Shortly before or after mating, she takes a meal of blood to provide the eggs with protein. When the eggs are mature and ready to be fertilized, the female searches for a suitable place to lay them which is usually water that is full of decaying matter that includes bacteria and minute organisms. In such situations, the eggs lapse into a state called diapause and they will not hatch until this dormant period passes, and the water level, temperature, and oxygen content are just right. The eggs of some species can survive for years in diapause, even in sub-freezing temperatures. The fans, or brushes, create currents in the water that direct food toward the larvae's mouthparts and help stuff the food into their deeply concealed mouths.
Male mosquitoes drink only sugary fluids such as flower nectar.
Both in the wild and in the laboratory, mosquitoes will visit certain flowers and will feed on fruit placed in their cage. Since they vigorously probe the flowers of some plants, and can distinguish between different types of sugars, they play a role in the pollination of certain plants. The females will also drink sugary fluids, but when hungry females are given a choice between sugar water and blood, they will always choose blood. If males are offered the same choice, they will always drink the sugar water. To better understand the complexity of what is involved in the act of blood feeding, we need to know something about the anatomy of the mosquito's proboscis and alimentary canal.