Summer is coming, mosquitoes are coming. Nothing can ruin a wonderful evening date more than the buzz of mosquitoes, which reminds people that its animals are looking for hot food. There are more than 3,000 mosquitoes in the world, which can destroy our nights wherever we are.

　　According to the Spanish newspaper El Pais website on July 24, this is not a joke. These insects are considered to be the world's deadliest animals, causing more than 725,000 deaths each year. Even if we count humans, no other creature can kill so many people every year like mosquitoes.

　　We often have questions about mosquitoes, including why they buzz and why they always bite me instead of others.

　　Mosquitoes buzz not to warn their biting targets, but to attract the attention of others who are ready to mate. They can't stop making that noise. It just sounds louder when they circle around your head looking for a place to fall and bite.

　　Although both male and female mosquitoes make this noise, it must be female mosquitoes that buzz around you, because male mosquitoes don't bite, they feed on nectar.

　　Both male and female mosquitoes need each other for mating. Entomologist Louis Marcus Roth devoted his youth to helping the U.S. Army study mosquito-borne yellow fever. In an article published in 1948, he pointed out that as long as female mosquitoes rest silently, they will be ignored by male mosquitoes.

　　Let's take a look at the reasons and ways in which female mosquitoes pick their targets.

　　Mosquitoes find targets based on carbon dioxide. When we exhale from the lungs, the carbon dioxide we emit does not immediately mix with the air. Mosquitoes track the scent of carbon dioxide that persists temporarily.

　　Mosquitoes can detect this scent and, like hounds, track it by sensing carbon dioxide concentrations higher than normal air. Through carbon dioxide, mosquitoes can locate targets up to 50 meters apart.

　　When mosquitoes are about a metre away from a group of potential targets, the situation begins to vary from person to person.

　　At close range, mosquitoes take into account many factors that vary from person to person, including skin temperature, clothing color, etc. Scientists believe that the most important variable that mosquitoes consider when choosing specific biting targets is the compounds produced by microbial flora living on human skin. Bacteria convert secretions of human sweat glands into volatile compounds, which are sensed by the mosquito's olfactory system. These complex compounds are more than 300, depending on each person's genes and environment.

　　Because we can't control the microbes on our skin, we can't do much, except wear less black clothes, because mosquitoes like this color best.