adaptive radiation

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adaptive radiation
1. A burst of evolution, with rapid divergence from a single ancestral form, that results from the exploitation of an array of habitats. The term is applied at many taxonomic levels (e.g. the radiation of the mammals at the base of the Cenozoic is of ordinal status, whereas the radiation of ‘Darwin's finches’ in the Galápagos Islands resulted in a proliferation of species).

2. A term used synonymously with cladogenesis by some authors. (Such a use is misleading, because cladogenesis involves the division of one species into two and adaptive radiation imposes no such constraint.)

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