So studies have found that pregnant women for example, tend to be singled out by mosquitoes because of their elevated body temperate. And obese people have been found to suffer more bites because larger people simply produce more CO2. Though mosquitoes can also detect a whole range of chemical compounds coming out of us that we're not even aware of, like lactic acid, which we produce by metabolizing milk, and octenol, a type of alcohol we secrete after eating certain kinds of fatty acids. But the craziest way mosquitoes discriminate is based on our blood type.