Why do many aquatic insects retain fully functional wings despite spending most of their life cycle underwater?

Answer

To provide an escape route from drying ponds or find new habitats

A notable characteristic of many water bug families, even those deeply committed to aquatic life cycles, is the retention of fully functional wings. While wings might cause drag during submersion, their persistence suggests a strong selective pressure favoring terrestrial dispersal capability. Having wings allows these insects to escape rapidly if their pond dries out or provides a mechanism to locate and colonize new, viable freshwater habitats, balancing the specialization for water against the needs of terrestrial mobility.

Why do many aquatic insects retain fully functional wings despite spending most of their life cycle underwater?
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