Final answer:
The Proterozoic era ranges from 2.5 Ga to 542 Ma and leads into the Phanerozoic eon, starting with the Cambrian period. The Ediacaran Period is the final period of the Proterozoic, followed by the Paleozoic era with its substantial diversification of life, including the Ordovician period.
Step-by-step explanation:
The Proterozoic era, spanning from 2.5 Ga (billion years ago) to 542 Ma (million years ago), is a significant division of Earth's geological timescale. This era precedes the Phanerozoic eon, which is characterized by abundant animal and plant life starting around 541 Ma with the Cambrian Period. The Proterozoic encompasses several notable periods, including the Neoproterozoic Era and its three periods, one of which is the Ediacaran Period, extending from approximately 635 million to 541 million years ago and serving as the last period of the Proterozoic.
The Paleozoic era follows the Proterozoic, beginning with the Cambrian explosion that marked a significant increase in the diversity of life on Earth. The Paleozoic era lasted from about 544 to 245 Ma and ended with the notorious Permian extinction. The Proterozoic's conclusion set the stage for the earliest periods of the Paleozoic era, which includes the Ordovician, the period between the Cambrian and Silurian periods.