Scientists have never fully understood how mosquitoes distinguish the smell of human breath and sweat from other odors in nature. To learn more, molecular biologist John Carlson at Yale University and colleagues relied on a mutant strain of fruit fly. Each of a series of mosquito genes that code for smell receptors was transplanted, individually, into the fruit flies, which have an “empty” smell-detecting neuron lacking smell receptors
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The Nose Knows: How Malaria Mosquitoes Sniff Out Human Targets [Slide Show]