In aphids, wing production is dependent on what?

• A. Wing production depends on environmental conditions
• B. Wing production is fixed genetically and always present
• C. Wings are produced only during winter
• D. Wings are never produced in males

Answer: (A)

Wing production in aphids is governed by environmental conditions, illustrating phenotypic plasticity. Aphids produce two morphs, winged and wingless, and the choice between them isn’t fixed in the genes alone. Cues such as crowding, the quality of the host plant, and other environmental stresses influence which offspring develop wings. Under crowded or poor-quality conditions, winged individuals are favored because their wings allow dispersal to new plants. When conditions are favorable and resources are abundant, wingless individuals predominates to maximize rapid reproduction on the same plant. This environmental responsiveness is why wing production depends on environmental conditions rather than being a constant trait.