The land is 71% covered with water. Fishes are the indigenous inhabitants of these aquatic expanses, which over billions of years of evolution have fully adapted to environmental conditions. They learned how to get oxygen from water, to hunt and find food, to live in various types of water bodies, to attack and disguise themselves.
At the moment, scientists know more than 35 thousand species of fish. But this is not the limit, because every year more and more species open up, surprising with their diversity. A whole branch of science, called ichthyology, is devoted to the study of these creatures. Today's rating is dedicated to the most interesting facts about fish.
10. New species are constantly appearing
Thanks to ichthyologists, mankind every year discovers for itself about five hundred inhabitants of rivers, lakes, seas and oceans. The great work that scientists do every year and every day is bearing fruit. Throughout the world, reports of the discovery of previously unknown species of fish appear.
For example, in Tasmania alone for 2018, a hundred new underwater inhabitants were entered in the directories. In addition to new ones, the list of existing ones is expanding. So, in the Gulf of Mexico, a new species of sharks was discovered, and in Japan a species of puffer fish was found.
9. Sizes from 7.9 mm to 20 m
In addition to variety, fish are able to surprise with their size. Everyone knows how huge can be the fierce predators of the seas - sharks. The largest individual reaches twenty meters. We know this giant as a whale shark., she likes to bask in tropical waters and poses no danger to humans. Only plankton enters its diet and is indifferent to human meat.
Despite its formidable size, it is quite a friendly fish and will even allow an impudent diver to ride 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 the vertebrate species came from fish.
Evolution is a very long, mysterious and complex process. Living things adapted to new living conditions, acquired, or lost their abilities. It is known that more than half of the vertebrate species came from fish. Most likely, this happened in Paleozoic, which began 541 million years ago. This era lasted nearly 300 million years.
The fish learned to “walk” even on the seabed, under water, and, having come to land, only continued the long evolutionary path.
7. Three types of breeding
Reproduction is common to all living things on the planet. The simplest formulation of this complex process is to reproduce your own kind. Typically, a species has one particular type of breeding. But the fish surprise us in this, having three different types of self-reproduction..
The first, familiar to us type is bisexual reproduction. With him, it is easy to determine who is male and who is female. The roles are clearly distributed, each gender performs only its reproductive functions.
The second type is hermaphroditism. In this case, things that are more surprising for us occur and the sex of the individual changes throughout life. Having been born, for example, as a male, a fish, at a certain age, is reconstructed and further lives and functions as an absolutely full-fledged female.
The third type is called gynogenesis. This is a process in which the sperm performs only the function of starting the reproductive system, and is not a prerequisite for reproduction.
6. Some fish can change sex
Pisces do not require surgery to change sex. Some species have a special structure of the body, in which their sex changes throughout life.. Such a system prevails, for example, in sea bass and guban.
5. Seahorse - the only fish that swims vertically
Skates are small sea fish whose genus totals up to 57 species. Seahorses got their unusual name due to their resemblance to a chess piece. Fans of warm water live in the tropics and are afraid of cold water, which can destroy them.
But their most remarkable feature is that they do not move like everyone else. If all fish swim strictly horizontally, then seahorses stand out from the total mass, moving exclusively vertically.
4. Patti - eel long-lived, age 88 years
Another amazing fish that looks very much like a snake is called European eel. This serpentine fish is even able to cover short distances by land.
For a long time, eel was considered a representative of viviparous fish due to the inability to find fry and the place of spawning. 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 the time of capture was three years. This living exhibit was even given a very sweet name - Patti. The most amazing thing in his biography is that he died only in 1948, becoming the longest-living fish, having lived as much as 88 years.
3. The sailboat floats at a speed of up to 100 km / h
A fish with the beautiful name Sailboat lives in the tropical and temperate waters of all the oceans on Earth. It got its name thanks to 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 has a weight of up to one hundred kilograms. Fish is a true speed record, gaining up to a hundred kilometers per hour. The streamlining of the body helps to achieve such high values, along with the fin retractable in the back and vigorous tail movements.
2. Piranha - the most dangerous fish
Fish, terrifying many people and becoming the hero of horror films and thrillers. Piranha is rightfully considered the most dangerous fish that lives on Earth.. The name comes from the Indian language and literally translates as a sawfish. These monsters have more than 50 species, but all live only in the waters of South America.
Exactly imitating sharks, piranhas are able to feel the blood in the water. even if it is just a drop at a great distance from them. The powerful jaws of these monsters are able to tear out pieces of meat from the victim, and a flock of such fish will tear cattle in minutes. But individually, the fish are very shy and can lose consciousness from loud and sudden noise.
1. One of the earliest symbols of Christianity
One of the earliest symbols of Christianity was the familiar fish.. The fact is that in translation from the ancient Greek language the fish sounds like Ichthys what is the abbreviation. Ichthys stands for phrase, an approximate translation of which means “Jesus Christ the Son of God the Savior”.
The appearance of such a mysterious message is associated with the persecution of the early Christians by the Romans. The laws of that time prohibited the propaganda of Christianity, the open practice of this religion, the creation and wearing of symbols, which indicated belonging to the faith.
The image of the fish was a secret sign indicating a person’s religion. The symbol was applied to clothing, body and homes, and was also depicted in caves where secret services took place.
Fish often appears in scripture and in many parables. The most famous fish-related story tells how one fish ate a huge number of hungry people. Christians were also compared with fish in that era, which followed the course of faith in the waters of eternal life.