Dolphins are the most intellectual and smart of all animals living on Earth. And whales are just the largest animals. Both those and others, although they retained similarity with other marine inhabitants, but still differ significantly from them.
And in fact they are not fish, although they can demonstrate all the signs of fish: the presence of fins, existence in the aquatic environment, and externally resemble fish. And here a logical question arises why and how these animals returned to the water world and where their ancestors came from?
Who are the ancestors of whales and dolphins?
For a long time, scientists studied these animals in order to find their predecessors. In the end, the version was put forward that the ancestors of whales and dolphins existed at least 50 million years ago-and existed on Earth. The general opinion that predators forced them to leave in the ocean, because of which the new environment had to conquer.
10 years ago in India, the remains of one of the ancestors of the whales, who received the name Indochius, were discovered in India. This animal was most likely ordinary herbivore and even paired cake. The hooves with the development of a new habitat fell off, and for only 20 million, Indochius learned to see his ears where did the ability of whales and dolphins come from to echolocation.
Whales and dolphins mammals?
Now no one disputes the statement that both dolphins and whales are mammals. They give birth to live offspring and feed it with milk. And the similarity with the fish is everywhere explained to the way of life in the same environment with them.
However, not so long ago, scientists believed that Kit is just a huge fish. And even Karl Linnaeus is a wellknown naturalist in his first book called “Nature System” boldly says that fish whales only after many years this mistake was corrected by him. So the whales continued to be attributed to fish until recently until the end of the 19th century.
With all this, both dolphins and whales are not able to breathe in water and they periodically need to come to the surface behind oxygen. And unlike fish, they have high body temperature, characteristic of mammals. Well, a significant supply of fat perfectly protects these types from hypothermia.
An interesting fact: although these animals feed the kids with milk, their cubs are deprived of their lips therefore, parents are forced to literally inject milk into the mouth of babies as necessary.
Dolphins and whales breathe very peculiarly, which is unusual for mammals: they have this process through a special organ the breath located on the head in its upper part. Together with the air, they exhale a powerful stream of water and thanks to this, many tourists can enjoy an amazing sight: a fountain tearing from the head of the animal.
Difference and similarity with fish
Despite the fact that dolphins and whales were considered fish for a long time, they are still different from these water inhabitants. These animals belong to marine mammals like cats, seals and sperm whalers.
Way of breathing, lack of gills, the need to breathe air, the birth of living babies instead of throwing caviar, and, most importantly, a warm body distinguishes them from fish.
These animals acquired their similarities with fish many millions of years ago, when many ancestors of all marine inhabitants existed not in water, but on land many scientists are of this opinion. And therefore, many of the marine animals are able to breathe, give birth to living offspring, take care of children and create couples in a word, behave as normal mammals do.
But you need to understand that the ancestors of such animals ate and fed precisely in the water t.e. Their food diet was provided by the seas and oceans, for which they urgently had to learn how to swim and survive in an unusual environment.
Naturally, over time, many of such animals finally decided to leave the land and turn into marine mammals. And already in the water they polished their appearance in order to be able to calmly exist in the aquatic environment. In this way, dolphins and whales found their modern appearance and began to resemble fish.
There are not only fish in the ocean
In fact, whales and dolphins are not the only mammals who live in the marine environment. There, seals, sea cats, killer whales and many more animals that differ significantly from fish feel great there.
All these animals completely do not have gills, but such a respiratory organ as the lungs functions perfectly. They are able to gain a huge amount of air on the surface and slowly use it in the water element.
Such animals differ in the method of childbearing none of them lay off either eggs or caviar and they all produce living cubs. Moreover, they also feed them exclusively as mammals it is milk.
Another main and significant difference of such animals from fish is their intellect and mental abilities. No wonder they say that dolphins are endowed with them highly and so that in India they are even recognized as separate whole personalities at the legislative level. By the level of development of dolphins in India, they put on one bar with a person.
Unlike fish that exist to preserve their life, food and elementary sleep, dolphins spend a lot of time on social communication and other interaction with their relatives. And this is not to mention the fact that their brain is much more complicated and is more in volume than that of fish.
The features of dolphins and whales are manifested even in their dreams these mammals are not able to plunge into sleep. This is due to their respiratory system the animal brain is always forced to wake up in order to be able to emerge to the surface if necessary. Therefore, they sleep only with one closed eye.
In addition to breathing, such a sensitive dream is also associated with the fact that during sleep the temperature of the bodies is significantly reduced and the animal can simply freeze.