Proterozoic aeon


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Noun1.Proterozoic aeon - from 2,500 to 544 million years agoProterozoic aeon - from 2,500 to 544 million years ago; bacteria and fungi; primitive multicellular organisms
Precambrian, Precambrian aeon, Precambrian eon, Precambrian period - the eon following the Hadean time and preceding the Phanerozoic eon; from about 3,800 million years ago until 544 million years ago