpanzees to dolphins very far. Research ways to communicate dolphins, by contrast, is pushing to the conclusion that we have not yet come close to an understanding of this form of life in the wild, to compare the level of intelligence of dolphins and chimpanzees is simply incorrect. A property of the dolphin brain is quite unique: it has never, really - does not sleep. Sleep - alternately - the left, the right hemisphere of the brain. Delphine is necessary from time to time, come to the surface to breathe. At night, during which, in turn, meet the waking half of the brain.

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Language dolphins can be divided into 2 groups:

Sign language (body language) - various poses, jumps, turns, different ways of swimming, signs supplied tail, head and fins.
The language sounds (own language) - sound alarm, expressed in the form of pulses of sound and ultrasound. Examples of such sounds can be: chirping, buzzing, screeching, grinding, the clicking, smack, squeaks, pops, squeaks, roaring, yelling, screaming, quacking, whistling.

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The most expressive are the whistle that dolphins, there are 32 species. Each of them can designate a particular phrase (signals of pain, anxiety, and the rallying cry of welcome "to me" and so on. D.). Scientists studied the dolphins whistling, using the method of Zipf and got the same slope as that of the human language, that is the information carrier. Recently, about 180 dolphins found signs of communication that are trying to organize, making dictionary of communication of these mammals. However, despite numerous studies, fully decipher the language of dolphins to date have not succeeded.

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Each dolphin has its own name, to which he responds when he is addressed relatives. This conclusion was American scientists, the results of which were published in the Journal of the National Academy of Sciences (PNAS). Moreover, the experts who conducted their experiments in the US state of Florida, found that the name given to a dolphin More at birth and is a characteristic whistle.

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Scientists have caught networks on the outside 14 light gray bottlenose dolphins and a variety of recorded sounds made by these mammals in the course of their communication with each other. Then use the computer records were carved out of "names". When the name "lose" for the flock, he responded to a specific individual. "Name" is a characteristic of a dolphin whistle, the average duration of which - 0, 9 seconds

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Everyone has heard that sometimes dolphins and other whales beaching. Sometimes it is due to illness, injury or poisoning. There is another hypothesis explaining the reason for this strange behavior of the dolphins: it turns out that in some form the shore, folded certain types of deposits, among the cacophony, give rise to the surf, sometimes there is sound, exactly corresponding dolphins cry for help. Pets heard these sounds instinctively rush to help - and get to shore.

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Dolphins eat fish. A lot of fish: each member of the pack, the day is to eat 10-30 kg. Dolphins - blooded, they need to maintain a high body temperature sometimes in very cold water. This helps the subcutaneous layer of fat - it acts as a thermal insulator and ostochnik ennergii for intracellular stoves: burning fat and carbohydrates to release heat energy. Stocks of fuel necessary to fill up all the time, so they are constantly hunted. They blow up school of fish - no one in the sea does not have to swim faster, and surround it. If it occurs very close to the shore, dolphins form a semi-circle and pressed the fish to the beach; squeezing his hunting system, they push the fish on samoё shallow water and eat it there - while they swim into the best surf, so small that their dorsal fins sticking out of the water, and breast - touch the sand at the bottom.

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Surrounding the school of fish out at sea, dolphins do not rush, individually for production, and organized a flock kept in the ring, not allowing the fish to scatter and turn pierce the jamb. Catching prey back to its place in the paddock.

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Where to fish - there and dolphins. At the Black Sea coast more fish in the spring and autumn - when the shoals of mullet, anchovy go to summer feeding grounds in the Sea of ​​Azov, and returned to winter in Black - along the coast of the Caucasus. Therefore, dolphins often appear here in April-May and September-October. And in the Kerch Strait - the gate of the Azov Sea - Hundreds of dolphins are an outpost, encountering herds migrating fish.
In the summer of bottlenose dolphins also often fit directly to the beach - often they can be seen early in the morning or afternoon - perhaps because at this time is less than swimmers.

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Dolphins live in packs in which everything - family, so mutual aid they developed so well. They always help weakened dolphin stay at the surface, so that he choked; known stories about how the dolphins came to the rescue drowning people. They never behave with hostility.

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Learn tricks of the dolphins very quickly - it is enough just one exercise right on cue, for which they will encourage fish to hang entrenched in the memory. However, they are also easy to forget the skills, if the coach forgets to reinforce a useful habit.

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Definitely, something forces us to treat the dolphins in a different way than other animals - "friends of man" ... friendly, funny, cute ... They - really friendly and curious: are not afraid to swim and play with the man, but more often - or people do not pay attention, or simply swim away - they have their own concerns in the sea. Maybe it's in the smile of a dolphin? After all, they are always smiling - so, somehow, to arrange their person (even a muzzle do not want to call it!). And the smile with big eyes - one of those smiles that make us involuntarily smile back - not all people are able to smile like that.

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