1. Egg: Flies begin their life cycle as tiny, white oval-shaped eggs. These eggs are usually laid in clusters or masses by female flies on various surfaces, such as food, soil, garbage, or moist organic matter. The eggs are incredibly small and can be barely visible to the naked eye. Inside the eggs, the embryonic development takes place, and the eggs start to develop into maggots.
2. Larva (Maggot): After hatching from the eggs, flies enter the larval stage, commonly referred to as maggots. Maggots are typically small, worm-like creatures with a segmented body and no visible head or legs. They are commonly found in decaying organic matter, where they actively feed and grow. Maggots have mouth hooks or specialized mouthparts that allow them to break down and consume decaying organic materials, such as rotting fruits, vegetables, or animal carcasses. During the larval stage, maggots go through several instars, shedding their outer skin as they grow larger.
3. Pupa (Cocoon): As maggots reach a certain size and complete their larval development, they enter the pupa stage. During this stage, maggots undergo a significant transformation inside a tough, protective outer shell or cocoon. The pupae are immobile and usually attached to a surface. Inside the cocoon, the maggots' body undergoes a dramatic change, developing adult fly structures, such as wings, legs, antennae, and compound eyes.
4. Adult Fly: Once the transformation is complete, adult flies emerge from the pupae. Newly emerged flies are soft-bodied and pale in color, but their bodies quickly harden and darken. Adult flies have fully developed wings, allowing them to fly and move freely. They have piercing-sucking or sponging mouthparts, depending on the species, and are capable of feeding on a wide range of food sources, such as nectar, pollen, rotting organic matter, or blood (in the case of some species). Adult flies are primarily involved in reproduction, finding suitable mates, and finding food. The adult flies lay eggs, and the life cycle repeats itself.
The duration of each stage and the complete life cycle of a fly can vary depending on the species and environmental conditions, such as temperature and humidity. Generally, the time from egg to adult can range from a few days to several weeks.