Any person who has visited the warm seaside has probably come across jellyfish (although some jellyfish are found in fresh water). In these creatures, 95% composed of water, there is little pleasant. With direct contact, they are as harmless as possible, although a simple touch to the jelly-like body of a jellyfish is hardly capable of evoking positive emotions. If you are unlucky, then a meeting with a jellyfish can end with burns of varying severity. There are fatalities, but fortunately they are extremely rare. So it is more pleasant to communicate with jellyfish through glass or a monitor.
1. If we approach the classification of living organisms strictly, then separate animals with the name “Medusa” do not exist. This word in biology is called the interval of life of stinging cells - animals, 11 thousand species of which are united by the presence of stinging cells. These cells, secreting substances of varying degrees of toxicity, help the escapes to hunt and fight off enemies. Jellyfish appear in eaters after a generation. First, polyps are born, then jellyfish are formed from them. That is, jellyfish are not born from jellyfish, therefore they are not considered separate species.
2. If you enter the names of representatives of the animal world into the Yandex search engine, in the first lines of the issue you can almost always find a link to the Wikipedia page dedicated to this animal. Medusa did not receive such an honor. There is a link to the Meduza page, but this page is dedicated to a Russian-language opposition site based in Latvia.
3. Stinging cells of jellyfish are, depending on the mechanism of action, of three types: sticking, piercing, and loop-like. Regardless of the mechanism, they eject their weapons at great speed and in a very short time. The overload experienced by the stinging thread at the time of the attack sometimes exceeds 5 million g. The piercing stinging cells act on the enemy or prey with a poison, which is usually extremely selective. Gluing cells catch small prey, sticking to it, and loop-like cells cover future food at an incredible speed.
4. Those stinging cells of jellyfish that use poison as a means of destruction can be considered the most effective weapon. Even a conditionally extremely weak (from the point of view of a person) cell is capable of killing a creature hundreds of thousands of times larger in mass. The most dangerous for humans are box jellyfish. A jellyfish called the sea wasp lives off the northern coasts of Australia and the adjacent islands of Indonesia. Its poison is guaranteed to kill a person in 3 minutes. The substance secreted by the stinging cells of the sea wasp simultaneously acts on the heart, skin and nervous system of a person. In northern Australia, first aid kits on rescue ships are equipped with an antidote for sea wasp bites, but often rescuers simply do not have time to apply the drug. It is believed that at least one person per year is killed by sea wasp bites. As a countermeasure to sea wasps, tens of kilometers of net fences are being installed on the beaches of Australia.
5. American swimmer Diana Nyad for 35 years, starting in 1978, tried to swim the distance between Cuba and the US coast. The brave sportswoman made five attempts to overcome the record distance of 170 km. Contrary to expectations, the main obstacle was not the sharks that simply swarm the waters of the Gulf of Mexico. Nayyad interrupted her swim twice because of jellyfish. In September 2011, a single burn from contact with a large jellyfish, which was not noticed by the people accompanying the swimmer, forced Diana to stop the swim. She already had 124 kilometers behind her. In August 2012, Nayyad met a whole flock of jellyfish, received 9 burns, and retired only a couple of tens of kilometers from the US coast. And only the swim, which took place on August 31 - September 2, 2013, could not be interrupted by the jellyfish.
6. The toxicity of jellyfish has long been used in scientific research. The poisons secreted by stinging cells are highly selective. They usually (although there are exceptions) have a striking power corresponding to the size of a typical victim. Therefore, on the basis of studies of stinging cells and the composition of poisons, drugs can be made.
7. Israeli startup "Cine'al" plans to start a large-scale production of feminine sanitary pads and diapers. Jellyfish will be the raw material for the startup's products. The idea, which seems to lie on the surface, that since jellyfish are 95% water, their connective tissues should be an excellent adsorbent, was first put forward by Shahar Richter. A Tel Aviv University employee and colleagues developed a material they called "Hydromash". To obtain it, the dehydrated jellyfish meat is decomposed, and nanoparticles that can destroy bacteria are added to the resulting mass. The mixture is processed into a durable but flexible material that absorbs a large amount of liquid. Pads and diapers will be made of this material. This method will make it possible to annually dispose of thousands of tons of jellyfish, annoying vacationers and power engineers. In addition, Gidromash completely decomposes in just a month.
8. A jellyfish can have many tentacles, but there is only one hole in the dome (the exception is the Blue Jellyfish - this species has an oral hole at the end of each of dozens of tentacles). It serves both for nutrition, and for the removal of waste products from the body, and for mating. Moreover, in the process of mating, some jellyfish perform a kind of dance, during which they intertwine the tentacles, and the male gradually pulls the female towards him.
9. The remarkable writer Sir Arthur Conan-Doyle is known, in addition to his skill, also for the fact that he allowed many blunders, like hearing snakes, in the descriptions of representatives of the animal world. This does not detract from the merits of his works. Rather, even some absurdities make the works of Conan Doyle even more interesting. So, in the story "The Lion's Mane" Sherlock Holmes uncovers the murder of two people, committed by a jellyfish called Hairy Cyanea. The burns inflicted on the deceased by this jellyfish looked like the marks from the blows of the whip. Holmes, with the help of other heroes of the story, killed cyanea by throwing a piece of rock on her. In fact, Hairy Cyanea, which is the largest jellyfish, despite its size (a cap up to 2.5 meters in diameter, tentacles over 30 meters in length) is not capable of killing a person. Its poison, designed to kill plankton and jellyfish, causes only a slight burning sensation in humans. Hairy Cyanea poses some danger only for allergy sufferers.
10. Medusa Turritopsis nutricula from the point of view of human ideas about life can be considered immortal, although scientists avoid such big words. These jellyfish live mainly in tropical seas. After reaching puberty and several mating cycles, the rest of the jellyfish die. Turrotopsis, after mating, return back to the state of a polyp. From this polyp jellyfish grow, that is, the life of the same jellyfish continues in a different hypostasis.
11. Back in the second half of the 19th century, the Black Sea was famous for its abundance of fish. It was actively caught by fishermen of all coastal countries without any particular desire for the safety of species. But in the second half of the twentieth century, stocks of fish, primarily small predators such as anchovy and sprat, began to melt before our eyes. Where entire fleets used to fish, the catch was left only for single vessels. According to a developed habit, the reduction in fish stock was attributed to a person who polluted the Black Sea, and then, in a predatory manner, caught all the fish out of it. Lonely prudent voices drowned in demands to limit, prohibit, and punish. In an amicable way, there was nothing much to limit - the fishermen left for more favorable areas. But the stock of delicious anchovies and sprats has not recovered. Upon deeper study of the problem, it turned out that the fish were replaced by jellyfish. More precisely, one of their types is Mnemiopsis. These jellyfish were not found in the Black Sea. Most likely, they got into it in the cooling systems and ballast compartments of ships and ships. The conditions turned out to be suitable, there was enough food, and the Mnemiopsis pressed the fish. Now scientists only argue about how exactly this happened: whether jellyfish eat anchovy eggs, or they absorb their food. Of course, the hypothesis that the Black Sea has become too favorable for jellyfish in the context of global climate change was bound to appear.
12. The eyes as separate organs in the generally accepted biological understanding do not have jellyfish. However, visual analyzers are available. There are growths along the edges of the dome. They are transparent. Under them is a lens-lens, and even deeper is a layer of light-sensitive cells. It is unlikely that jellyfish will be able to read, but they can easily distinguish between light and shadow. Roughly the same applies to the vestibular apparatus. Jellyfish do not have ears in general and inner ears, but they have a primitive organ of balance. The most similar analogue is an air bubble in a liquid in a building level. In a jellyfish, a similar small cavity is filled with air, in which a tiny lime ball moves, pressing on the nerve endings.
13. Jellyfish are gradually taking over the entire World Ocean. While their number in water around the globe is uncritical, however, the first calls have already sounded. Most of all jellyfish cause troubles to power engineers. In the coastal states, power plants are preferred to be located near the coast in order to use free sea water for cooling power units. The Japanese, as you know, came up with the idea after Chernobyl to put even nuclear power plants on the shores. Water is drawn into the cooling circuits under high pressure. Together with it, jellyfish fall into the pipes. Protective nets that protect the systems from getting large objects into them are powerless against jellyfish - jelly-like bodies of jellyfish are torn and absorbed in parts. Clogged cooling systems can only be cleaned manually, and it takes a lot of time and money. It has not yet come to incidents at nuclear power plants, but in December 1999, for example, there was an emergency power outage on the Philippine island of Luzon. Given the time of the incident (many were waiting for the end of the world) and the location (the political situation in the Philippines is far from stable), it is easy to assess the extent of the panic that has erupted. But in fact, it was jellyfish that clogged the cooling system of the largest substation in the country. Problems with jellyfish were also reported by power engineers from Japan, the United States, Israel and Sweden.
14. In Burma, Indonesia, China, Japan, Thailand, the Philippines and a number of other Asian countries, jellyfish are eaten and even considered a delicacy. Hundreds of thousands of tons of jellyfish are caught annually in these countries. Moreover, there are even farms in China that specialize in the cultivation of “food” jellyfish. Basically jellyfish - domes with separated tentacles - are dried, dried and pickled, that is, the processing processes are similar to our manipulations with mushrooms. Salads, noodles, ice cream and even caramel are made from jellyfish. The Japanese eat jellyfish naturally by wrapping them in bamboo leaves. Theoretically, jellyfish are considered very useful for the body - they contain a lot of iodine and trace elements. However, it should be borne in mind that each jellyfish daily “filters” several tons of sea water. With the current purity of the World Ocean, this can hardly be considered an advantage. Nevertheless, Lisa-Ann Gershwin, author of the acclaimed book "Stung: On the Blossom of Jellyfish and the Future of the Ocean", believes that humanity can save the oceans from jellyfish only if it begins to actively consume them.
15. Jellyfish flew into space. Dr. Dorothy Spangenberg, from the American University of East Virginia, apparently has a low opinion of her fellow species. In order to presumably investigate the effect of gravity on the organisms of people born in space, Dr. Spangenberg for some reason chose jellyfish - creatures without a heart, brain and central nervous system. NASA's leadership went to meet her, and in 1991 about 3,000 jellyfish went into space on the reusable spacecraft Columbia. Jellyfish survived the flight perfectly - about 20 times more of them returned to Earth. The offspring were distinguished by a property that Spangenberg called the pulsation anomaly. Simply put, space jellyfish did not know how to navigate in space using gravity.
16. The bulk of jellyfish species swim with tentacles down. Of the large species, only Cassiopeia Andromeda is an exception. This very beautiful jellyfish lives only above the coral reefs in the Red Sea. Outwardly, it does not resemble a jellyfish, but a fantastic underwater garden located on a round platform.
17. Most of the French probably would not mind if the frigate called "Medusa" never existed, or at least never remembered about it. A painfully ugly story is connected with Meduza. This ship, following in the summer of 1816 from France to Senegal, carried the officials of the colonial administration, soldiers and settlers. On July 2, Meduza ran aground 50 kilometers off the coast of Africa. It was not possible to remove the vessel from the shallows, it began to collapse under the blows of the waves, provoking panic. The crew and the passenger built a monstrous raft, on which they forgot to take at least a compass. The raft was to be pulled by boats, in which, of course, naval officers and officials sat. The raft was towed for a short time - at the first sign of a storm, the commanders abandoned their charges, cut the towing ropes and calmly reached the shore. Real hell broke loose on the raft. With the onset of darkness, an orgy of murders, suicides and cannibalism began. In just a few hours, 150 people turned into bloodthirsty animals. They killed each other with weapons, pushed each other off the raft into the water and fought for a place closer to the center. The tragedy lasted 8 days and ended with the victory of a close-knit group of 15 people who remained on the raft. They were picked up after another 4 days. Five “kings of the mountain” died allegedly from “unaccustomed food” on their way to France. Out of 240 people, 60 survived, most of the survivors are escaped officers and officials. So the word "Medusa" became for the French synonymous with the concept of "terrible tragedy."
18. There is a Jellyfish Museum in Kiev. It opened quite recently and fits in three small rooms. It would be more correct to call the exposition an exhibition - it is just a set of about 30 aquariums with small explanatory plates. But if the cognitive component of the museum limps, then aesthetically everything looks great. Blue or pinkish lighting helps you see the smallest details of jellyfish and matches their smooth undulating movements very well. Tastefully selected music sounds in the halls, and it seems that jellyfish are dancing to it. There are no very rare or very large species on display, but there are enough jellyfish available to get an idea of the diversity of these creatures.
19. The movements of jellyfish are extremely rational. Their external slowness is due solely to the resistance of the environment and the fragility of the jellyfish themselves. Moving, jellyfish consume very little energy. This rationality, as well as the structure of the jellyfish's body, gave Dr. Lee Ristrof from New York University the idea to create an unusual flying machine.Outwardly, the flying robot looks little like a jellyfish - it is a structure of four wings with a small engine and simple counterweights - but it keeps it in balance just like a jellyfish. The importance of this flying prototype is that the "flying jellyfish" does not need expensive, relatively heavy and energy-consuming flight stabilization systems.
20. Jellyfish are sleeping. This statement may seem like the height of absurdity, because it is believed that only animals with higher nervous activity sleep. However, students at the California Institute of Technology, noticing that sometimes jellyfish react differently to the same touch, decided to check whether these creatures are sleeping. For experiments, the already mentioned Cassiopeia Andromeda was used. This jellyfish periodically throws waste products out of the body. This kind of pulsation had a frequency of 60 emissions during the day. At night, the frequency dropped to 39 pulsations. At the second stage of research, jellyfish were quickly raised from the depths almost to the surface. While awake, the jellyfish reacted almost instantly, plunging back into the water column. At night, they needed some time to start diving back. And if they were not allowed to sleep at night, the jellyfish reacted sluggishly to touch for the next day.
