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. 1971 Nov 19;174(4011):825-7.
doi: 10.1126/science.174.4011.825.

Precambrian columnar stromatolite diversity: reflection of metazoan appearance

S M Awramik

Precambrian columnar stromatolite diversity: reflection of metazoan appearance

S M Awramik. Science. .

Abstract

Columnar stromatolites (organosedimentary structures built by bluegreen algae) show a marked decrease in diversity in the Late Precambrian; this decrease in diversity occurs at approximately the same time as the appearance of metazoans, 600 to 700 million years ago.

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