top 10 of the most informative about the inhabitants of the sea and rivers

The earth is 71% covered with water. Fish are the native inhabitants of these bodies of water, which over billions of years of evolution have fully adapted to the environmental conditions. They learned to draw oxygen from water, to hunt and find food, to live in various types of water bodies, to attack and disguise themselves.

Currently, scientists know more than 35,000 species of fish. But this is not the limit, because every year more and more new species are discovered, surprising in their diversity. A whole branch of science called ichthyology is devoted to the study of these creatures. Today’s note is devoted to the most interesting facts about fish.

10. New species are constantly appearing

Thanks to ichthyologists, mankind annually discovers about five hundred inhabitants of rivers, lakes, seas and oceans.. The excellent work that scientists do every year and every day is paying off. All over the world there are reports of the discovery of previously unknown species of fish.

For example, in Tasmania alone, in 2018, one hundred new underwater inhabitants were listed in the directories. In addition to the new ones, the list of existing ones is also growing. Thus, a new species of shark was discovered in the Gulf of Mexico and a variety of puffer fish was found in Japan.

9. Sizes from 7.9mm to 20m

In addition to diversity, fish are able to surprise with their size. Everyone knows how huge the ferocious predators of the seas – sharks – can be. The largest individual reaches twenty meters. We know this giant as the whale shark., she loves to bask in tropical waters and poses no danger to humans. Its diet includes only plankton and it is indifferent to human meat.

Despite its fearsome size, it is quite a friendly fish and will allow even an impudent diver to climb on its back.

The smallest fish, whose body has a modest size of 7.9 mm in length, lives in Indonesia.

8. More than half of vertebrate species are descended from fish

Evolution is a very long, mysterious and complex process. Living beings adapted to new living conditions, capacities acquired or lost. It is known that more than half of vertebrate species are descended from fish. Most likely, this happened in the Paleozoic, which began 541 million years ago. This era lasted nearly 300 million years.

Fish learned to “walk” on the seabed, under water, and having come out on land, they only went on a long evolutionary path.

7. Three types of breeding

Reproduction is characteristic of all living beings on the planet. The simplest formulation of this complex process is the reproduction of its own species. Usually a species has a specific type of reproduction. But fish also surprise us in this, having three different types of self-reproduction..

The first type, which is familiar to us, is bisexual reproduction. With him, it is easy to determine who is a man and who is a woman. The roles are clearly distributed, each sex exercises only its reproductive functions.

The second type is hermaphroditism. In this case, more surprising things happen to us and the sex of the individual changes over the course of life. Being born, for example, as a male, a fish, at a certain age, rebuilds itself, and then lives and functions as a full-fledged female.

The third type is called gynogenesis. This is a process in which the sperm only performs the function of starting the reproductive system and is not a prerequisite for reproduction.

6. Some fish can change sex

Pisces doesn’t need sex change surgery. Some species have a particular body structure in which their sex changes throughout life.. Such a system prevails, for example, in groupers and wrasse.

5. The seahorse is the only fish that swims vertically

Rays are small marine fish, the genus of which includes up to 57 species. Seahorses got their unusual name because of the resemblance to a chess piece. Hot water lovers live in the tropics and are afraid of cold water, which can kill them.

But their most remarkable feature is that they don’t move like everyone else. If all fish swim strictly horizontally, seahorses stand out from the total mass, moving exclusively vertically..

4. Patti is a long-lived, 88-year-old eel

Another amazing fish that looks a lot like a snake is called the European eel. This snake-like fish is even able to travel short distances on land.

For a long time, the eel was considered a representative of viviparous fish due to the inability to find fry and spawning grounds. One of the representatives of this species was caught in 1860 in the Sargasso Sea and placed in a museum aquarium in Sweden. The approximate age at capture was three years. This living exhibit even got a very cute name – Patty. The most surprising thing about his biography is that he did not die until 1948, becoming longest-lived fish, living up to 88 years.

3. The sailboat sails at speeds of up to 100 km/h

A fish with a beautiful sailfish name lives in tropical and temperate waters of all oceans existing on Earth. It takes its name from the dorsal fin, very similar to the sail of a ship. The fin can be twice as high as the fish itself.

The sailboat reaches three meters in length and weighs up to one hundred kilograms. The fish is a real speed record holder, gaining up to one hundred kilometers per hour. The streamlining of the body, combined with a retractable fin and vigorous tail movements, helps to achieve such high values.

2. Piranha is the most dangerous fish

A fish that terrifies many people and became the hero of horror films and thrillers. Piranha is rightly considered the most dangerous fish that lives on Earth.. The name comes from the Indian language and literally translates to sawfish. These monsters have more than 50 varieties, but all of them live only in the waters of South America.

Exactly mimicking sharks, piranhas are able to smell blood in the water. even if it is only a drop at a great distance from them. The powerful jaws of these monsters are able to tear off pieces of meat from the victim, and a flock of such fish tears livestock in minutes. But alone, fish are very shy and can lose consciousness from a sudden loud noise.

1. One of the first symbols of Christianity

One of the first symbols of Christianity was the familiar fish.. The fact is that, translated from the ancient Greek language, the fish looks like “ichthys”, which is an abbreviation. “Ichthys” is deciphered as a phrase whose rough translation means “Jesus Christ God Son Savior“.

The appearance of such a mysterious message is associated with the persecution of the first Christians by the Romans. The laws of the time prohibited the promotion of Christianity, the open practice of this religion, the creation and the wearing of symbols indicating membership in the faith.

The image of a fish was a secret sign indicating a person’s religion. The symbol was applied to clothing, body and dwellings, and was also depicted in caves where secret services took place.

The fish appears often in the scriptures and in many parables. The most famous story related to fish tells how a large number of hungry people ate a fish. At that time, Christians were also compared to fish, which followed the stream of faith into the waters of eternal life.

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