The Ediacaran biota is a taxonomic period classification that consists of all life forms that were present on Earth during the Ediacaran Period. These were enigmatic tubular and frond-shaped, mostly sessile, organisms. Trace fossils of these organisms have been found worldwide, and represent the earliest known complex multicellular organisms. The term "Ediacara biota" has received criticism from some scientists due to its alleged inconsistency, arbitrary exclusion of certain fossils, and inability to be precisely defined.
Life in the Ediacaran Period, as imagined by researchers in 1980.
Palaeontologist Guy Narbonne examining Ediacaran fossils in Newfoundland
Modern cyanobacterial-algal mat, salty lake on the White Sea seaside
A reconstruction of the Ediacaran biota at the Field Museum in Chicago
The Ediacaran is a geological period of the Neoproterozoic era that spans 96 million years from the end of the Cryogenian period at 635 Mya to the beginning of the Cambrian period at 538.8 Mya. It is the last period of the Proterozoic eon as well as the last of the so-called "Precambrian supereon", before the beginning of the subsequent Cambrian period marks the start of the Phanerozoic eon, where recognizable fossil evidence of life becomes common.
The 'golden spike' (bronze disk in the lower section of the image) or 'type section' of the Global Boundary Stratotype Section and Point (GSSP) for the base of the Ediacaran System
The 'golden spike' marking the GSSP
Archaeaspinus, one of the members of the Ediacaran biota which is one of the representatives of the Phylum Proarticulata which also includes Dickinsonia, Karakhtia and numerous other organisms.