Metamorphosis is when a species changes body shape and structure at a particular point in its life cycle, such as when a tadpole turns into a frog. Sometimes, in locusts for example, the juvenile form is quite similar to the adult one. In others, they are radically different, and unrecognisable as the same species. The different forms may even entail a completely new lifestyle or habitat, such as when a ground-bound, leaf-eating caterpillar turns into a long distance flying, nectar-eating butterfly.

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