Proterozoic (redirected from Proterozoic era)
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Related to Proterozoic era: Mesozoic era
, Palaeozoic Era
, Precambrian era
, Cambrian era
Proterozoic that period of geological time lasting from some 2600 million to 589 million years ago; the part of Cryptozoic time excluding the Archaean Period. Fossils dating from this period are mainly CYANOBACTERIA.