Whale - fish or mammal? This question worried scientists long before the advent of modern science. In particular, this task was trying to solve such a genius of thought, as Aristotle. And at the same time he came to the same opinion as our contemporaries. But let's get everything in order.
The whale is the most majestic inhabitant of water. No living creature can compare with its size and grace, not to mention its amazing ability to sing songs. But what else do we know about these incredible creatures?
Who is a whale?
So, what is the meaning of the word whale? According to the dictionary, it is a large mammal living in the sea. That is, today, unlike past times, it is much easier to find a solution to such a confusing question. But how did it happen that the ancient descendant of whales wanted to exchange land for the ocean?
Well, scientists still do not know the whole truth. However, it is precisely known that 60 million years ago the progenitors of all cetaceans first went to look for food back into the water. Perhaps this was due to their prolonged drought, which destroyed part of the vegetation on the planet or a great deal of competition from other animals. But the fact remains that the ancestors of the whales no longer wanted to go back to dry land.
How did the land animal adapt to life under water?
It should be understood that such a metamorphosis did not occur in one or two years. Evolution is a chain of small changes, thanks to which for thousands of years a living organism constantly mutates. And this ultimately produces a completely new species, radically different from its ancestors.
Yet, after 60 million years, researchers still find echoes of those ancient times in the skeleton of a whale, when it still walked on its four legs on dry land. For example, it has a hip bone, which is located in its back part of the body. As well as its front fins have a similar bone structure with most of its hoofed ones.
After a series of studies, scientists came to a curious conclusion. It turns out that the closest relatives of cetaceans are hippos. And if you look closely, then a certain similarity in their behavior can be seen even today. In particular, their great passion for water.
Family of Cetaceans
It should be noted that the whale is not the only representative of its family. Dolphins and porpoises are also included in the category of marine mammals. How do they differ from other inhabitants of the water depths?
- First, all cetacean warm-blooded, unlike fish. That is why they so badly need a good fat layer that can protect them from the cold of the underwater kingdom.
- Secondly, this family is not able to extract oxygen from water. Therefore, they must constantly float to the surface in order to replenish their supply of air in the lungs.
- Third, they all feed their children with milk. And although over the years of evolution this process has slightly modified, cetaceans are still mammals.
The whole family is divided into three large subgroups:
- Baleen whales (Mysticeti) - the largest squad of the family. Its distinctive feature is a special whalebone filtering organ, which is located on the upper jaw of the animal. Its main task is to filter plankton from excess impurities.
- Toothed whales (Odontoceti) - by and large predators hunting squid and small fish. This species is able to navigate in water using echolocation.
- Ancient whales (Archaeoceti) - unfortunately, not a single representative of this category could survive until our days.
Whales: general information
Among all the inhabitants of the planet Earth is the whale - the largest mammal. On average, an adult can reach 25 meters in length. For comparison, about the same occupy 4 large buses, if you put them in one row. It is not surprising that such a large object weighs about 90-110 tons, and some even more.
These giants live in almost all the oceans of the planet. What is true, depending on the season, they can migrate from one place to another. This behavior is due to the fact that the whales are sensitive to water temperature, and therefore they spend the winter closer to the tropics.
In general, among all members of this family, two special subspecies can be distinguished: blue and gray whales. By and large, this division is due to the skin color of these animals, but there are other, no less important differences.
Echoes of the past
The gray whale is the oldest representative of this family. Scientists have found the remains of these animals, which according to approximate analyzes were about 30 million years. Previously, these giants lived in almost all corners of the globe, but now they can be found only in the northern part of the Pacific Ocean.
These creatures used to live in small groups, about 2-3 individuals in each. Although it is often possible to meet a lonely whale, proudly plowing the expanses of water. And yet most giants prefer to live in a group. By and large, this is due to the fact that gray whales have very strong family ties.
Probably, it was this connection that helped them survive the dangerous times. Indeed, in the middle of the XX century, they were almost completely destroyed by whalers, hunting for their fat. So, according to scientists, in 1946 the number of these mammals was reduced to 250 individuals. Only thanks to the miracle and efforts of animal rights activists was it possible to avoid a tragedy. Now the number of these animals has increased to 30 thousand, which gave them a new hope for a better future.
The blue whale is the largest creature on earth
As for the blue whales, they are rightly considered the largest creatures on this planet. Even such a huge animal, like an elephant, cannot bear with them. Such dimensions are reminiscent of the fact that once similar giants walked all over the earth. Now the blue whale is the only representative of the ancient gigantic animals.
This animal is not particularly favored by people, and therefore rarely approaches the coast. His favorite environment is the open ocean, where he feels truly free. It moves quite slowly, with only a speed of 10-12 km / h, but in case of danger, it can increase three times.
Like all members of its species, the blue whale feeds on plankton. And although this animal has already changed land for a long time to water, it still cannot remain in it all the time. That is why whales so often float to the surface, while releasing fountains of water from a special hole located on the upper part of the body.
Whales are marine animals, whose numbers often decreased to catastrophic levels. This is caused by people hunting their meat and fat. They are the main culprits of these tragedies, but not the only ones.
Another factor affecting the population of any species is its ability to reproduce. So, the problem is that these creatures give birth to offspring no more than once every one or two years. And at the same time the female gives birth to only one kitten, at least - two. However, depending on the subspecies of whales, pregnancy can last from 9 to 18 months.
Pleasant is the fact that the mother is always very careful with her cub. Those, in turn, grow very quickly and gain weight. Thus, on average, a baby hut can gain about 50 kg of live weight per day. Therefore, it is not surprising that for some seven months it can reach up to 14 meters in length and weigh 20-25 tons.
Although whales come to puberty at the age of 4-5 years, they become full-fledged adults only in the 14th-15th year of their lives.
Whale: Interesting Facts
Few know that:
- Whales are the only ones who can sing except for man. And although it was previously believed that only males have this ability, recent studies have proven the opposite. So, the whale females also sing songs, especially to young cubs.
- A full whale blue stomach can hold up to two tons of live food. For example, the average fishing boats take as much of the catch.
- If we talk about the weight of the whale, it should be remembered that one of his tongue weighs about 3 tons. As for the other organs, for example, the heart can reach 600-700 kilograms.
- Although the whale has a hip bone, it is completely useless. Moreover, it does not even connect with the main part of the skeleton.
Well, the answer to the question “Whale is a fish or a mammal?” Was given above. Now we can talk about the types of these creatures.
For a start, it is worth noting that all whales are descendants of land mammals. And those who belonged to detachments of the artiodactyls! This is not fiction, but a scientifically proven fact that was established after molecular genetic examinations. There is even a monophyletic group (treasure), combining the whales, hippopotamuses and all of the close-toes. All of them are cephalopods. According to research, whales and hippos descended from the same creature that lived on our planet about 54 million years ago.
So, now - about the species of whales. Or rather, about the sub-detachments. The first species is baleen whales. They are the largest of modern mammals. Their physiological characteristics are the whiskers with a filter-like structure.
The second species is toothed whales. Carnivorous, fast creatures. They excel toothless whales. In size only sperm whales can compare with them. And their peculiarity, as it was already possible to guess, is the presence of teeth.
And the third species is the ancient whales. Those that no longer exist. They belong to the paraphyletic group of animals from which modern species of whales later descended.
Now it is worth considering the description of the whale from a physiological point of view. This animal is a mammal, and warm-blooded. Accordingly, every whale breathes with the help of the lungs, and the females feed their babies with milk. And the hairline of these creatures has, albeit reduced.
Since these mammals are exposed to the sun, their skin is protected from ultraviolet rays. True, in each species it is expressed in different ways. The blue whale, for example, can increase the content in its skin of special pigments that absorb radiation (in simple terms, it “tans”). The sperm whale is protected from oxygen radicals by triggering a “stress response”. Finwal practices both methods.
By the way, these creatures maintain their warm-bloodedness due to the presence of a thick fatty layer under the skin. It is he who protects the internal organs of marine animals from hypothermia.
Oxygen uptake process
It is interesting to talk about how whales breathe. These mammals can be under water for at least 2 minutes and a maximum of 40. However, there is a record holder, and he is a sperm whale, who is able to stay under water for 1.5 hours.
The outer nostrils of these creatures are located at the top of the head. They have special valves that reflexively close the airways when the whale sinks into the water. At the time of diving they open. It is important to know that the airway does not connect to the esophagus. So the whale absorbs the air safely, without harm to itself. Even if there is water in his mouth. And by the way, speaking about how whales breathe, it is worth noting that they do it quickly. Speed contributes shortened bronchi and trachea. By the way, their lungs are very powerful. In one breath, the whale refreshes the air by 90%. And the man - only 15%.
It is worth noting that through the nostrils (also called breathing) at the time of diving a column of condensed steam escapes. The same fountain, which is the hallmark of the whales. This is due to the fact that the whale exhales out of itself warm air, which is in contact with the outside (cold). So the fountain is the result of temperature exposure. A column of steam in different whales differs in height and shape. The most impressive are the "fountains" of large mammals. They come out of their breathing with such tremendous power that it is accompanied by a loud trumpet sound. In good weather, it can be heard from the shore.
A few words should be told about what whales feed on. The diet of animals varied. Toothed whales, for example, consume fish, cephalopods (squid, cuttlefish) and in some cases mammals.
Baleen representatives feed on plankton. They absorb a huge amount of crustaceans, filtering it from water or with a whisker. Small animals, these animals can also eat.
The most interesting thing is that whales hardly eat in winter. And for this reason, in the summer, they continually absorb food. This approach helps them to accumulate a thick layer of fat.
Food, by the way, they need a lot. Large whales consume about three tons of food per day.
Blue whale deserves special attention. This is the largest animal of all ever existed on our planet. It reaches a length of 33 meters, and weighs about 150 tons.
By the way, the blue whale is a representative of the baleen sub-order. It feeds on plankton. He has a well-developed filtering apparatus, due to which he filters the absorbed mass inside.
There are three subspecies of this animal. There is a dwarf, southern and northern whale. The latter two live in cold circular waters. Dwarf is found in tropical seas.
It is believed that blue whales live for about 110 years. In any case, so much was the most adult individuals, met people.
Unfortunately, the blue whale is not such a frequent marine inhabitant. In the XX century uncontrolled hunting was opened on these animals. By the middle of the last century, only 5,000 individuals remained in the world. People committed a terrible act, destroying them. Emergency security measures were taken. At the moment, the number of individuals has doubled, but blue whales are still at risk.
This is a representative of the toothed whales of the family Narwhal. Belukha is not very big. Its mass reaches only 2 tons, and its length is 6 meters. The beluga has excellent hearing, keen perception of any sounds, as well as the ability to echolocate. Moreover, these are social beings - there are cases in which these whales saved a man. In the oceanariums, they get along perfectly well, eventually get used to people, and even become attached to workers.
Their diet is varied. Belugs eat cod, flounder, herring, mollusks, seaweed, shrimp, lamprey, jellyfish, rib robes, pink salmon, gobies, doggy, crayfish and many other marine life that can be eaten.
These creatures, like many others, also suffered because of human cruelty. Whalers easily drove them to the shallows, and belugas literally broke up. But at the moment this species is gradually recovering its numbers. It remains to hope that people will not spoil anything.
There are dozens of other cetacean species, and all are special and interesting in their own way. And I want to hope that every species that we know will remain. The marine world should not lose any of them, since each of them is a real miracle and natural value.
Kit - photos, descriptions, characteristics of the animal. What does a whale look like?
The whale is not a fish, but a mammal.
Surprisingly, but a fact: not only whales, but also all representatives of the order of cetaceans (dolphins, porpoises) evolved from land-hoofed animals. Whales look like fishes in appearance, but the closest modern relative of whales is hippopotamus, and their common ancestor trampled our planet 54 million years ago. After 5 million years, the whales finally migrated to the water element.
Whales are distinguished by gigantic body sizes, the largest among all mammals. And yet the weight and length of the body depends on the species. For example, the size of a blue whale (the largest mammal in the world) is 33 meters, and the whale weighs about 150 tons. In this small dwarf whale weighs only 3-3.5 tons and has a size of 4-6 meters in length.
Unlike fish, whales are warm-blooded animals that are able to maintain a constant body temperature regardless of the environment. An impressive fat layer protects animals from hypothermia and maintains a constant body temperature of about 35-40 degrees.
Whales breathe not with gills, but with lungs. The whale has no gills, but there are powerful lungs with well-formed muscles, thanks to which whales carry 90% of the air in one breath / exhale (for comparison, humans only have 15% air). Therefore, whales, depending on the species, are able to stay in the water column from 10 to 40 minutes, and the sperm whale has enough air for 1.5 hours.
When the whale rises to the surface, the air exhaled from the nostrils (breathing) is much warmer than the surrounding air, thereby forming a fountain - a condensate column, which is different in shape and height for different whales. In large species, the fountain is pulled out with such power that it produces a pipe drone, which can be heard for several kilometers.
All whales are distinguished by an elongated, drop-shaped (spindle-shaped) body, which provides animals with minimal water resistance during the swim. The massive head of the animal ends in a blunt, narrow, or pointed rostrum - “beak”. На черепе расположены ноздри, смещенные к темени.
Глаза китов по отношению к телу имеют совсем небольшие размеры: у крупных видов глаз весит до 1 кг, причем размер глаза кита может составлять 10-17 см в диаметре. У маленьких китов размер глаза соответствует глазу собаки.
Анатомически у кита есть зубы, но у некоторых видов они находятся в неразвитом состоянии. In toothless baleen whales, teeth are replaced by bony plates, called whalebone and adapted for filtering food. And only representatives of toothed whales grow the same cone-shaped teeth.
The whale's spine can contain from 41 to 98 vertebrae, and thanks to the spongy skeleton structure, the elastic intervertebral discs give the body of animals special maneuverability and plasticity.
There is no cervical interception, and the head smoothly passes into the body, which noticeably narrows to the tail. The pectoral fins of the whale are modified and turned into fins, performing the function of taxiing, turning and braking. The tail section of the trunk is flexible and muscular, has a slightly flattened shape and performs the function of the motor. At the end of the tail are the blades having a horizontal location. Most species of whales have an unpaired dorsal fin, which acts as a stabilizer when moving in the water column.
Whale skin is smooth, hairless, only baleen whales face grow single hairs, bristles similar to vibrissae of land animals. The color of the whale is monotonous, spotty or protivoleenovoy, when the top of the animal is dark, and the bottom is light. In some species, the color of the body changes with age.
Due to the lack of olfactory nerves, the whale's sense of smell is almost completely lost. Taste receptors are poorly developed, so, unlike other mammals, whales only distinguish salty taste. Whales have poor eyesight, most of these animals are near-sighted, but they have conjunctive glands that are absent from other animals.
As for the whale's hearing, the complex anatomy of the inner ear allows the whales to distinguish sounds in the range from 150 Hz to the lowest ultrasound frequencies. And due to the richly innervated skin, all the whales are distinguished by excellent touch.
Whales communicate among themselves. The lack of vocal cords does not prevent whales from speaking and making special sounds using the echolocation device. The concave bones of the skull, together with the fat layer, act as a sound lens and reflector, directing the beam of ultrasonic signals in the right direction.
Most whales are rather slow, but if necessary, the whale's speed can be 20–40 km / h.
The life span of small whales is about 30 years; large whales live up to 50 years.
Where do whales live?
Whales inhabit all oceans. Most species of whales are herd animals and prefer to live in groups of several tens or even thousands of individuals. Part of the species is subject to constant seasonal migrations: in winter, whales swim to warm waters, where the births take place, and in summer they grease in temperate and high latitudes.
What does a whale eat?
Most whales feed on a specific feed:
- planktophagous they eat only plankton,
- tetophagi prefer to eat cephalopods,
- ichthyophagous eat only live fish
- saprophages (detritophages) consume decomposed organic matter.
And only one animal from the order of cetaceans, the killer whale, feeds not only on fish, but also on pinnipeds (seals, sea lions, penguins), as well as other whales, dolphins and their young.
Killer whale swims behind the penguin
Types of whales with photos and names.
The modern classification divides the order of cetaceans into 2 main suborders:
- toothless or whiskered whales (lat. Mysticeti),
- toothed whales (lat. Odontoceti), to which dolphins, killer whales, sperm whales and porpoises belong.
The order of cetaceans forms 38 genera, in which more than 80 known species are combined. Among such diversity there are several varieties:
- Humpback whalehe humpback or long-armed whale(lat. Megaptera novaeangliae) got its name due to the convex fin on the back, resembling a hump. The length of the body of the whale reaches 14.5 meters, in some specimens - 18 meters. The average weight of a humpback whale is 30 tons. It differs from other representatives of the family of stripy humpbacks by a shortened body, a variety of colors and several rows of warty leathery protrusions on the crown of the head. Humpback whales inhabit the entire World Ocean, except for the Arctic and Antarctic. Representatives of the North Atlantic population feed exclusively on fish: capey, navaga, mintay, sardines, herring, haddock. The remaining whales eat small crustaceans, various mollusks and small schooling fish.
- Gray whale (california whale) (lat. Eschrichtius robustus, Eschrichtius gibbosus) - one of a kind species of whales, practicing eating food from the ocean floor: the animal plows the silt with a special outgrowth in the form of a keel, located under the lower jaw. The basis of the food of the gray whale is made up of many organisms that live on the bottom: annelids, snails, bivalves and other mollusks, crayfish, egg-caps and sea sponges, as well as small fish species. Gray whales in adulthood have a body length of up to 12-15 m, the average weight of the whale varies from 15 to 35 tons, and the females are larger than the males. The body is brown-gray or dark brown, resembling in color rocky shores. This species of whales lives in the Sea of Okhotsk, the Chukchi and Bering seas, migrates to the Gulf of California and to the southern shores of Japan in winter. Gray whales - champions among animals for the duration of migrations - the distance covered by animals can reach 12 thousand km.
- Bowhead whale (polar whale) (lat. Balaena mysticetus) - long-liver among mammals. The average age of a polar whale is 40 years, but the known, scientifically based fact of longevity is 211 years. This is a unique species of baleen whales that spend their entire lives in the cold waters of the Northern Hemisphere, often working their way like an icebreaker. The whale's fountain rises to 6 m in height. The length of the body of mature females reaches 20-22 meters, males - 18 meters. The weight of the whale is from 75 to 150 tons. The skin color of the animal is usually gray or dark blue. The belly and neck are lighter in color. An adult bowhead whale consumes almost 2 tons of different food every day, consisting of plankton (crustaceans and wing-legged mollusks).
- Sperm whale(lat. Physeter macrocephalus) - the largest representative of toothed whales, and females are much smaller than males and have a body length of not more than 15 meters. Keith male grows up to 20 meters in length. The maximum weight of females reaches 20 tons, males - 50 tons. Sperm whales have such a distinctive appearance that they cannot be confused with other cetaceans. The giant head is more than 35% of the length of the body, and, when viewed from the side, the muzzle of the sperm whale looks like a slightly beveled rectangle. In the recess at the bottom of the head there is a mouth, seated with 20-26 pairs of cone-shaped teeth. The weight of 1 tooth of a whale reaches 1 kilogram. The wrinkled skin of a sperm whale often has a dark gray color with a blue tint, although dark brown and even black individuals are found. Being a predator, the whale sperm whale hunts for squid, cuttlefish, large fish (including some species of sharks), and also swallows all objects in the ocean: empty bottles, rubber boots, toys, hanks of wire. Sperm whales live throughout the oceans, but in tropical waters are more common than in cool. Most of the population is distributed off the coast of the Black continent and the east coast of Asia.
- Finval(lat. Balaenoptera physalus) - the second largest animal of the planet. The length of an adult whale is 24-27 m, but thanks to a slender physique the whale weighs only 40-70 tons. A distinctive feature of the finval is the asymmetric color of the muzzle: the right side of the lower jaw is white and the left is dark. The basis of the nutrition of the whale is small crustaceans. Finlals live in all oceans: in winter they inhabit waters of moderately warm belts, and in the warm season they float to the waters of the Arctic and Antarctic.
- Blue whale (blue whale, blue whale)(lat. Balaenoptera musculus) - not only the biggest whale in the world, but also the largest animal of our planet. The length of the blue whale can reach 33 meters, and the weight of the blue whale reaches 150 tons. This animal has a relatively slim build and a narrow muzzle. The body color inside the species is monotonous: the majority of individuals are gray with blue tint and gray spots scattered throughout the body, due to which the skin of the animal appears to be marble. The blue whale feeds mostly on plankton and inhabits the entire World Ocean.
- Dwarf whale (dwarf smooth whale, short-headed smooth whale)(lat. Caperea marginata) - the smallest variety of baleen whale suborder. The body of an adult individual does not exceed 4-6 m in length, and the whale's body weight barely reaches 3-3.5 tons. The skin color is gray with dark spot, sometimes black. Distinguished by an unusual for whales undulating method of movement, eats plankton. Dwarf whale - one of the rarest and smallest species of whale, lives mainly in the waters of southern Australia and New Zealand.
What is the difference between a whale and a sperm whale?
Sperm whale is a type of whale. It has its own specific features:
- The head of the sperm whale with a huge square forehead occupies from 1/4 to 1/3 of the length of the body. The head of the other whales is relatively small: from 1/5 to 1/9 of the body length. The exceptions are some representatives of baleen whales, such as the bowhead whale, southern whale, whose head and body sizes are in the same proportion as those of sperm whales.
- The nostrils of the whales are shifted back and up. They can be paired (in baleen whales) or unpaired (one nostril) (in toothed whales). In the sperm whale the nostrils are asymmetrically arranged and moved forward, one of which performs the respiratory function, and with the help of the other it makes sounds.
- Sperm whale belongs to the suborder of toothed whales, and its jaws are armed with numerous cone-shaped teeth. Mammals of the suborder of baleen whales instead of teeth have horny plates replacing their teeth and called whalebone.
- In sperm whales in the head is a huge spermaceti organ filled with fatty substance (spermaceti), solidifying at a low temperature. It is assumed that this organ helps the animal to dive and rise to the surface. Unlike sperm whales, the rest of the whales do not have such an organ.
- The next difference is the dorsal fin. The whales are single. In sperm whales, it has an unusual structure for other whales - a small crest, followed by several of the same, only smaller ones.
- The sperm whale is capable of diving to a depth of 3,000 m, which is much more than other whales. Under water, it is longer not only other cetaceans, but all living creatures on the planet, breathing atmospheric air.
- Sperm whale, like other toothed whales, feeds mainly on cephalopod mollusks, in particular, squid and, in smaller quantities, fish, including deep-sea one, snapping at their jaws. Baleen whales feed on plankton, small fish and other small vertebrates, filtering them out of the water through the whalebone.
- The pregnancy of sperm whales is longer than that of other cetaceans, and lasts 16-18 months.
- All whales feed their young underwater. After a certain time interval, babies capture the mother’s nipple for a few seconds. In this case, the young of all whales hold it between the tongue and the top of the sky, and the sperm whale cub holds it in the corner of the mouth.
- Sperm whales produce echolocation signals: clicks, pops and creaks. Baleen whales, in which echolocation is not developed or is in its infancy, can make various sounds. For example, a growl, a roar, a groan, a purr may emit a bowhead whale, humpback songs are like sounds of wind instruments, the groans of the fin whale resemble the sound of a flute from high to low tones. Many representatives of toothed whales emit the same sounds as sperm whales, but at the same time are able to whistle, roar, and killer whales also scream like March cats.
- Whales swim faster than sperm whales, reaching speeds of over 50 km / h. The maximum speed of sperm whales rarely exceeds 37 km / h, and mostly does not exceed 10 km / h.
What is the difference between the killer whale and the whale?
Killer whale, like whales, belongs to the order of cetaceans, but it has certain features:
- Killer whales are different from other whales by their high dorsal fin, reaching 1m in height. Moreover, the fin males are higher than the females.
- In killer whales, as opposed to other whales, the head shortens with age and the tail section lengthens, that is, the tail grows faster than the head.
- Whales feed on plankton, small vertebrates, fish, cephalopods. Killer whales, who at a young age also eat fish and mollusks, subsequently become real predators attacking warm-blooded animals. They eat sea lions, sea lions, elephant seals, porpoises, seals, walruses, and even their cetaceans. They swallow small prey whole, and large prey in large chunks.
- Whales are quite melancholic and slow animals. These sometimes clumsy sea giants are ready to filter the water for hours, extracting krill from it. The Killer Whale is a swift and very active predator, deftly hunting its prey swimming near.
- Killer whales have a strong attachment to each other and to their young, and their flock is difficult to separate. Many other whales are solitary or gather in small groups of 3-4 individuals.
Whale - fish or mammal: a scientific rationale
Since childhood, everyone remembers Ershov's fairy-tale-hunchbacked fairy-tale, which mentions the “wonder-yudo whale fish,” and the definition of fish in the same bundle with a whale is mentioned in folklore of various nations, among people whales are called giant fish. ... And then at school we are told that the whale is a mammal, the largest of all living on Earth. Where is the truth, and where did the delusions come from?
The fact that the whale is a fish, only a giant, people thought in antiquity. Their judgments were based only on the external similarity of whales and fish, as well as on the fact that they live exclusively in water. At the same time, even Aristotle assumed that whales and dolphins are mammals, only then his judgments did not have weighty evidence, therefore they were questioned.
Later, people had new and new opportunities to explore in detail the way of life of the whales, as well as their physiology.
Before we talk about why whales are mammals, let us designate who the mammals are in principle. The definition lies on the surface and lies in the very word: mammals are those who feed on milk, or to be more precise, those who are fed with milk.
So, during the observation of the whales, it was found that the females give birth to live young, and then fed them with milk, which already gives every reason to speak of them as mammals. Fish, on the other hand, spawn, from which later their offspring emerge, and of course, there is no question of any milk feeding in fish.
In addition to the cetacean family, mammals living in the sea and on the coast include pinnipeds (seals, walruses), bears (polar bears), martens (sea otter, sea otter), sirens (dugongs, manatees).
Another significant difference between whales and fish is that the former breathe air. That is, they can not always be under water. Periodically (at least once every two hours), whales float to the surface to collect air into the lungs. For this purpose, a special opening is located on the top of their head, called the breather. In one breath, the whale captures about 2000-3000 liters of air. For comparison, it should be said that the average human lung volume is 4-6 liters.
The largest mammal on Earth has not only the largest brain, but also the highest level of intelligence. People do not understand the language of the whales and what they sing their songs about, but the fact that they have a certain meaning in them is indisputable. In addition, despite the awesome size, whales are kind animals, safe for their marine relatives and people.
A high stream of water (up to 15 meters), which can be seen above the surface of the water, is formed when the whale exhales.
It may be asked how a female whale feeds her cub with milk under water. Everything happens as follows: the kiten embraces the nipple, and the mother literally injects milk with a strong jet. If the whale feeding process took place on land, the milk jet would beat 2 meters ahead! Whales grow by leaps and bounds, by hours, gaining about 3 kilograms per hour in weight, and all because milk is very nutritious, the percentage of fat content in it approaches 50.
By the age of seven months, the baby whale turns into a big whale, the real master of the ocean. The blue whale is the largest animal ever lived on Earth, its size exceeds even the long-extinct dinosaurs. In order to make it clearer, imagine the weight and height of a whale in relation to people and buses. Thus, a medium-sized whale weighs as much as 2,000 people, and its length is approximately the same as if it were to line up four large long-distance passenger buses. The dimensions of the internal organs of the whale are also the largest of all animals. Imagine that only one whale tongue weighs as much as an Indian elephant. In order to get enough, the whale needs about a ton of food per day. Animals eat mainly fish. Seeing the swimming school of fish, the whale wedges in its middle, beats with its powerful tail to stun the fish, and then swallows it. Даже несколько странно, но гроза океанов не представляет ровно никакой опасности ни другим морским животным, ни людям, охоту киты не ведут ни на тех, ни на других, хотя сами нередко становятся желанной добычей браконьеров и касаток.
Известно, что у китов очень слабое зрение, отсутствует обоняние, зато обострено восприятие звука. Все, что им нужно знать о жизни океана, они воспринимают на слух. Да и музыкальный слух у этих величественных животных определенно присутствует.
But let's not talk about sad things, but rather continue to give evidence of why the whale is not a fish.
Among scientists there is a theory that once upon a time, about 60 million years ago, the ancestors of whales walked on land on four paws. Then they no longer have enough food, and to get it, they went to the ocean. After there was no food left in the coastal zone, they had to adapt to life under water. Of course, this is not about years, or even centuries, but millennia, during which animals gradually evolved. Evidence that the whales were once land animals is the fact that their fins are similar in structure to the five-fingered hand, and there are bones on the body resembling the anatomy of the hind legs.
Whales, like all other mammals, are warm-blooded, but at the same time they live in icy water. What allows them not to freeze? This so-called blubber is a thick layer of subcutaneous fat that heats no worse than a fur coat.
There is a legend among the peoples of the North, according to which whales are relatives, progenitors of man. There is no scientific evidence of this, so believing or not believing myth is a private matter for everyone. But one thing is certain: whales are the only mammals, besides humans, that can sing. The sounds that they make are unique, melodic and so organized as if this is actually a song released from the pen of some eminent composer. At first, it was believed that only males sing and do it exclusively during the mating season in order to attract the attention of females. But then it turned out that females also know how to sing to their newborn whales, like people performing lullabies to babies.
If earlier you had a question: a whale is a fish or an animal, now you can definitely answer it, supporting your opinion with scientific facts. It remains to wish for interesting discoveries in the further study of the amazing life of the animal world!