Which metamorphosis type includes four life stages: egg, larva, pupa, and adult?

Which metamorphosis type includes four life stages: egg, larva, pupa, and adult?

• A. Egg, larva, pupa, and adult (Complete metamorphosis)
• B. Egg, nymph, adult
• C. Egg, young, adult
• D. Egg, larva, adult

Answer: (A)

Four life stages—egg, larva, pupa, and adult—signal complete metamorphosis. In this pattern, the larval form is usually worm-like and specialized for feeding and growing, while the pupal stage is a transformative, non-feeding phase during which the organism reorganizes into an adult with a very different shape and lifestyle. Because of these distinct stages, many insects such as butterflies and moths, bees and wasps, beetles, and true flies exhibit this four-step development, which helps explain why the adult looks so different from the larva. The other sequences don’t include a pupal stage or don’t show a dramatic difference between juvenile and adult forms. Egg-nymph-adult describes incomplete metamorphosis, where the nymph resembles the adult and there is no pupal transformation. Egg, young, adult isn’t a standard developmental pattern for insects. Egg-larva-adult omits the pupal stage, so it represents a different type of development and doesn’t capture the full transformative process seen in complete metamorphosis.

Four life stages—egg, larva, pupa, and adult—signal complete metamorphosis. In this pattern, the larval form is usually worm-like and specialized for feeding and growing, while the pupal stage is a transformative, non-feeding phase during which the organism reorganizes into an adult with a very different shape and lifestyle. Because of these distinct stages, many insects such as butterflies and moths, bees and wasps, beetles, and true flies exhibit this four-step development, which helps explain why the adult looks so different from the larva.

The other sequences don’t include a pupal stage or don’t show a dramatic difference between juvenile and adult forms. Egg-nymph-adult describes incomplete metamorphosis, where the nymph resembles the adult and there is no pupal transformation. Egg, young, adult isn’t a standard developmental pattern for insects. Egg-larva-adult omits the pupal stage, so it represents a different type of development and doesn’t capture the full transformative process seen in complete metamorphosis.