The Early Pleistocene (also known as the Lower Pleistocene) is a subepoch in the international geologic timescale or a subseries in chronostratigraphy, being the earliest or lowest subdivision of the Quaternary period/system and Pleistocene epoch/series. It spans the time between 2.588 ± 0.005 Ma (million years ago) and 0.781 ± 0.005 Ma. The Early Pleistocene consists of the Gelasian and the Calabrian ages.
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Early Pleistocene Wikipedia(Text) CC BY-SA