Paleoproterozoic

The Paleoproterozoic is an era of Earth's history. Within the Proterozoic eon, it is the oldest era is, it starts before about 2500 and ends before 1,600 million years ago.

The breakdown of the Paläoproterozoikums:

Eon: Phanerozoic ( 541-0 mya )
Aeon: Proterozoic ( 2500-541 mya ) Era: Neoproterozoic ( 1000-541 mya )
Era: Mesoproterozoikum ( 1600-1000 mya )
Era: Paleoproterozoic ( 2500-1600 mya ) Period: Statherium ( 1800-1600 mya )
Period: Orosirium ( 2050-1800 mya )
Period: Rhyacium ( 2300-2050 mya )
Period: Siderium ( 2500-2300 mya )

During the Paläoproterozoikums the still single-celled life to develop. From simple bacteria, the first complex single-celled organisms with developed organelles and later a nucleus ( eukaryotes ). This included the first green algae and the first single-celled animals.