"Mosquito circle"?
In the early morning or dusk of summer, have you ever encountered a group of "mosquitoes" hovering overhead? Although they did not frantically swoop down and suck your blood, the picture of black pressure is still very frightening, and it is easy to make you have self-doubt, doubting whether you have not washed your hair for half a month, and have a smell on your body, which is particularly embarrassing... Therefore, you silently added another "felony" to the mosquito that was already "heinous" in your heart.
Although I also hate mosquitoes, this time I still have to say a fair word: "You have wronged mosquitoes!" "Because, hovering over your head is not a mosquito, but a kind of insect called an insect, although it has the word 'mosquito' in its name and looks very similar to a mosquito, but they are not very close." Shaking mosquitoes are belonging to the diptera "longhorn suborder" under the general family of shaking mosquitoes, and mosquitoes are belonging to the diptera "longhorn suborder" under the general family of mosquitoes, let's take a closer look at this mosquito "back black pot" organism - shaking mosquito.
Close-up of the shaking mosquito (source network)
<h1 class="pgc-h-arrow-right" > shake mosquito is not a mosquito</h1>
Let's first distinguish between rocking mosquitoes and mosquitoes, whose lives are divided into four periods: eggs, larvae, pupae, and adults. In each growth period, the shaking mosquitoes and mosquitoes are very small or large, and we will take a closer look at the difference between the shaking mosquitoes and mosquitoes
Egg period
The eggs of the mosquitoes are laid directly on the surface of the water, in the form of long gelatinous bands or blocks, and contain dozens to hundreds of eggs. The eggs are usually spherical or oblong-oval in color, with white, yellow, brown, or red colors. After 3-7 days of floating, the eggs hatch.
Mosquitoes, like mosquitoes, lay mosquito eggs directly on the surface of the water, but depending on the species, mosquito eggs will appear in the form of single eggs or integrated eggs. For example, the eggs of Anopheles mosquitoes are yielded alone, and one grain is not gathered together. The eggs of Culex mosquitoes will be gathered together in numbers of hundreds. There are also several colors of mosquito eggs, common ones are white, black and so on. Similarly, after 3-7 days of pontoon, mosquito eggs hatch.
Larval stage
It is a little difficult to identify whether it is the eggs of the mosquitoes or the eggs of the mosquitoes, but the mosquitoes and mosquitoes in the larval stage are very easy to identify, the body of the mosquitoes is red and is also called the blood red worm, and the dark brown body of the mosquito larvae is also called jié jué, which can be seen in the following figure.
Larval comparison
In addition to the color, the lifestyle of the mosquito larvae and the mosquito larvae is also very different, the hatched hemoglobin worm will turn into a benthic life after 3 to 6 days of floating life, the first thing to do is to "build a house", it will use the fine sand under the water, algae, decay, silt and salivary glands secreted filaments to build a two-headed open tube nest for itself, and then feed on bacteria, algae, aquatic plants and small animals, I believe many people have seen them in the muddy ditch in the countryside.
Algae-eating mosquito larvae
Compared with the mosquito larvae that need to be diligent and earnest to "build a house", the mosquito larvae are very relaxed, living a "clothes to reach out and eat to open their mouths" days. Every day, the widow only needs to use the tail to cling to the water surface and hang upside down in the water. The bristles at its mouth create a stream of water that allows organic matter and microorganisms to flow into its stomach.
Although mosquitoes and mosquitoes have different lifestyles during the larval stages, the experiences are extremely similar, and they all need to undergo four molts during the larval stage before they develop into pupae.
Pupal period
During the pupal period, the pupae of mosquitoes looks like a "comma" and is less able to distinguish between male and female. The pupae of the mosquito can be judged by the naked eye, and the pupae of the male mosquito are generally short and thin, while the female is generally long and wide.
On the other hand, the pupae of both have an interesting characteristic, that is, they can move, although they cannot eat, but the pupae of mosquitoes and mosquitoes will swim around like small tadpoles. After a pupal period of a few hours or days, feathering begins.
Period of shaking mosquitoes and mosquito pupae
Adult stage
Feathering is the last metamorphosis of their lives, and they break out of their shells to become adults. Adult mosquitoes and shake mosquitoes believe that many people are 'stupid and can't tell the difference', I summarized 4 identification methods for everyone:
Shake the mosquito feather
Method one, look at the antennae: the antennae of adult mosquitoes are very developed, and the male antennae are feathery, so if you see a 'mosquito' with feathery antennae, it is definitely a mosquito. However, this method has a disadvantage, it can not distinguish between female mosquitoes and mosquitoes, because the antennae of female mosquitoes are the same as those of mosquitoes, like ordinary hair.
Method two, mouthpiece: This can be said to be the most obvious difference between shaking mosquitoes and mosquitoes, shaking mosquitoes are "vegetarians" who do not suck blood, and adult insects usually feed on plants or plant pollen. So the shake mosquito does not have a mouthpiece like a mosquito. Mosquitoes, on the other hand, have long mouthpieces with precise construction, so they can still be seen if you look closely.
Mouthpiece contrast, shake mosquito (left), mosquito (right)
Method three, look at the body size: the shape of the mosquito will be slightly larger, lighter color, usually cyan or brown, and do not have white spots on the body like many mosquito species. The abdomen of the mosquito is more slender, generally exceeding the length of the wings, and the forefoot of some species will be cocked when resting.
Method four, look at the wings: Entomologists will also look at the difference in the wing veins of their wings when distinguishing between mosquitoes and mosquitoes. The wings of mosquitoes, especially the wing veins, are attached to thicker bristles, while the wings of the mosquitoes are relatively clean, especially the less concentrated bristles in the wing veins. But these need to be seen with the help of a magnifying glass, or even a microscope.
Contrast of shaking mosquitoes and mosquito wings
<h1 class = "pgc-h-arrow-right" > why the mosquito hovers over the head of a human</h1>
After understanding the difference between mosquitoes and rocking mosquitoes, let's find out another thing, that is, since mosquitoes do not suck blood, why do they still hover in groups above our human heads? And what the hell are they doing on our heads?
Formation of mosquito coils
First of all, the mosquito is born with the same interest in carbon dioxide as the mosquito, which leads to the mosquito being easily attracted to the carbon dioxide produced by humans. Everyone's physique is different, and the concentration of carbon dioxide produced is also different, so we often encounter pedestrians walking in the same park, some of whom have swaggering mosquitoes on their heads and some who do not have them on their heads.
Second, when some mosquitoes smell carbon dioxide coming to your head, they will begin to secrete a substance called pheromones. This substance is an in vitro pheromone, and the message it wants to convey is very simple, that is, "little brothers and sisters come to play." So more and more mosquitoes "hear the news", and the pheromones above your head will also be more and more, so it will form an embarrassing mosquito circle that can make mosquitoes "back the black pot"!
Shake the mosquito coil
Pheromones are also known as in vitro pheromones, which are different from hormones, which are secreted in the body to convey some kind of information to their own body, while pheromones are secreted to convey information to other individuals outside the body. It is through various complex pheromones that ants communicate with different individuals in the population.
The "blind date" overhead
So what are the mosquitoes doing above our heads? In fact, the answer is not difficult to guess, many dipteran longhorn insects have a group breeding behavior of marriage and flight, such as stone moths, stone flies, and the rocking mosquito is also one of them.
In the CCTV science and education channel, there was a popular science program with the theme of "Crazy Mosquito", in which Professor Wang Xinhua of Nankai University explained the purpose of the flying mosquito, the reason why the mosquito will fly in marriage is mainly that the cluster can attract more members of the opposite sex, so as to better select the object, and produce a sufficient number of eggs and continue the offspring... On the other hand, number equals safety, and the collective marriage flight of mosquitoes can also create a relatively safe breeding environment to avoid predation.
Screenshot of the show
So, simply put, a mosquito ring above your head is holding a large "blind date", you may lament the madness of the mosquito, but they are also "forced", because once the mosquito larvae are feathered into adults, life enters the countdown, leaving only two weeks of life. Therefore, in the process of marriage and flight, they hardly eat or drink, every second at a time, all in order to complete their mission to continue their descendants in this short period of time...
<h1 class = "pgc-h-arrow-right" > beneficial insect - shake mosquito</h1>
Seeing this, do you think that the swarm of mosquitoes on your head is not so annoying, they are just a little bit of life" without shame, that is, they do not bite and do not suck blood, which is much more cute than those mosquitoes whose stomachs contain our blood and buzz and scream.
In fact, the real situation is indeed so, in addition to the scene of the flying in the sky is a little scary, in many ways for us humans are considered beneficial insects, let's talk about the contribution of the mosquito to our human beings.
Purify water quality
The larvae of the mosquito (hemoglobino) mainly feed on the organic debris at the bottom of the water, and the organic debris in the water is cleaned up to accelerate the mineralization of organic matter in the water material cycle and eliminate organic matter pollution, so it can play a role in purifying water quality.
Monitor water quality
The pupal skin of the mosquito (the translucent skin under the molting of the mosquito when feathering) is a good community research material, if you can obtain a region and river of sufficient mosquito pupae, and clarify the relative number ratio (relative abundance) of different mosquito species in the sample, you can make an objective evaluation of the local water environment, which is also the principle of rapid environmental monitoring using the mosquito pupa.
Collecting the pupae of the mosquitoes can be a bit of a hassle, and there's a more intuitive way to do this – directly look at the number of blood red worms in the waters. Hematodes are good indicators of the water environment and pollution, because they absorb oxygen from water bodies by snorkeling, and the oxygen in the water is produced by the decomposition of debris, organic matter, floating algae, etc. Therefore, when there are more blood red worms in a body of water, or there are more mosquitoes near the water, it should be noted, and it is very likely that the water quality of the place is polluted.
Shake the mosquito pupae
Quantify the environment
The good or bad of the environment is often difficult to truly quantify, and the sediments present in the water environment can be measured by the content of various elements, such as nitrogen and phosphorus, whether they are in a better or worse degree, and can also be measured by shaking mosquitoes.
How do you quantify the quality of the environment? Here the shake mosquito gives the answer! Simply put, the toxicology of the sediment of the mosquito can get the dose of the lethal effect of many pollutants on the mosquito, combined with the amount of pollutants that exist in the environment now, you can give a good evaluation to the environment. That is to say, if some of the mosquitoes that have been selected as subject organisms of the toxicology of the shake mosquito cannot survive at such a level of pollution, then the environment in which such a degree of pollution exists must not be a better environment.
Maintain ecology
Blood red worms have another important role, that is, as bait. When still in the planktonic stage (eggs), it can be ingested by juveniles, and when transferred to benthic (larvae), it can be used as adult feed. Hematodes are rich in nutrients, with protein content accounting for 41% to 62% of dry matter, which can promote the growth and development of fish. In addition, hemocytodes can purify water quality, and many fish farms will raise hemoglobinosts in some waters.
Blood red worms as bait
Trace back to the past
Ecologists and paleocannaographers can restore the ancient environment by a variety of means, and the fossil skull of the mosquito in the sediment is one of the raw materials for their effective speculation.
Because the skull of the larvae is composed of chitin, and the four ages of the larvae, each of the ages of the mosquito larvae will shed their skull and grow new ones during development, and most of the skulls can be preserved in the sediment of water bodies for a long time. Therefore, through the study of chitin classification in the fossil skull of the mosquito in the sediment, the structure of the mosquito cluster at that time can be approximately reproduced, and then the biological conversion function can be used to achieve the reproduction of the environment at that time.
In other words, the change in the cluster structure of the fossil skull of the mosquito can be used as one of the speculative indicators of environmental factors such as water temperature and salinity in this lake and marsh in the past few thousand years. Therefore, the subfossils of the mosquito are more popular than silicon shells and spore powder, which are more popular with paleocannaographers.
Screenshot of literature related to fossilized skulls of mosquitoes
Well, about letting mosquitoes "back the black pot" and "no shame" on our heads to open a "blind date" mosquitoes is introduced here, although they are dense and make people pores intimidating, they are in many ways a beneficial insect for us, so the next time they fly on top of your head, be generous, don't do it...
Some of the image sources are invaded and deleted online