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The Life Cycle of Drosophila

Drosophila is a genus whose members are commonly called fruit flies, vinegar flies or wine flies. The common name developed because genus members are often observed around rotting fruit. Some members of the genus are called "picture-wing" flies because of the variable shading and spotted areas on their wings. There are over 1,500 known species of fruit flies in the world. The majority of species are found in tropical areas throughout the world. The most well-known member of the genus is Drosophila melanogaster. This is the fruit fly used by scientists for studying genetics and biological development.

Mating
- The life cycle of the fruit fly begins after the male and female courtship and mating. Males congregate in groups near potential egg-laying areas to court females. After mating, the female finds decaying fruit, plant, fungal or organic material on which to lay eggs. Females lay single to multiple eggs depending upon their species, habitat and environmental conditions. The eggs are laid near yeast and bacteria growing on the decaying materials. The yeast and bacteria are the food for the developing larvae.
Eggs, Embryos and Hatching
- An embryo begins to develop inside the egg immediately after it has been laid. The embryo develops into a first stage (first "instar") larva in one to three days. The larva emerges from the egg casing and begins feeding immediately.
Larval Growth
- After emerging from the egg, the first instar larva feeds continuously for one or more days depending on species and environmental conditions. The rapid growth of the larva causes it to outgrow its skin. At this time, it molts into a second instar. The second instar eats for three to five days until it is time to molt into a third, and final, larval instar. After feeding for five to ten days, the third instar pupates.
Pupation and Metamorphosis
- The third instar larva becomes stationary and changes into a pupa. The pupa is a resting stage that allows metamorphosis to occur within the pupal case. During this stage, the pupa develops into a three-segmented adult with compound eyes, legs and wings. The time spent as a pupa can vary with Drosophila melanogaster requiring five days to metamorphose from a pupa to an adult.
Renewal of the Cycle
- The adult fruit fly emerges from the pupa after metamorphosis is complete. The adult comes out of the pupa full-sized and fully formed. The adults reach sexual maturity in about 10 hours after leaving the pupal case. The males begin courting females to begin the cycle anew. The life cycle of Drosophila can take from seven to 60 days depending on the species, temperature, food availability and other environmental factors.

Insects & Science