Cambrian explosion


Definition of Cambrian explosion

: the emergence of many new organisms including most ancestral lineages of present-day animal species that occurred at the beginning of the Cambrian period This “Cambrian explosion” marks the advent (at least into direct evidence) of virtually all major groups of modern animals—and all within the minuscule span, geologically speaking, of a few million years.— Stephen Jay Gould, Wonderful Life, 1989 … he found a shale outcrop, about the length of a city block, containing an unrivaled array of fossils from soon after the moment when complex life burst forth in dazzling profusion—the famous Cambrian explosion.— Bill Bryson, A Short History of Nearly Everything, 2003

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First Known Use of Cambrian explosion

1977, in the meaning defined above

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The first known use of Cambrian explosion was in 1977

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Cambrian explosion

Cambrian Mountains

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Cite this Entry

“Cambrian explosion.” Dictionary, Merriam-Webster, Accessed 8 Dec. 2021.

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