Mosquitoes are perhaps one of the most annoying and annoying insects on Earth. There is hardly anyone who loves them. In addition to the fact that they simply interfere with people’s lives, mosquitoes are also carriers of very dangerous diseases. Therefore, their destruction, on the one hand, is relevant, but on the other hand, it is unacceptable from a natural point of view, because even they have their place in the ecosystem.
The life of mosquitoes, like other insects, as well as animals and birds, is subject to a certain routine. Therefore, it is worth learning interesting facts about mosquitoes in order to better understand how they live, and whether it is possible for a person to live next to them in such a way that they cause him less discomfort. In addition, mosquitoes are indeed interesting in their own way, because they choose a mate based on certain characteristics, and they have reasons for this, they have certain preferences in places of residence, and also have some, almost incredible, abilities. From this article you will learn what a mosquito squeak really is and why mosquitoes need the blood of their victims.
In total, there are about 2500-3000 species of mosquitoes on our planet, and they are quite widespread. There are none except in Antarctica. In other territories, these insects feel quite at ease, which cannot be said about those who have to coexist with them.
Why don't males bite?
The mosquito's mouth is a kind of case formed by elongated lower and upper lips. It contains two pairs of jaws in the form of thin needles. Due to the underdevelopment of the jaws in males, the “male half” of the mosquito population does not bite, and the main dish on its “menu” is nectar.
The bite of a female mosquito occurs in a strictly determined order by nature - first, saliva is injected into the skin of the victim, which contains anticoagulants, due to which the blood does not clot or the process of clotting is slower. It is the saliva that provokes the appearance of redness, swelling and itching at the site of the bite, and in some people, a severe allergic reaction. In addition, saliva contains a substance that thins the victim’s blood and numbs the bite site.
Beginning of life
First you need to find out where mosquitoes come from. These small, ubiquitous insects emerge from eggs that females carefully lay on the surface of the water. The clutch immediately sinks to the bottom and after a few weeks the eggs turn into pupae, fully adapted to existence in an aquatic environment.
After some time, the small pupa completes the formation of all organs, after which it floats to the surface of the reservoir, the cocoon opens and an adult emerges from it.
When there is “no escape” from mosquitoes
The “biting” period for mosquitoes stops when the air temperature at night drops below +10 degrees. This acts as a signal for mosquitoes to hibernate or even die. Therefore, mosquitoes usually spend the winter hibernating, and some larvae generally feel great in a swamp or mud.
By the way, the activity time of mosquitoes may differ - the most “popular” time of day for this is, of course, twilight. But, for example, the Asian tiger mosquito bites at a completely different time - from 10 to 15 o'clock in the afternoon.
To find its victim, a mosquito cannot rely on its vision - it is quite poor, but the carbon dioxide exhaled by a person quickly shows it the “route” to the intended victim. Another “signpost” for mosquitoes is sweat appearing on a person’s skin - they bite sweaty people much more often.
Nutrition - who bites, why, whom and why
And who bites, a male mosquito or a female? Only females give us discomfort, regardless of what species they belong to. And they don’t care at all who they bite – a person or an animal. The main thing is that blood flows in the victim’s veins.
However, there are surprising features here too. Being notorious vampires, female mosquitoes are capable of becoming “vegetarians” for a while.
On a note! Vegetarianism is a necessary measure and females resort to it only in the absence of a source of blood for a long time!
What do mosquitoes eat besides blood? They exchange their protein menu for a carbohydrate one and feed on flower nectar, plant sap and pollen. By the way, for males this diet is lifelong and they feel great. But for females such food is not the most suitable, since during the period of vegetarianism they lose the ability to lay eggs.
On a note! Some types of mosquitoes do not feed on anything at all. For example, bell mosquitoes, which are easily recognized by the twitching of their legs when they sit. Such individuals do not live very long - their life expectancy is no more than a week, often only three days!
Having considered the features of the diet, it becomes clear why mosquitoes drink blood. The answer here is obvious - to live and be continuers of the family. Therefore, the cyclicity of egg laying will depend on the possibility of blood consumption. One mosquito clutch contains from 30 to 150 eggs, and the female produces offspring every two to three days!
Choice of victim
Why don't mosquitoes bite everyone? After all, it is known that these insects choose a victim for themselves, but on what basis? There are several assumptions.
- Blood group - these bloodsuckers are interested in the protein contained in the blood of a certain group, namely the first. Next in popularity are carriers of the third group, but the second is not so attractive for them.
On a note! The insect learns about the blood type by the signal that the person himself gives through his own skin, and about 85% of such people!
- The smell of carbon dioxide that a person exhales is attractive to the bloodsucker. And the more carbon dioxide the victim produces and the more often the victim breathes, the more likely the bloodsucker is to attack. And a mosquito senses it at a distance of 50 m!
On a note! For this reason, flying vampires bite children more often!
- Metabolism plays an important role in choosing a tasty morsel. The faster metabolic processes occur, the higher the temperature of the blood and the more intense the smell of uric and lactic acids, as well as ammonia and sweat, which are especially attractive to small bloodsuckers.
- Bacteria on the human body can also attract insects. At the same time, bloodsuckers will bite only in those areas where there are especially many of these bacteria concentrated, and places where they are completely absent are absolutely not attractive to bloodsuckers.
- The smell of alcohol can turn a person into an attractive object for this parasite. Ethanol not only attracts mosquitoes, but also increases body temperature and increases sweating, which, as we found out earlier, also attracts insects.
- Women during pregnancy are also at risk and, according to research, deserve the attention of blood-sucking insects twice as often. This is due to the fact that their body temperature is higher and they exhale 21% more carbon dioxide.
Why does a female need so much blood?
Females also feed on plant or fruit nectar, but without the protein in the blood, the eggs will not be able to develop normally. The meaning of life of a blood-sucking female is to search for a victim, directly suck blood, digest the blood with the subsequent maturation of eggs, and also search for a reservoir where she lays eggs. Everything is interconnected - therefore, without blood, eggs will not mature, so the “mosquito lady” is able to drink 5-7 times more blood than she weighs. The number of eggs laid varies from 300 to 350. Immediately after laying eggs, the female begins to look for new prey.
A mosquito flaps its wings 300 to 600 times per second
Here's a little secret. If you follow my recommendation, then mosquitoes will prefer your comrades who smear them all over themselves, mosquitoes, less fortunate brothers and frantically waving their arms - in addition to the corpses of their relatives, squeaky bloodsuckers react to the smell of sweat, flying to its source from the leeward side, sometimes from a distance of 3 km. Evening breezes, blowing from dry, elevated places preferred by people, to lowlands with reservoirs, where the main mosquito camp is located, help them smell sweaty people. The most intense flight of mosquitoes occurs from approximately 20 to 22 pm and from 4 to 6 am, plus or minus half an hour.
Mosquitoes sense the smell with their whiskers - special cilia are located there, but their taste buds are mainly on their legs. The mosquito's front legs sense the taste best - there are more sensitive hairs there than even on the proboscis. The middle ones are slightly less sensitive, while the hind ones are almost hairless, there are only a few taste hairs. Most clearly, a mosquito tastes sweat and blood, more precisely, the amino acids they contain - lysine, alanine, histidine - and lactic acid.
Male mosquitoes use their ears not only to smell, but also to hear. This was first discovered in 1878 by the American engineer Hiram Maxim, the same one, but then he was installing electric lights near the Grand Union Hotel in New York and noticed that crowds of mosquitoes were always swarming around the transformers. The engineer was not simple - not only did he determine that only males are interested in transformers (it’s easy to distinguish them by their fluffy hussar mustaches, mosquitoes have frail mustaches), and only when the transformer hums, but he also picked up a tuning fork and learned to command a swarm of mustachioed squeakers without transformer. The whiskered ones did not succumb to the magic of the tuning fork, and Hiram made the assumption that mosquitoes react to sound precisely with the help of their whiskers, which resonate with sound vibrations of a certain frequency, and the tuning fork and transformer simply sound at the frequency of the wings of female mosquitoes. The entomologists of that time laughed at the techie, and the editors of scientific journals considered it beneath their dignity to publish such primitive experiments and conclusions. Maxim was deeply offended and five years later he invented his famous machine gun, and another sixty-five years later, when epidemiologists began to closely study malaria carriers, his conclusions were exactly confirmed.
Later and more ingenious experiments revealed that the whiskers tremble in time with the wings of females only of their own species, and only sexually mature ones - young females squeak in a slightly different timbre. Mosquitoes of different species and ages flap their wings from 300 to 600 times per second, which is why their voice is thin (for comparison: a bumblebee - 123-233, a wasp - 165-274 flaps per second). The unsurpassed champions in this sense are mosquitoes, or bells - those non-aggressive ones that swarm in the air in swarms on clear evenings - and their opposite - biting midges, the filthiest component of midges, stuffed into any folds of clothing, into the nose and ears, preventing you from opening your eyes ... Both of them make up to 1000 strokes per second.
By the way, there is a sign that bells swarm in anticipation of rain. It apparently came from the arid steppe zone and is due to the fact that after swarming the female must find water in order to lay eggs, so in our area the sign does not work - there is usually plenty of water in the forest zone. After mating, but before laying eggs, it is advisable for the female to drink blood (but not necessarily - a mosquito that was not allowed to suck will also lay eggs, although their number will be noticeably smaller).
A mosquito's sucking device - a seemingly simple proboscis - consists of an upper lip, two upper jaws, two lower jaws, a subpharyngeal gland and a lower lip. All this together is several times the length of the head. The upper lip is folded into a tube through which blood flows into the pharynx. The tube cannot be inserted without elastic chitinous jaws, serrated at the front end. They are tightly but movably connected to the upper lip by the viscous fluid of the glands of the inner surface of the lower lip. The lower lip is a groove where, like in a case, the “sting” of a mosquito is inserted. It does not penetrate the wound, but, bending in the form of an arc, precisely directs the jaws to the blood vessels of the mosquito's victim, holds them together during blood sucking and, straightening, pulls them back after finishing the meal.
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- upper lip,
hch
- upper jaw,
g
- head,
ng
- lower lip,
nch
- lower jaw,
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- subpharyngeal,
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- antenna,
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- complex of piercing parts of the proboscis,
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- palp. Bottom right is the tip of the proboscis at 200x magnification.
The lower jaws, working alternately and wielding the teeth, actively penetrate the skin of the “donor”, leading with them the rest of the bundle - the upper lip, upper jaws and subpharynx. From the subpharynx - an unpaired outgrowth of the lower wall of the pharynx - saliva enters the wound, performing a dual function. First, it dilates the blood vessels around the bite site, thereby increasing blood flow. Secondly, it prevents blood from clotting so that it does not clog the tube of the upper lip. The specific pressure of a mosquito's proboscis on the skin exceeds that of a freight car on the rails. To reach it, the mosquito clings with its front legs - if they are torn off, it will not be able to pierce the skin.
If the mosquito is not disturbed, it will drink blood 5–7 times its own weight. Her abdomen swells, she barely flies up to find a secluded place to digest food. Only a tiny part of the food is used to maintain the life of the insect; the main part of the blood proteins turns into 120–350 eggs per week. Having laid eggs on the shore of a reservoir - certainly in the evening, after sunset - the female mosquitoes become vegetarians until the second mating. They almost never have a third marriage - the summer mosquito lives only for two months (if you're lucky). The eggs drift along the surface of the reservoir (or wait for rain on the shore - depending on the type of mosquito) for several days.
The larvae of biting mosquitoes usually hang in the water below the surface with their breathing tube exposed, and when in danger, they bend and go into the depths. In a reservoir rich in food, up to 4,000 larvae per liter of water accumulate - and this is the first great benefit of mosquitoes (and midges in general): the larvae of blood-sucking trash are an indispensable food for fish fry and other aquatic inhabitants. Some aquarists claim that fish fed by “devils” have an unusually bright color, which indicates their good health.
The larvae are hairy. Hairs are oars and at the same time sensitive receivers of external signals, and two lush tufts on the head are a device for feeding: the larva waves them at a speed of 200 strokes per minute, directing water with food to the mouth: the remains of plants and small animals, bacteria, protozoa, small algae, rotifers, spores and pollen. In addition, they can scrape food from aquatic plants. The larvae are heavier than water, but hang under the surface due to surface tension - like water striders, but on the other side of the film. The structure of mosquito larvae of different species is extremely ingenious and varied; they have a lot of incredible organs and adaptations for life, such as an anal pusher or a cover for the eyes.
After the fourth molt, the larva turns into a pupa. The doll is funny! She looks like a comma with horns and doesn't eat anything because she doesn't have a mouth. In the thick part of the transparent comma, the head and legs of the bloodsuckers are formed, even the eyes of future creatures are visible. Horns are respiratory tubes, the narrowed bases of which lead to the tracheal system. On the front of the abdomen a pair of tree-like hairs is visible, with the help of which the pupa is held against the surface film and perceives the slightest vibrations of the water surface. No matter how clumsy the doll may seem, it is nevertheless very agile. Disturbed, it dives deftly, wagging its belly, at the rear end of which there is a pair of leaf-shaped fin plates. Unlike the larva, the pupa is lighter than water - the cavities of the chest and the first segment of its abdomen are filled with air.
The mosquito takes 14-15 days to fully develop if the water temperature is not lower than +24°-+27°. Fecal sewage and leaks in water supply and heating systems in city basements are quite suitable in terms of temperature, but only for city mosquitoes that are accustomed to shit and chemicals - their larvae develop normally in such a cocktail, in which their forest brothers of the same species would be moved by horses in a few minutes . In recent years, with the advent of meters and HOAs, the basements in most houses have become drier - and mosquitoes in apartments have noticeably decreased.
Finally, the pupae straighten, burst at the back, and colorless, soft-bodied creatures crawl out of them. Their abdomen is filled with air - the insects swallowed it in advance so as not to drown. While the newborn mosquito sits on its fragile boat, biochemical processes are in full swing in its body; in a few minutes the covers become colored and harden. You can fly among people and, if the mosquito is a city, bring them reasonable, kind, eternal everything that he has absorbed from his youth, sitting in a canal. The bites of small city mosquitoes itch and hurt a lot, and the pimples in their place do not go away for a long time. Forest mosquitoes, although larger (they grew up in nature, did not get sick in childhood!), but bite more affectionately. In both cases, the main rule is not to scratch! It is advised to anoint with vodka, ammonia, garlic, onion juice, dandelion milk, soda solution, “Golden Star”, apply mashed bird cherry leaves, mint, citrus juice, cologne... and so on. The main thing is not to scratch.
In order for the onion and dandelion to show their full power, you need to pull out the pierced sting from the skin. Pulling out bees is easy, but extracting tiny mosquito proboscis is an undertaking for virtuosos, especially if you are in the tundra. In Evenkia, in five minutes, 400 mosquitoes land on a person’s forearm, 8,500 expectant mothers immediately bite into a deer, and sometimes up to five kilograms of gray bloodsuckers fly over each hectare. Creepy. But it depends on how you look. The biological cycle of substances in the cold tundra is lazy and slow. In just a few weeks, mosquitoes return to the watersheds the chemical elements that the water carried down, and this is the second great benefit of the midges. On tiny wings, from every hundred hectares of the swamp, two pounds of carbon, a pound of nitrogen, nine kilograms of phosphorus, six kilograms of calcium, and one and a half kilograms of silicon fly away annually. Microelements also travel: molybdenum, manganese, boron... In other words, food for plants has been flying to land from time immemorial.
Bird food also flies. It is for the sake of clouds of midges that every spring, swifts, swallows, flycatchers and many other migratory insectivorous birds fly thousands of kilometers to the north to feed their chicks - here is your third benefit. In one French park, so that mosquitoes would not bother vacationers so much, they placed containers with a special liquid, and there were no more mosquitoes. After a short time, a huge number of caterpillars and other pests appeared in the park, destroying the plantings. It turned out that mosquitoes attract insectivorous birds, which regulate the number of harmful insects. The ecological approach to solving problems in Europe is excellent; they did not take the path of using poisons and further escalating the useless struggle. They simply removed the barrels, and everything fell into place - mosquitoes began to fly, birds began to sing, and the caterpillars disappeared...
Mosquitoes have elegant shelters from birds - flowers. There, for the non-biting mosquito males and the mosquito maidens who have not tasted the blood, both a table and a warm shelter are ready. The flying army in the flower can keep warm because the concave shiny petals, like mirrors, direct the sun's rays to the pistil so that seeds set faster. Inside the flower it is several degrees warmer than outside. Having stained a flower with pollen, the enemy becomes an ally - it pollinates the plants. In the tundra and northern taiga, we must not forget about this - bumblebees and bees are sparse there. And this is the fourth benefit of vileness.
It would be possible, upon reflection, to find both a fifth and a sixth, but it is already clear that the total destruction of bloodsuckers will not lead to the improvement of the air, but to an ecological catastrophe. Nevertheless, it’s hard to call them friends. But you need to know the habits of your enemy and his weak points. So, mosquitoes stop attacking in the heat of +28°. Grace for them is +16° and relative air humidity of 80-90%. In dry air, whining squadrons will not last long - they lose water. The enemy also does not like high-altitude flights. This has long been used in malarial regions - they built eight-meter towers for overnight stays. I can’t explain why, but mosquitoes don’t bother me when spending the night in karst grottoes – and shallow ones at that; sometimes it’s enough just to be under a rocky canopy. Mosquitoes don’t like cedar phytoncides either... however, grottoes and cedar forests can’t be found everywhere.
As for personal protective equipment, modern repellents and insecticides are quite effective. If you find yourself in nature, without stocking up on anything in this sense, and the big-nosed ones are overwhelming you, search around in search of plants with a strong aroma such as mint, wormwood, celery, calamus, etc. By stretching the bun more firmly and rubbing the exposed parts of the body, you can feel calm for a while.
Original taken from newspape
What is the reason for the “patriotic feelings” of mosquitoes
The majority of mosquitoes live their entire lives near the places where they hatched and reached adulthood. But some mosquitoes have a special passion for travel - traveling up to 35 km in search of blood.
Yes, and mosquitoes prefer not to rise to heights - not only does the risk of being eaten by birds increase here, in addition, the higher, the colder it is, which means that the desire to bite will disappear, giving way to the need to hibernate. The maximum altitude for mosquitoes is 35 meters, so they are not found in the mountains, and residents of the upper floors of high-rise buildings note the absence of these insects in their homes.
The danger posed by mosquitoes
Despite the fact that mosquitoes are an important part of the ecosystem - they take part in pollinating plants, carrying almost all the elements of the periodic table on themselves, they are food for birds, frogs, fish and dragonflies, but at the same time they carry dangerous diseases, such as yellow fever, malaria, various types of encephalitis and others. To imagine the scale of the danger of these diseases, it is enough to say that malaria alone claims the lives of one to two million people every year.
How mosquitoes choose mates
Incredibly, mosquitoes value female beauty - they don’t hold “chubby” ones in high esteem. And the reason for this is banal: a female that is too plump will not be able to hang in the air for a long time during mating games. Although the overly thin “mosquitoes” are not of interest to the males, because they are simply blown away by the wind in the literal sense of the word. Actually, the wind, in general, is a big challenge for mosquitoes, because they weigh very little.
Mature females are most in demand among the opposite sex; they can be identified by the vibration of the air during a squeak. Having noticed any representative of the opposite sex, these insects adjust the flapping of their own wings to suit the potential “other half”. And what we usually mistake for the squeak of a mosquito is the noise that the insect’s wings make as a result of rapid flapping. A mosquito's wings beat about 600 times per second. The squeak made by females is much thinner than that of males, but even in females of different ages, it is different - old and young females squeak differently.
Having heard such a call, male mosquitoes distinguish which of the “ladies” makes it and decide on their choice.
During the mating process, male mosquitoes try to lure females after sunset by forming a swarm in front of them. “Ladies” prefer “gentlemen” in medium format.
Anatomy
The mosquito insect is distributed throughout the world, there are more than 3000 species, 38 genera. All have a similar structure, but differ in body size. They write a lot about mosquitoes in various sources; they study insects at school. The body structure is simple - head, chest, abdomen.
Head structure
The mouthparts of a mosquito deserve special attention. Includes upper, lower elongated lip, jaws. Inside the lips there is a groove with 12 needles. The jaws and tongue create a cavity for the passage of saliva.
Interesting!
One pair of long spines has projections called teeth. There are 50 of them in total. The insect tears the skin with its teeth. The next pair of needles acts as forceps and holds the wound open. The remaining needles hold the mosquito's proboscis and facilitate the flow of food. The long nose does not go completely under the skin, but reaches the blood vessels.
Female mosquitoes feed on blood. The insect injects saliva, which contains an anticoagulant that thins the blood. This prevents lymph from clotting and ensures a long supply of food. At one time, the female is capable of drinking about 5 ml of blood, with her own weight of 3 g; the number of bites depends on the behavior of the victim. The long nose of the male mosquito provides it with food from flower nectar and pollen.
The eyes are located on the sides of the head. Allows mosquitoes to see in infrared color. Thanks to this feature, insects determine the location of the prey by the outgoing heat. An infrared cloud forms around the body.
