Mosquitoes pick their victims by smell and composition of the blood. The entomologists from the University of California at Davis have studied the way it happens.
The scientists have analyzed the enzymes contained in the smells of people, as well as chickens and pigeons, which mosquitoes are also fond of biting. The experiment showed that insects were attracted to nonanal aldehyde (it belongs to fragrant substances).
Having studied the reaction of the olfactory receptors of 1300 mosquitoes to this substance, the scientists have found that nonanal activates more than half of them. They also found that mosquitoes were attracted to the increased concentration of steroids or cholesterol on the surface of human skin. That’s why they “love” people who are overweight and have cardiovascular diseases.
By the way, mosquitoes prefer to bite women – especially blondes or pregnant. The exact cause of this is still unclear. Perhaps, the body of these people produces some acid that attracts insects. Furthermore, mosquitoes are drawn to people with increased levels of sex hormones (testosterone or estrogen).