Mosquitoes are very versatile organisms that can reproduce in any deposit of water, whether man-made or natural. They are found in all climates, even in deep mines and mountain peaks. Very polluted water can even be used in the life cycle of these mosquitoes. They belong to the insect order Diptera in the family Culicidae. It is believed that at least 200 species of mosquitoes in at least 13 genera live in the United States alone.
All mosquitoes have a common four-stage life cycle (egg, larva, pupa, adult). Female mosquitoes lay their eggs individually or in groups, called rafts. The egg hatches in water or wet areas as a larva. The larva grows and molts four times and then becomes a pupa. The pupa transforms the larval organs into adult form. This takes an average of three to four days, depending on individual species and the temperature. The adult then emerges and flies away. The life cycle of Aedes aegypti is shown in the image on the right.