Final answer:
The main purpose of the larval phase of metamorphosis is functional specialization and adaptation to different environments and lifestyles.
Step-by-step explanation:
The main purpose of the larval phase of metamorphosis is to allow for functional specialization and adaptation to different environments and lifestyles. During the larval phase, insects undergo significant structural, physiological, and behavioral changes to prepare for life as an adult. For example, in insects with complete metamorphosis like butterflies, the larvae, or caterpillars, are specialized for feeding and growth, while the adults are specialized for reproduction and dispersal. This division of labor between larval and adult stages increases their chances of survival and reduces competition for resources within the same environment.