peramorphosis

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peramorphosis Any outcome arising from evolutionary changes in developmental rates (see heterochrony) that involves the addition of new stages to the end of the ancestral development sequence. Peramorphic forms may arise either by acceleration or by hypermorphosis and conform to the theory of recapitulation. In contrast, paedomorphic forms (see paedomorphosis), in which a new stage is added within the developmental sequence, do not exhibit recapitulation.

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