Cambrian explosion

noun

paleontology

: 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

Word History

First Known Use

1977, in the meaning defined above

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