Eocambrian Period

The Ediacaran Period, the final division of the Proterozoic Eon, spanned from approximately 635 to 541 million years ago. It followed the Cryogenian Period and preceded the Cambrian Period. This era is significant for yielding the earliest evidence of multicellular animal evolution, known as the Ediacara fauna. These were primarily soft-bodied invertebrates that existed before the Cambrian explosion, a period of rapid diversification of life. The Ediacaran also saw the first evidence of sexual reproduction.1

The period began with the retreat of glaciers and a rise in oxygen levels. Geologically, it was marked by significant tectonic activity, including the formation of the supercontinent Pannotia. The Ediacara fauna, discovered in places like the Ediacara Hills of Australia, included diverse, unusual forms that have sparked debate regarding their exact nature and evolutionary placement.1