metamorphosis (biology)

Period during the life cycle of many invertebrates, most amphibians, and some fish, during which the individual's body changes from one form to another through a major reconstitution of its tissues. For example, adult frogs are produced by metamorphosis from tadpoles, and butterflies are produced from caterpillars following metamorphosis within a pupa.

In classical thought and literature, metamorphosis is the transformation of a living being into another shape, either living or inanimate (for example Niobe). The Roman poet Ovid wrote about this theme.