When it comes to mosquitoes, I don’t think anyone has ever been tortured. It’s obvious that people’s view on mosquitoes has been very unfriendly. They are often bitten all over and itchy. So why do humans deal with mosquitoes in this way? Let’s start with the mosquito itself.
At present, according to statistics, there are more than 3600 mosquitoes
More than 370 species have been found in China. The most common target is Culex pipiens. It likes to live in a dark and humid environment. The reason why we hate mosquitoes is not only because they are covered with bacteria, but also because they will feel itchy after being bitten by mosquitoes, and they will also have skin pain, and even more serious will be allergic and so on. What’s more frightening is the large number of diseases that mosquitoes can spread, such as yellow fever, malaria, filariasis and so on.
The picture shows the blood sucking process of mosquito mouthparts
When they suck blood, they put six syringe like mouthparts into your skin, pierce and cut the skin with the outer two mandibles, and separate the muscle tissue and provide support with the middle two upper jaws. After finding the blood vessels, use the upper lip to suck, at the same time spit out saliva from the tongue, inject anticoagulant protein to prevent blood coagulation. In these three minutes, it sucks three times of its own weight of fresh blood, leaving an extremely itchy package on your body. What’s more lethal is that it’s likely to have embedded the virus in the blood vessels. Every year, hundreds of thousands of people around the world are bitten by mosquitoes and die of malaria, dengue virus and other pathogens. According to the information, there are more than 80 kinds of mosquito borne diseases, so the global anti mosquito experiment began.
Years of anti mosquito war
China mosquito control experiment:
Aedes albopictus at shazai island and dadaosha experimental site in Guangzhou, China, was almost extinct. They used mosquitoes to kill mosquitoes. Scientists released 200 million fecundity lost male mosquitoes to the two islands in Guangzhou, basically eliminating the mosquito populations of the two islands. At the beginning, the islanders were suspicious of this experiment. Only 13% of the people in Sha Tsai supported it. Although the 200 million male mosquitoes released would not bite people, people still felt uncomfortable releasing so many.
The process of the experiment was not smooth sailing. The scientists first laid 110 ovipositors and 44 mosquito traps, but after eight months of testing, the effect was not very good. The number of mosquitoes decreased very little. However, mosquitoes are the main vectors of malaria and other diseases, which cause millions of deaths every year. Sterilization of mosquitoes is a way to prevent the transmission of diseases.
The picture shows the mosquito killing mechanism of Wolbachia
So scientists began to release more than 200 million male Asian tiger mosquitoes to shazai island and dadaosha in Guangzhou, where dengue fever was very serious. These mosquitoes were infected with three different Wolbachia bacteria through short-term exposure to gamma rays, namely, wAlbA, walbb, and Wolbachia, Wpip, they call this artificial Aedes albopictus HC, and HC mosquito has almost no ability to transmit the virus, and lost the ability to reproduce. Females are more attractive during the mating season, and the eggs laid by females after mating with these males will not hatch.
After two years of experiment, the wild mosquito population basically disappeared. The researchers found that there were still some mosquitoes living on the island, but genetic analysis showed that they came from other places and probably came to the island by means of transportation. The technology has won a great victory. According to statistics, the probability of local residents being bitten by mosquitoes has decreased by 96%. After the experiment, more people supported the technology, and the past suspicions have disappeared.
Not only in China, but also abroad
A life science company of Google’s parent company, alphabet, wants to use advanced technology and algorithms to catch all Aedes aegypti. They decided to release 20 million male Aedes aegypti infected with Wolbachia and infertile in Fresno, USA, and let them mate with female mosquitoes. In order to improve their mating competitiveness, researchers even tried to feed the male mosquitoes with natural food Herbal extracts. In terms of courtship time, mating number and mating success rate, they are slightly better than ordinary mosquitoes who only eat sugar water. Unfortunately, their average life span is less than 70 days, and they live 16 days less. Because of infertility, the eggs are “stillborn” are unable to hatch. And male mosquitoes do not bite, female mosquitoes will bite and infectious diseases. This experiment has really achieved good results. The number of Aedes aegypti is decreasing. In addition, large-scale mosquito control experiments in Australia have been successful, and the main “hero” is Wolbachia to eliminate mosquitoes.
Why not eliminate all mosquitoes
The answer is that it is difficult to exterminate mosquitoes. The main components of common mosquito repellent products are pyrethroids and DEET, which can knock down and drive away mosquitoes by interfering with their nervous system or olfactory perception mechanism. But at the same time, mosquitoes are developing resistance. Therefore, it is very difficult to eliminate mosquitoes. Mosquitoes are small in size, large in number, strong in reproduction, wide in distribution, strong in adaptability, rapid in variation and strong in drug resistance. It seems impossible to exterminate them.
But human beings have also made experiments, although the effect is very good, but not all of them have been eliminated. Moreover, mosquitoes are not all harmful to human beings. Most of them are harmless to human beings. In particular, mosquitoes living in the polar circle of Canada and Russia play an important role in the local ecosystem. Because they fly in groups, they not only pollinate polar plants, but also are the main food source for migratory birds.
The picture shows mosquitoes transmitting pollen
For other areas, mosquitoes may also be food for birds, fish or insects, so it’s never a good idea to let them all die out. And scientists have found some direct solutions to the harm of mosquitoes to human beings without affecting the ecological balance.
In 2015, a British company created a male Aedes mosquito with a “self limiting gene” that prevents its cells from functioning properly. When the defective male Aedes aegypti is released and gives birth to the next generation with the female Aedes aegypti, the gene will be passed on. The larvae with this gene usually can’t grow into adults, and the mosquito will die. Of course, they can’t transmit diseases.
The picture shows the spotted mosquito
There are also scientists in California who have developed ways to deal with malaria mosquitoes. Anopheles is actually a genus of several mosquitoes that can transmit malaria. They are Anopheles because they are parasitized by Plasmodium. So scientists have changed the genes of Anopheles into genes that can kill the Plasmodium, so that even if the Plasmodium parasitizes, it will be eliminated before the Anopheles infect humans! What’s even better is that the probability of this gene being passed on to the next generation is 99.5%! This means that malaria mosquitoes all over the world may not be able to transmit malaria in the future! Scientists think this technology could be used in other mosquitoes as well. In addition to changing genes, some scientists also use the method of “fighting the virus with poison”!
They infected Aedes aegypti with Wolbachia, and found that Wolbachia could prevent most of the virus from surviving in the mosquito body, so even if the mosquito bit the virus carrier, the virus could not survive in their body, and the mosquito would not spread the disease! So it’s not necessary to exterminate mosquitoes. We can change them by some means.
There must be a reason for the existence of mosquitoes
Many people think that “existence is reasonable”. Since mosquitoes exist, they must have their significance. Everything has its advantages and disadvantages. Objectively judge the advantages and disadvantages brought by mosquitoes. For mosquitoes, we should not only think from the perspective of human beings, but also from the perspective of nature. Of course, the most important thing is the benefits to nature. The main thing we want to say about the benefits of mosquitoes is that mosquitoes make great contributions to the ecological balance of nature.
The picture shows the larvae
It can be used as a “pure natural filter” of nature. Most female mosquitoes will lay eggs in the water. Their larvae, larvae, will grow in the water and feed on the floating objects and debris in the water, so that many aquatic organisms will not die due to the lack of oxygen and nitrogen due to the floating objects. As the food of many birds and insects, mosquitoes enable the living creatures to survive. When birds migrate, mosquitoes are indispensable food for them. Without mosquitoes, these birds may run out of food and greatly reduce their chances of survival. Similarly, as the food of many insects, once mosquitoes disappear, the number of insects and birds that feed on mosquitoes will be greatly reduced, which will destroy the ecological balance of a certain place.
Many years ago, a sparrow was the worst disaster for farmers. A Sparrow could eat the food rations of 60000 people at that time every year, so it was regarded as one of the “four pests”. So it began to kill sparrows crazily. However, the good news did not last long. The result of sparrow killing was that the leaves on the trees disappeared, the ticks were all over them, and the trees, fruits and crops in many places became the world of insects, It presents a miserable phenomenon, so any kind of biological existence has its reason.
Not all mosquitoes bite
Mosquitoes do not all bite people to infect the virus. There are many kinds of mosquitoes. The common blood sucking mosquitoes are Culex, Aedes, Anopheles, chironomid, big mosquitoes and so on, especially chironomid, but they have important ecological value. Chironomid and big mosquitoes do not bite people. Only female mosquitoes will suck blood. Most male mosquitoes feed on nectar and dew. So when male mosquitoes collect honey, they certainly help to spread pollen. Finally, as the food of many birds and insects, mosquitoes enable the organisms that feed on mosquitoes to survive. When birds migrate, mosquitoes are indispensable food for them. Without mosquitoes, these birds may run out of food and greatly reduce their chances of survival. Similarly, as the food of many insects, once mosquitoes disappear, the number of insects and birds that feed on mosquitoes will be greatly reduced, which will destroy the ecological balance of a certain place.