PALEOARCHEAN ERA (3.600-3.200 Ma)
From Greek palaiós (ancient) and arkhaîos (archaic).

Main events: the ancestor LUCA (Last Universal Common Ancestor) is the organism of which all the organisms who lived and live on the Earth descend.

Lifeforms: LUCA was a single-celled microscopic organism, without any distinct nucleus, that reproduced asexually via duplication of its own genetic material and bipartition of the cell, which lived in the hydrothermal vents in the ocean depths.

Paleoenvironment: it is believed that there was a first supercontinent named Vaalbara.