Is a whale a fish or a mammal? Types of whales. What do the whales eat and how do they breathe?
The whale is a sea monster. In the literal sense of the word. After all, this is how the Greek word is translated, from which came the name of this amazing animal - κῆτος. Much can be said about cetaceans belonging to the order. But dwell on the most interesting facts.
The first thing to answer is a question that worries many. And it sounds like this: “Is a whale a fish or a mammal?” The second option is correct.
The whale is a large marine mammal that is not related to porpoises or dolphins. Although they are included in the order Cetacea (cetaceans). In general, the names get a very interesting situation. Grinds and killer whales, for example, are considered whales. Although in accordance with the strict official classification they are dolphins, about which very few people know.
And it is better to trust a strict classification, because in ancient times Leviathans were called whales - sea many-headed monsters that could swallow the planet. In short, an entertaining story from the title.
Well, the answer above was given to the question “Is the whale a fish or a mammal?” 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 evolved 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 are superior to 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 hair 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. A 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 can 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 the breath) 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 is 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 by 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 20th century, uncontrolled hunting was discovered on these animals. By the middle of the last century, only 5,000 individuals remained in the world. People committed a terrible act, exterminating them. Emergency security measures were taken. Currently, 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 white whales have 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 fine, over time they get used to people, and even become attached to employees.
Their diet is varied. Belugas eat cod, flounder, herring, mollusks, seaweed, shrimp, lamprey, jellyfish, rib robes, pink salmon, goby, doggy, crayfish and many other marine creatures that can be eaten.
These creatures, like many others, also suffered because of human cruelty. Whalers easily drove them to the shallows, and the 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 representatives of cetaceans, and all in their own special and interesting. 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.