Little dolphins. Dolphins are aquatic mammals

Both adults and children love dolphins. These mammals seem incredibly intelligent, and interacting with them even has a therapeutic effect! Find out ten interesting facts about them.

There are more than thirty species of dolphins

Dolphins are marine animals found throughout the world. There are more than thirty types of them. All of them are predators, feeding on fish and squid, and sometimes even seals and other marine animals. Most species inhabit the ocean. But there are also five species that live in rivers. Interestingly, most likely they did not descend from a common ancestor, but developed in parallel. Some river dolphins closer to oceanic than to other river species. Research has shown that river dolphins descended from ocean dolphins, which moved to fresh water due to competition with other species.

Dolphins can be from a meter to ten meters long

The smallest dolphin of all lives on Maui - its length is about a meter. The largest are killer whales, also known as killer whales. This name is erroneous, because these are not whales, but a type of dolphin.

Dolphin ancestors began living in water fifty-five million years ago

Nature often hides amazing facts. Researchers managed to find out the incredible - dolphins descended from land mammals that began living in the ocean about fifty million years ago. It was so long ago that other species descended from those land creatures are giraffes and hippos. The dolphin skeleton contains reduced bones that were once paws. They are present in dolphins of all species. What's interesting is that whales seem quite similar to dolphins, but they are completely different.

Killer whales are dolphins ten meters in size

Most amazing fact about dolphins is that they also include killer whales. Killer whales live all over the world from the Arctic to the Antarctic. Their features are so different from those of dolphins because their last common ancestor was eleven million years ago. Since then, killer whales have evolved in their own way, different from other species. Some scientists distinguish from three to five subspecies of these creatures, which differ in external and some other features. However, it is possible that differences are simply formed under the influence of habitat - in coastal waters, in the deep sea, or during migration between these two territories.

Dolphins from the Amazon can turn their heads ninety degrees and have a goatee.

During adaptation to underwater life, these creatures lost the fur that their ancestors had. But when dolphins are just born, they still have it around their mouth. Then she disappears - unless we are talking about Amazon dolphins. This species is distinguished by fur that remains near the mouth for life. The fur helps to better determine direction in the dark waters of the jungle, making it easier for dolphins to find their prey. In addition, this species has special neck bones - the Amazonian dolphin can turn its head ninety degrees.

Dolphins hear ten times better than humans

Dolphins have incredibly keen senses, which makes them such excellent hunters. They have excellent vision, as well as incredibly acute hearing. Using a variety of clicks and squeaks, they find their prey using echolocation. They pick up all sounds, like a perfect radar, with a special organ located in the lower jaw. This is a chamber filled with fat that connects the jaw to the inner ear. All vibrations are transmitted through the jaw to the ear.

Dolphins only eat meat

Dolphins seem to be the cutest creatures of all the inhabitants of the sea. Even killer whales seem cute to some. You can often see children's toys in the form of these predatory creatures. Don't be fooled - these are carnivores that feed exclusively on meat! They usually catch fish, but they can also eat other creatures, from squid to seals, and killer whales can even kill whales that are larger than them. There is not a single predator that could cope with the killer whale - this is the most severe inhabitant of the ocean. Even river species are exclusively predatory. Humans are not usually of interest to dolphins, but there have been cases of killer whales eating their trainers when kept in zoos.

Dolphins gather in large schools

These are very sociable animals. They are known to communicate in a variety of sounds. Each has its own whistle, by which others recognize it. They even have names! In addition, these mammals gather in large groups that not only hunt, but also simply live together. Groups of up to a thousand individuals are known.

Bottlenose dolphins teach each other how to use tools

In addition to a wide range of sounds, which some scientists compare to language, bottlenose dolphins can use tools. If we take into account the presence of both language and the ability to use objects, we can say that this species of dolphins has a culture. Bottlenose dolphins live in Indian and Pacific Oceans. They hunt fish in a special way among the sand and rocks on the ocean floor. To avoid damaging their mouths on rocks, dolphins loosen the sand with a sponge held in their teeth, thereby scaring the fish. This tactic is passed on from mother bottlenose dolphin to her cubs. Other species know how to use sticks and seaweed during mating games. Obviously, these are the most intellectually developed animals on the planet after humans.

People and dolphins fish together in the Santa Catarina Lagoon

People have been able to cooperate with these mammals since the time of the Roman Empire. Fishermen can fish with them. Here's how it happens: dolphins catch a school of fish in a net. When a fish is caught, the fishermen share part of the catch with their colleagues. This technique is still used today in Brazil, in the Santa Catarina Lagoon. U naval forces The United States of America has a training program for these creatures. They can be trained for military operations. Mammals can find mines and save people drowning in the sea. They were used to participate in war in the middle of the last century, although the exact data about this remains classified.

Scientific classification

intermediate ranks

Domain: Eukaryotes

Kingdom: Animals

Type: Chordata

Class: Mammals

Order: Cetaceans

Family: Dolphinidae

International scientific name

Pied dolphins (Cephalorhynchus)

Common dolphins (Delphinus)

Pygmy killer whales (Feresa)

Pilot whales (Globicephala)

Gray dolphins (Grampus)

Malaysian dolphins (Lagenodelphis)

Short-headed dolphins (Lagenorhynchus)

Whale dolphins (Lissodelphis)

Irrawaddy dolphins (Orcaella)

Killer whales (Orcinus)

Beakless dolphins (Peponocephala)

Lesser killer whales (Pseudorca)

Long-beaked dolphins (Sotalia)

Humpback dolphins (Sousa)

Dolphins (Stenella)

Large-toothed dolphins (Steno)

Bottlenose dolphins (Tursiops)

Dolphins, or dolphins (lat. Delphinidae) are a family of mammals of the order Cetaceans, suborder of toothed whales (Odontoceti).



general description

Skeleton (bottom) and model (top) of a dolphin

Dolphins are characterized by the presence in both jaws of a fairly significant number of uniform conical teeth, both nasal openings are usually connected into one transverse crescent-shaped opening at the top of the skull, the head is relatively small, often with a pointed muzzle, the body is elongated, and there is a dorsal fin.

Very mobile and dexterous, voracious predators, living mostly socially, are found in all seas, even rise high into rivers, feeding mainly on fish, mollusks, and crustaceans; sometimes they attack their relatives. They are also distinguished by their curiosity and traditionally good attitude towards people.

Some dolphins have a mouth extended forward in the form of a beak; in others the head is rounded in front, without a beak-like mouth.

Dolphins swim extremely fast, schools of dolphins often follow ships, using, in addition to the “Grey's paradox” described below, the wake of ships for even greater acceleration. The dolphin has been loved and popular since ancient times: there are many poetic legends and beliefs (the legend of Arion) about dolphins and their sculptural images.

The word dolphin goes back to the Greek δελφίς (delphis), which in turn came from the Indo-European root *gʷelbh - “womb”, “womb”, “womb”. The animal's name can be interpreted as "newborn baby" (perhaps due to its resemblance to a baby or because the dolphin's cry is similar to that of a child).



Physiology

The gestation period of dolphins is 10-18 months. The female dolphin usually brings one calf 50-60 cm long and carefully guards it for some time. Dolphins apparently grow slowly, and their life expectancy should be quite significant (20-30 years). In some cases, scientists have observed that the cubs do not sleep at all for the first month of life, forcing the females to be active during this entire time. In the 1970s, a group of scientists from the Utrish sea station IPEE discovered an unusual sleep pattern in dolphins. Unlike other mammals studied at that time, only one of the two hemispheres of the brain is alternately in a state of slow-wave sleep. Perhaps the main reason for this is that dolphins are forced to rise to the surface of the water from time to time to breathe.



Brain Development

Dolphins' brains, in proportion to their body size, are much larger than those of our closest relatives, chimpanzees, and their behavior indicates a high degree of mental development. The brain of an adult dolphin weighs about 1,700 grams, while that of a human is 1,400. A dolphin has twice as many convolutions in the cerebral cortex as a human.

According to the latest scientific data from cognitive ethology and zoopsychology, dolphins not only have a “vocabulary” of up to 14,000 sound signals, which allows them to communicate with each other, but also have self-awareness, “social cognition” and emotional empathy, a willingness to help newborns and the sick , pushing them to the surface of the water.

Movement

Associated with dolphins is the so-called. "Gray's Paradox". In the 1930s Englishman James Gray was surprised by the unusually high swimming speed of dolphins (37 km/h according to his measurements). Having made the necessary calculations, Gray showed that according to the laws of hydrodynamics for bodies with constant surface properties, dolphins should have had several times greater muscle strength than was observed in them.

Accordingly, he suggested that dolphins are able to control the streamlining of their bodies, maintaining a laminar flow around them at speeds for which it should already become turbulent. In the USA and Great Britain after World War II and 10 years later in the USSR, attempts began to prove or disprove this assumption. In the USA, they practically stopped in the period from 1965-1966 to 1983, since, based on incorrect estimates, erroneous conclusions were made that the “Gray's paradox” does not exist, and dolphins only need muscular energy to develop such speed. In the USSR, attempts continued in 1971-1973. The first experimental confirmation of Gray's guess appeared.

Signals

Dolphins have a sound signaling system. Signals of two types: echolocation (sonar), which serve animals to explore the situation, detect obstacles, prey, and “chirps” or “whistles”, for communication with relatives, also expressing the emotional state of the dolphin.

Since 1942, researchers have learned that dolphins and toothed whales emit ultrasonic echolocation clicks, which they use to navigate muddy water. Working with the Hawaiian spinner dolphin (Stenella longirostris), whale researcher Professor Ken Norris found that by directing ultrasonic signals at schools of fish, whales can stun and sometimes even kill fish. These signals cause the fish's air-filled swim bladders to resonate so intensely that the vibration transmitted to body tissue disorients the fish. No less interesting was the discovery that dolphins can use not only very high, but also low-frequency sounds to stun prey. In 2000, Dr Vincent Janik studied the common bottlenose dolphin (Tursiops truncatus) in the Moray Firth, Elginshire. He found that bottlenose dolphins produce a characteristic sharp noise of low-frequency sounds exclusively when eating. Since dolphins themselves are insensitive to low frequencies, Zhanik suggests that dolphins produce these sound signals to stun their prey.

The signals are emitted at very high, ultrasonic frequencies that are inaccessible to human hearing. The sound perception of people is in the frequency band up to 20 kHz, dolphins use a frequency of up to 200 kHz.

Scientists have already counted 186 different “whistles” in the “speech” of dolphins. They have approximately the same levels of organization of sounds as a person: six, that is, sound, syllable, word, phrase, paragraph, context, they have their own dialects.

In 2006, a team of British researchers from the University of St. Andrews conducted a series of experiments, the results of which suggest that dolphins are capable of assigning and recognizing names.

Currently, a number of scientists are working on deciphering complex signals using the CymaScope device, designed for this purpose by the British acoustic engineer John Stuart Reid.

Dolphins are used in pet therapy to treat people using ultrasound sonar.

Representatives



Common dolphin

The common dolphin (Delphinus delphis L.) has from 100 to 200 (their number varies) small, conical, slightly curved teeth, separated by equal intervals; the snout is of moderate length separated by a groove from the slightly convex forehead. The upper side of the body and fins are grayish or greenish-black; the belly is white; the skin is very smooth and shiny. Reaches 2 m in length; dorsal fin height 80 cm; pectoral fins 15-18 cm wide, 55-60 cm long. Found in all seas northern hemisphere, both off the coast and in the open sea; also enters rivers. They live in flocks of 10, 100 or more (up to several thousand) animals.

D This species of dolphins is quite common and often seen. Typically, representatives of the genus form flocks and move together. They can be seen near the shore, or accompanying ships. The size of an adult individual is about 2 m, weight is about 80 kg.

The common dolphin prefers fish as food, but if necessary, it can also feed on other marine life. When choosing fish, he will give preference to anchovy, but will not disdain octopus in difficult times.

The animal is very mobile, it can jump, as if flying out of the water, and such a flight is carried out at a distance of about 10 m. It is often on the surface, and spends less time under water in total. But there are also deep-sea representatives who hunt and live at depth, occasionally rising to the upper layers of water.

Dolphins of this species usually live in births - for example, cohabitation of several generations is often found. During the mating season, it is possible to divide into flocks based on gender. Females “in position” or young mothers may separate. Animals help each other - no matter how strange it sounds, and this makes them even more like people.

The average lifespan of dolphins is 30-35 years - this species is no different from the others. The speech of the common dolphin is varied, there are loud and strong sounds, usually the animals “whistle.” These individuals can be found in the oceans and seas almost everywhere - the population is very widespread. Reproduction of animals occurs in the warm months; the cub is born for about a year.

Appearance - body size about 2 m, elongated muzzle and dark color. A distinctive feature is the light sides and belly. The eyes and fins are highlighted. The back is dark, in the form of a “blanket”. The oral cavity contains sharp teeth, of which dolphins have about 200.

bottlenose dolphins

Bottlenose dolphins (Tursiops truncatus) are the most famous and popular species of dolphin. When you mention a dolphin, a person is more likely to imagine this particular species. Bottlenose dolphins owe their popularity partly to numerous references in cinema and fiction and their high ability to learn.

Distributed throughout the world. Representatives of the genus of bottlenose dolphins living in the northern part Atlantic Ocean(occasionally enter the Baltic Sea), are less common than the previous species and reach a larger size (3.5-4.5 m in length); The Greenlanders called it “nezarnak”.

This type dolphins - exactly the one that is well known to all of us from films, videos, etc., and each of us, probably, could see it when we were at sea. The population is very common, usually in groups of 5-10 animals. Flocks of more than 400 animals are possible - but this can only be seen at sea.

Adults measure more than 2 m in size and weigh approximately 200-300 kg. They usually choose fish as food, sometimes octopuses are used. This type of dolphin has been well studied by scientists. The animal can live either alone or in groups. It is often located near the shore, but searches for food at the bottom. The bottlenose dolphin is active during the daytime, and at night it sleeps. To sleep, the dolphin is placed on the surface of the water; it can also rest during the day, after a hearty lunch.

The animal's speech has been well studied - today certain signals can be identified, for example, when a bottlenose dolphin wants to eat, it makes sounds similar to the meowing of a cat. If she is hunting, the sound is similar to the barking of a dog; to scare away the animal cracks or clicks. There are other sounds that allow animals to communicate quite freely.

The animal can be found in almost all ocean waters, preferring warmer ones. The bottlenose dolphin breeds in the warm season and bears its young for 1 year. A pregnant female avoids other dolphins and becomes less active. The baby appears underwater and immediately rises to the surface. The female finishes feeding after about 2 years.

The appearance of a dolphin is familiar to everyone - a dark color with a light belly, a large dorsal fin, an elongated muzzle, and clear outlines. Variations in color are possible, but small. The animal has a friendly character, is highly trainable, and quickly remembers commands.

  • Tropical dolphin (D. tropicalis)

    • Genus Prodolphins (Stenella)

    • Striped dolphin (S. caeruleoalbus)
    • Malayan dolphin (S. dubia)
    • Spotted dolphin (S. pernettyi)
    • Bridle dolphin (S. frontalis)
    • Spinning dolphin (S. longirostris)

    Genus Long-beaked dolphins (Sotalia)

    • Amazonian dolphin (S. fluviatilis)
    • Chinese white dolphin (S. chinensis)
    • Sunda white dolphin (S. borneensis)
    • West African dolphin (S. teuszi)
    • Guiana dolphin (S. guianensis)
    • Lead dolphin (S. plumbea)
    • Speckled dolphin (S. lentiginosus)

    Genus Large-toothed dolphins (Steno)

    • Wrinkled-toothed dolphin (S. bredanensis)

    Genus Cetacean dolphins (Lissodelphis)

    • Northern right whale dolphin (L. borealis)
    • Southern right whale dolphin (L. peroni)

    Genus Short-headed dolphins (Lagenorhynchus)

    • White-sided dolphin (L. acutus)
    • White-faced dolphin (L. albirostris)
    • Crossed dolphin (L. criciger)
    • Short-headed dolphin (L. obliquidens)
    • Dusky dolphin (L. obscurus)
    • Southern dolphin (L.australis)

    Genus Beakless dolphins (Peponocephala)

    • Beakless dolphin (P. electra)

    Genus Malaysian dolphins (Lagenodelphis)

    • Sarawak dolphin (L. hosei) Commerson's dolphin (C. commersoni)

  • Heaviside's dolphin (C. heavisidei)
  • Hector's dolphin (C. hectori)
  • Chilean dolphin (C. eutropia)

    • In total, the dolphin family includes about 40 species. Of these, 11 species are found in Russian waters. Porpoises are often classified as dolphins.

    Dolphins are also called species belonging to the superfamily river dolphins.

    Security

    Some species and subspecies of dolphins are on the verge of extinction and are protected by local and international legislation. One example is the New Zealand subspecies of Hector's dolphin known as the Maui dolphin (Cephalorhynchus hectori maui). Total in waters North Island New Zealand is home to fewer than 150 of these dolphins.

    Since 1966, after the adoption of the CITES Convention (Appendix 2), dolphin fishing was prohibited in the USSR. Türkiye has not yet ratified this treaty.

    2007 was declared by the UN as the “Year of the Dolphin” and, due to its success, was extended to 2008.

    Dolphin therapy

    Dolphin therapy is a method of psychotherapy that is based on communication between a person and a dolphin. It is carried out in the form of communication, games and simple joint exercises under the supervision of a specialist. It is often used in the treatment of diseases in children such as cerebral palsy, early childhood autism, attention deficit hyperactivity disorder, etc.

    Fighting dolphins

    Fighting dolphins are dolphins trained for military purposes. United States and Russian security agencies have trained oceanic dolphins for several tasks.

    Their training included detecting underwater mines, rescuing sailors after their ship was destroyed, locating enemy combatants, and searching for and destroying submarines using kamikaze techniques.

    There were even suggestions about the possibility of installing complex equipment, for example, sonar jamming devices, search devices, and so on. The US Navy denies ever training marine mammals cause damage or harm to people, and also deliver weapons to destroy enemy ships.



    Captivity

    A dolphinarium is a special aquarium for demonstrating trained dolphins to spectators. As a rule, large aquariums show killer whales and bottlenose dolphins, as well as performances with their participation.

    Dolphins have long been one of the most beloved waterfowl for humans. And this is not surprising! After all, dolphins are the most peaceful, intelligent and friendly creatures on the planet! When we talk about dolphins, we always imagine trained cetacean creatures performing acrobatic tricks. However, there are countries that are categorically against dolphinariums, believing that these smart creatures should not live outside the natural environment, because the number of dolphins is already significantly decreasing from year to year. And only the human factor is to blame for this.

    A little history

    It is assumed that the sperm whale, whale, dolphin, including the porpoise descended from the same ancestors - mammals that inhabited the earth millions of years ago, but were not strictly land animals, but rather loved to hunt and live in the water. These are mesonychids - omnivorous creatures with hooves like those of horses and cows, with a predatory, wolf-like appearance. According to approximate data, mesonychids lived for more than sixty million years, and they inhabited the modern continent of Asia, part Mediterranean Sea(in ancient times it was the Tethys Sea). These animals most likely ate any small aquatic animals and any fish that then inhabited the numerous swamps off the coast.

    And due to the fact that mesonychids most spent their lives in any body of water, their appearance gradually began to develop in breadth, streamlined, their limbs turned into fins, while the hair on the skin began to disappear, and under it, thick subcutaneous fat developed and intensified. To make it easier for animals to breathe, the nostrils ceased to fulfill their original function: in the process of evolution, they became a vital organ for the animal, since creatures could breathe through them, and all thanks to their displacement to the top of the head.

    Even if it was believed for a long time that the ancestors of cetaceans, including dolphins, were indeed mesonychids, they still “borrowed” most of all from hippopotamuses, and this is proven by numerous molecular studies. Dolphins are not just descendants of these artiodactyls, they are also deeply similar and part of their group. Until now, hippos and hippos live mainly in water; they only spend a couple of hours on land to eat. That is why scientists suggest that hippos are one of the evolutionary branches of cetaceans. It’s just that whales went further than hippos, they completely abandoned life on land and completely switched to life in the water.

    And if the relationship between hippopotamuses with hooves and legless cetaceans seems strange to you, then we would like to give another version of the taxonomy, for example, land animals with 4 legs that evolved from fish. It’s just that we shouldn’t be surprised that long before our civilization appeared, the evolution of dolphins proceeded so rapidly.


    Description of dolphins

    Dolphins are large waterfowl that breathe air, unlike fish, whose breathing function is provided by gills. Sea dolphins are in the water all 24 hours, and this is where they give birth to little dolphins. Since the female feeds her babies herself, they are therefore warm-blooded creatures, mammals.

    Unlike their relatives, whales, dolphins are more beautiful creatures. Apart from sharp teeth, no sinister intrigues can be found in their intelligent and friendly gaze. So, an adult dolphin can be 2.5 meters long and weigh only three hundred kilograms. Whereas it can be nine meters long and weigh eight tons. Males are always larger than females, by at least 20 centimeters. They have more than eighty teeth. The color of the body and fins is black or gray, while the belly is white.

    The largest body cetacean dolphins have a brain that is amazingly awake all the time while the dolphin is sleeping. The brain allows the animal to breathe all the time, even when it is sleeping: this way the dolphin will not drown, because the supply of oxygen for cetaceans is very important for life.

    Scientists have called dolphin skin a natural miracle. This is their wealth! When dolphins calmly dampen the water turbulence, when the body needs to slow down a little.

    This is interesting!
    The creators of submarines have long looked closely at how dolphins swim. Thanks to the dolphins, the designers were able to create an artificial skin for the submarine.


    Dolphins: what they eat and how they hunt

    Shellfish, various types of fish and other aquatic animals are the food of the dolphin. Interestingly, dolphins can eat a lot of fish in a day. Dolphins hunt fish in schools, and each member of the school can eat up to thirty kilograms. All this is due to the fact that dolphins are animals that, when too low temperature conditions Ocean or sea water (below zero degrees Celsius) must always maintain its own temperature so that it is optimal. And warm-blooded dolphins are helped in this by thick subcutaneous fat, which is constantly replenished due to huge amount food. That is why dolphins are always on the move, hunting, and only at night allow themselves to rest a little.

    A school of dolphins can very quickly catch up with a school of fish, because in the sea these animals are aces. If the dolphins are already close to the beach, they instantly form half rings around the fish in order to push their future food to the shallow water and eat there. As soon as dolphins capture schools of fish, they do not immediately rush at them, but then continue to keep them in a circle so that they do not swim away, and each member of the pod can have lunch or dinner with their favorite food.

    To see dolphins, just look for a school of fish. These cetaceans will definitely live where there are a lot of fish. In summer, dolphins can be found in abundance in Azov, when mullet and anchovy move to the sea to feed. Dolphins also swim close to the Caucasian shores in early autumn, when fish begin to migrate in herds.

    As you may have noticed, it is rare to see one dolphin in the ocean, since these animals are very friendly, love to live in schools, hunt together, and even dolphins can jump beautifully and perform their tricks together with their comrades. Be that as it may, dolphins never got along with killer whales. There are also still poachers who hunt these friendly earthly creatures. Despite everything, dolphins trust people and even know how to communicate not only with each other, but also with other animals. They will never leave their comrades in trouble. And in case of severe danger, they can even help a person. There are so many legends and stories in the world about dolphins saving people’s lives. Some even watched as dolphins pushed boats that were carried away by the winds to the shores.


    Dolphin breeding

    Unlike other inhabitants water world, dolphins are the only ones that are born with tails, not heads. And that's true. Loving mothers do not leave their babies even two or three years after birth.

    This is interesting!
    Dolphins are incredibly sensual and compassionate animals. A little dolphin, even after it becomes a completely independent adult male or female, never, under any circumstances, leaves its parents.

    And not only do dolphins experience great affection and love for their own fellow creatures, but even for whales, other animals (they don’t like killer whales) and for people. Once a female and male have babies, they never leave each other, even after having numerous babies. Who else but dolphins know how to love their young, tenderly and lovingly treat them, teach them, take them hunting, so that soon the children themselves know how to hunt fish.

    This is interesting!
    If dolphins are hunting and sense danger, they lead their babies behind, but if there are no external threats, the baby dolphins calmly swim in front of their parents. Interestingly, after the cubs the females swim, and then the males - the protectors.

    Relationships with people

    Since each dolphin lives in peace and harmony with its fellow tribesmen and whales, it behaves accordingly. The sense of help in these animals is particularly developed. They will never leave a sick dolphin to die; they will even save a choking person at sea if, by a lucky chance, they find themselves nearby. Dolphins can hear a person’s cry for help far away, since their hearing is very developed, as is their brain.

    The fact is that dolphins spend all their time in the water, which is why their vision is weakened (weak water transparency). Then, the hearing is perfectly developed. The dolphin uses an active location - the hearing is able to analyze the echo that occurs when it produces characteristic sounds from any objects surrounding the animal. Based on this, the echo tells the dolphin what shape and length the objects around him are, what they are made of, and in general, what they are. As you can see, hearing fully helps fulfill the visual role for the dolphin, which does not prevent this peace-loving creature from feeling complete in such a complex world.

    It's easy for a person to tame a dolphin. Fortunately, like a dog, the animal is easy and simple to train. All you have to do is entice the dolphin with a delicious fish. He will perform any somersault for the public. Although dolphins have one flaw, they can forget any trick very quickly if a person forgets to feed them on time.

    Why do we all treat dolphins differently than other animals? Looking at these cute and funny creatures, you forget about how huge these animals are, and how, despite their size, they are the only cetaceans that can safely be classified as the best “friends”.

    Dolphins are like grandmothers on a bench, overly curious. They swim up to a person with interest, flirt with him, throw a ball, and even smile, although few people notice this. They are designed to smile at us, laugh with us. Well, we can’t call a dolphin’s face a muzzle, the smile on their face is cheerful and friendly – ​​that’s what attracts us to them!

    Dolphins love us, we love them. But there are... heartless people who, for the sake of profit, forget about humanity and kill these peaceful creatures. In Japan, dolphin hunting is amazing! They don't even think about talking about sympathy for dolphins. On other continents, dolphins are placed in dolphinariums for the amusement of people. In cramped conditions in which they do not live longer than five years (for comparison, in nature, dolphins live up to fifty years).

    This is interesting!
    The Indian state has become the fourth state in the world to ban the construction of dolphinariums. The first countries to ban keeping these cetaceans in captivity were Asian Chile, Costa Rica, and Hungary. For Indians, dolphins are the same as a person who also has the right to freedom and life in nature.


    Dolphin therapy

    A story of great friendship sea ​​dolphins and man goes far into the past, even before scientists began to call these animals dolphins. Researchers of the body language of cetaceans have come to the conclusion that they have developed verbal communication abilities in the same way as humans. If a mentally ill child, an autist, spends a lot of time with dolphins and “communicates” with them, then this will have a beneficial effect on him. The child begins to smile and laugh. The British talked about this back in the 70s of the last century. Subsequently, dolphin therapy began to be actively used to treat not only mental and neurological diseases, but also many physical ones. Swimming with dolphins is beneficial; you can relieve stress, severe headaches, neuralgia and even rheumatism.

    Abnormalities in behavior

    All of you have probably seen this picture on the news or on the Internet, when the beaches are full of dolphins that have stranded themselves. Often they are thrown out on their own because they are very sick, injured, or poisoned. Dolphins clearly hear sounds from the shore, which are very similar to cries for help from their fellows. Therefore, upon hearing such a cry, dolphins rush to the shore to help, and often find themselves trapped.

    Probably, many at one time wondered: is a dolphin a fish or a mammal? After all, like many representatives of fish, it lives in the oceans and seas and leads a lifestyle similar to them. However, dolphins are aquatic mammals that belong to the class of cetaceans.

    Relatives of this animal are whales and killer whales. More ancient, on this moment The already extinct ancestors are considered to be predators - sea otters, which, like dolphins, lived in the water.

    Main features of a mammal

    This animal species is diverse, extensive and there are about 50 different species. Dolphins are ancient mammals that arouse genuine interest among people. They are called intelligent and understanding beings.

    The appearance of the dolphins is several unusual for sea ​​creature . There are no scales on its body, like those of fish; on the contrary, its cover is streamlined and slippery, so the animal is well adapted to both the depths and the surface of water.

    Description and characteristic features of dolphins:

    Skin and color of a mammal

    The color of the animal can be varied.

    • Plain (gray, pink, black).
    • Two-tone (black and white shades).

    These mammals are very nimble and energetic, they move through water at high speed causing the top layers of skin to wear away. Therefore, dolphins have a deep layer of skin that is constantly renewed. This process is very fast; the upper and lower layers change within a day. Skin cells are constantly dividing, and about 30 layers of skin can be replaced in a day. Continuous molting is the main condition of these intelligent mammals.

    Intelligence

    A little known but much discussed aspect is how intelligent these animals are. Almost the entire life of a mammal - free time when they can do whatever they want. He spends it on fun games, communication and even sex. Mammals love to jump out of the water, spin and twist in every possible way. Despite their carefree existence, dolphins are considered very smart mammals, because they are able to communicate, think, follow commands, and even save people.

    The brain of an animal, in relation to the proportions of the body, is large, and if compared with monkeys, dolphins are much larger. Also, thanks to research by scientists, it was revealed that the mammal has a highly developed vocal vocabulary. Not to mention self-awareness, emotional empathy, social development, mutual support and mutual aid.

    Nutrition

    The main food of dolphins is undoubtedly fish. The animal prefers to eat small fish such as anchovies and sardines.

    It should also be said about how they catch their prey. First a school of dolphins use their main weapon - echolocation scanning the water for fish. Further, if a jamb is detected, they high speed approaching, while giving such sound signals that the fish panic and huddle together in a compact heap. This is where smart mammals know their stuff. Together, they catch prey. The possibilities of such a hunt are great. Mammals are capable of catching almost the entire school of fish.

    Reproduction

    Dolphins reproduce throughout the year. They mate in motion, and the birth of offspring also takes place in motion.

    Pregnancy in a female lasts from 10 to 18 months. Usually, a baby is born about 60 cm in length, tail out. The newborn is so developed that from the very first minutes he begins to follow his mother. While learning in its pack, the animal becomes smarter, develops, learns to hunt fish, communicates, and soon gets its own food.

    Animal enemies

    The most evil The enemy of the dolphin, like all inhabitants of the ocean, is considered to be the shark, as well as some relatives of the mammal (killer whale). Since ancient times, people began to hunt dolphins. The indigenous people of the north caught the mammals and extracted only the meat. This is a high degree of cruelty. Currently, in some countries, the barbaric tradition of hunting dolphins remains.

    These mammals are dying due to human activities. Animals often get caught in fishing nets. They die from oil spills into the sea. Injuries caused by ship propellers affect the lives of dolphins and their deaths. Man contributes to all this, even if unconsciously, but he has made a lot of efforts that contribute to the destruction of dolphins. But some of them are already listed in the Red Book.

    Dolphinariums, water parks with complex animal training, everything this contributes to the destruction of these intelligent mammals. This is worth thinking about.

    Dolphins are one of the most mysterious animals on our planet. The intelligence of these sea inhabitants is considered so high that they are called “people of the sea.” Scientists say that dolphins are smarter and smarter than all other animals.

    Dolphins live in water, but they are not fish, but mammals from the order Cetacea. That is, they need air - they breathe with their lungs, not their gills. People can always see dolphins' faces on the surface of the sea because dolphins can stay underwater for an average of about 3-5 minutes (although dolphins have been recorded underwater for 10 to 15 minutes). Dolphins feed their young with milk.


    Dolphins are found in many seas and oceans of the world, including the Black Sea.
    Dolphins live up to 75 years, most often about 50, in captivity usually about 30. With the help of its 88 teeth, the Black Sea dolphin eats about 30 kg of fish per day, the mass of dolphins is up to 500 kg. The body temperature of a dolphin is the same as that of a person - 36.6 degrees. The gestation period of dolphins is about 12 months. The female dolphin usually brings one calf 50-60 cm long and carefully guards it for some time.


    When you mention a dolphin, you are more likely to think of the species Bottlenose Dolphin (Tursiops truncatus). Bottlenose dolphins owe their popularity partly to numerous references in cinema and fiction and their high ability to learn.


    The skin of dolphins is a miracle of nature; they are able to dampen the turbulence of water near the surface of a fast-swimming body, which reduces the speed of movement - submarine designers learned from dolphins, creating artificial skins for submarines. And the feeling of dolphin skin to the touch is completely unusual, and also brings joy: it looks dense, like it’s made of plastic, but when you run your palm over it, it’s tender and soft, it seems like thin silk.


    When dolphins began to be studied and trained in the middle of the last century, the first results of this work seemed so unusual, and even surprising (they talked about it a lot, wrote about it and made films) that a legend gradually developed about the unusually high intelligence of dolphins; one could often hear that they were no more stupid than a person, only their minds were different.


    The brain of an adult dolphin weighs about 1,700 grams, while that of a human weighs 1,400. A dolphin has twice as many convolutions in the cerebral cortex. At the same time, there are relatively few neurons per cubic millimeter of its substance (less than in the brain of primates).


    The results of studies on the behavior and physiology of the brain of dolphins are very contradictory. Some put their ability to learn at about the level of a dog and show that dolphins are very far from chimpanzees. Research on the communication methods of dolphins, on the contrary, leads to the conclusion that we have not yet come close to understanding this form of life in natural conditions and it is simply incorrect to compare the level of intelligence of dolphins and chimpanzees. One property of the dolphin brain is completely unique: it never really sleeps. The left and right hemispheres of the brain sleep alternately. The dolphin needs to come to the surface from time to time to breathe. At night, the waking halves of the brain are responsible for this, in turn.


    The language of dolphins can be divided into 2 groups: Body language (body language) - various poses, jumps, turns, various ways swimming, signs given by the tail, head, fins.


    The language of sounds (language itself) is a sound signaling expressed in the form of sound impulses and ultrasound. Examples of such sounds include: chirping, buzzing, squealing, grinding, clicking, smacking, squeaking, popping, squeaking, roaring, screaming, screaming, croaking, and whistling.

    The most expressive are whistles, of which dolphins have 32 species. Each of them can denote a specific phrase (signals of pain, anxiety, greetings and a calling cry “come to me,” etc.). Scientists studied dolphin whistles using the Zipf method and obtained the same slope coefficient as that of human languages, that is, they carry information. Recently, about 180 communication signs have been discovered in dolphins, which they are trying to systematize, compiling a dictionary of communication between these mammals. However, despite numerous studies, it has not been possible to completely decipher the language of dolphins.


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


    Scientists captured 14 light gray bottlenose dolphins in the wild and recorded the various sounds these mammals made as they communicated with each other. Then, using a computer, “names” were extracted from the records. When the name was “played” for the flock, a specific individual responded to it. The dolphin’s “name” is a characteristic whistle, the average duration of which is 0.9 seconds.

    Everyone has heard that sometimes dolphins and other whales wash ashore. Sometimes this happens due to illness, poisoning or injury. There is another hypothesis that explains the reason for this strange behavior dolphins: it turns out that with a certain shape of the coast, composed of certain types of sediments, among the cacophony of sounds generated by the surf, sometimes a sound arises that exactly corresponds to the cry of a dolphin for help. Animals, hearing these sounds, instinctively rush to help - and end up on the shore.


    Dolphins eat fish. A lot of fish: each member of the flock should eat 10-30 kilograms per day. Dolphins are warm-blooded and need to maintain a high body temperature, sometimes in very cold water. The subcutaneous layer of fat also helps with this - it acts as a heat insulator and source of energy for the intracellular oven: burning fats and carbohydrates with the release of thermal energy. Fuel reserves need to be replenished all the time, so they constantly hunt. They catch up with a school of fish - no one in the sea swims faster than them - and surround it. If this happens very close to the shore, the dolphins form a semi-ring and press the fish to the beach; compressing their hunting formation, they push the fish into the shallowest water and eat it there - while they swim into the very waves of the surf, so shallow that their dorsal fins stick out of the water, and their pectoral fins touch the sand at the bottom.


    Having surrounded a school of fish further out into the sea, the dolphins do not rush, each individually, after the prey, but organize the school in a ring, preventing the fish from scattering, and one by one plunge into the school. Having caught prey, they return to their place in the pen.

    Where there are fish, there are dolphins. U Black Sea coast the fish are most abundant in spring and autumn - when schools of mullet and anchovy go to the Sea of ​​Azov for summer feeding, or return to winter in the Black Sea - along the coast of the Caucasus. Therefore, dolphins most often appear here in April-May and September-October. And in fact Kerch Strait– gate Sea of ​​Azov– hundreds of dolphins stand at the outpost, meeting migrating fish stocks.


    In summer, bottlenose dolphins also often come straight to the beach - they are more often seen in the early morning or afternoon - perhaps because there are fewer swimmers at this time.

    Dolphins live in schools, in which everyone is relative, which is why their mutual assistance is so well developed. They always help a weakened dolphin stay near the surface so that it does not choke; There are stories of how dolphins came to the aid of drowning people. They never act hostile. Dolphins learn tricks very quickly - they only need one correct execution of an exercise on a signal, for which they are rewarded with a fish, so that the skill is fixed in memory. True, they also easily forget their skills if the coach forgets to reinforce a useful habit.


    Dolphins live for about 30 years. Dolphins are born approximately once every two years. At this time, the dolphin tries to jump high so that the calf can take its first breath. Dolphins are very touching parents, caring for their young for about five years. And even when reaching puberty, the cub still remains strongly attached to its mother and tries to follow her everywhere.


    For a long time, scientists were puzzled by the question of how dolphins sleep. After all, in the sea you can easily drown or become a victim of attack by other predators. However, it has now turned out that the sleep of dolphins is not similar to the sleep of ordinary animals - during sleep, one hemisphere of the dolphin rests, and the other is awake. Thus, the dolphin is always in control of the situation and, at the same time, gets complete rest.

    Definitely, something makes us treat dolphins differently than other animals - “friends of man”... Friendly, cheerful, cute... They are really friendly and curious: they are not afraid to swim up and play with a person, although more often - or not pay attention to people, or simply swim away - they have their own worries at sea. Maybe it's the dolphin's smile? After all, they always smile - for some reason, that’s how their face is structured (I don’t even want to call it a muzzle!). And this smile with big eyes- one of those smiles that make us involuntarily smile back - not all people know how to smile like that.