Diptera is an order that consists of the "true flies". Flies in the order Diptera are unique because unlike the dragonfly and the damselfly, they can fold their wings along their back. The creationist's view is that these insects were created along with the rest of the insects and animals on the sixth day as recorded in Genesis. Flies under the order of Diptera are considered true flies. The name Diptera comes from the Greek words Di meaning two and Pteron which means wing, giving it a Greek name of two wings, Diptera.
Anatomy The antennas of the Diptera are broken up into 6 separate sections. The main section of the antenna is called the flagellum. The mouthpiece of a fly is called the proboscis which is a similar anatomical organ to the trunk of an elephant. These mouths enable the fly to suck, mainly for the use in eating nectar. In more predatorial flies such as the mosquito the proboscis is a more needle like stylets that can pierce through skin. In some cases the flies have adapted to their environment by losing their wings. This adaptation is evident in the Louse Fly which has lost its wings so that it is capable of staying discrete on their hosts body.
Flies in the Diptera order go through complete metamorphosis. This means that they go through four major stages of life. They begin as an egg. Diptera eggs life span tends to be very short only lasting between 1-7 days on average. The larval stage can take anywhere from two days to two years depending on conditions and time of year. If the larva hatches in raw rotting meat they will grow very quickly. The larva can go through as many as 4-9 instar steps to become an adult.  The next stage that they enter into is the pupa stage this stage takes places during the final instar of the insects life. The final stage is that of the Adult stage. In this stage the fly is ready to mate and start the process over. Many Diptera flies go through a kind of courtship. They do not just mate immediately but spend time together doing certain instinctive actions. Theses actions can vary from certain wing vibrations to air dances and even to the male giving to the female fly a silk balloon with either a bug in it or completely hollow. Diptera flies have a variety of ways to lay their eggs. Most of them involving piercing through a protective covering and laying them inside, be that in fruit, or under human or animals skin. Some other flies lay their eggs directly on a food source such as rotting meat or on the surface of flesh of a living organism. 
The order Diptera live in a wide variety of locations. Mosquitoes tend to live in warm humid places.  This is one of the reasons Africa has such a high death rate from Malaria, a disease carried by mosquitoes. Africa is a hot humid location great for mosquitoes to grow. Other types of flies such as the house fly desire moderate locations and are mostly seen in urban locations thus giving them their name, housefly. Fruit flies will procreate in any location with a high concentration of sweets specifically fruits. Other types of flies prefer to reproduce around and in locations where there is rotten meat, this is the reason for high populations of flies in farm land. 
The evolutionists believe that the flies under the order Diptera came from prehistoric crustaceans. They believe that the wings evolved from a lacking ancestral appendage or leg. They believe this to be the case because they believe that that since the wing and the legs of some prehistoric crayfish and the gene in the Drosophila fly have similar genes that they were originally expressed from the same place. They believe that over time the gene altered itself slightly and resulted in the crustaceans development of a wing. (Purves 650) Another belief of the evolutionists is that they final Diptera order came from a variety a species. They believe that the mouth organ is so complex and there is such a vast variety of variants on the mouth through the order that although they became the same order the came from a large amount of different species evolutionary process to become a fly. 
- Evolutionary Beliefs
- Sci-Tech Encyclopedia
- Purves, William. Life the Science of Biology. 2005. Couriers Company Inc.