Final answer:
The Proterozoic eon, extending from 2.5 Ga to 541 Ma, precedes the Phanerozoic Eon, which starts with the Cambrian period. The Neoproterozoic era, part of the Proterozoic, is noted for the Ediacaran Period, before the Cambrian Explosion marking the extensive diversification of life.
Step-by-step explanation:
The Proterozoic is a geological eon representing the time just before the proliferation of complex life on Earth. It extends from 2.5 billion years ago (Ga) to 541 million years ago (Ma). The three periods of the Neoproterozoic Era (one of the three eras of the Proterozoic eon) are largely characterized by the formation of the supercontinent Rodinia, its break-up, and the subsequent formation of Gondwana. It is followed by the Phanerozoic Eon, which commenced with the Cambrian period, when rapid diversification of life occurred (known as the 'Cambrian Explosion'). The Cambrian is followed by the Ordovician, the second period of the Paleozoic era, and then by the Silurian. The Paleozoic era ends with the Permian period, followed by the Mesozoic and Cenozoic eras. The Ediacaran Period, existing within the Neoproterozoic era, is known for being the final period of the Precambrian supereon and directly predates the Cambrian.