The Ediacaran Period, named after the Ediacara Hills of South Australia, is the last geological period of the Neoproterozoic Era and of the Proterozoic Eon, immediately preceding the Cambrian Period, the first period of the Paleozoic Era and of the Phanerozoic Eon.

The Ediacaran Period ( ca.

Although the Ediacaran Period does contain soft-bodied fossils, it is unusual in comparison to later periods because its beginning is not defined by a change in the fossil record.

No dating has been possible at the type section of the Ediacaran Period in South Australia.

These were most commonly known as Vendian biota until the formal naming of the Period, and are currently known as Ediacaran biota.

** Animals that live interstitially in the sand of the ocean floor were responsible for the fossil crawling traces that are considered the earliest evidence of animals and are detectable even prior to the dawn of the Ediacaran Period in geology.

** Animals that incorporated algae as photosynthetically active endosymbionts, i. e. primarily obtaining their nutrients from their partners in symbiosis, were accordingly responsible for the mysterious creatures of the Ediacara fauna that are not assigned to any modern animal taxon and lived during the Ediacaran Period, before the start of the Paleozoic.

The well-identified events of this eon were the transition to an oxygenated atmosphere during the Mesoproterozoic ; several glaciations, including the hypothesized Snowball Earth during the Cryogenian period in the late Neoproterozoic ; and the Ediacaran Period ( 635 to 542 Ma ) which is characterized by the evolution of abundant soft-bodied multicellular organisms.

It forms the second geologic period of the Neoproterozoic Era, preceded by the Tonian Period and followed by the Ediacaran.

They cite the Cambrian explosion — the appearance of abundant fossils in the upper Ediacaran ( Vendian ) Period and lower Cambrian Period — as the pre-Flood / Flood boundary, the presence in such sediments of fossils that do not occur later in the geological record as part of a pre – flood biota that perished and the absence of fossilized organisms that appear later, such as angiosperms and mammals, as due to erosion of sediments deposited by the flood as waters receded off the land.

The impact event is estimated to have occurred about 580 million years ago during the Ediacaran Period ; this age is not derived from the crater itself but from the position of ejecta within nearby sedimentary basins.

The mountains are formed of metamorphic rocks made from sediments deposited during the Ediacaran Period ( as indicated by the presence of characteristic fossils ).

The Roxbury Conglomerate, from which this pot is alleged to have come, has been dated as having accumulated between 570 and 593 million years ago and during the Ediacaran Period.

The stratigraphic range of T. pedum overlaps the range of the Ediacaran fossils in Namibia, and probably in Spain.

The stratigraphic range of T. pedum overlaps the range of the Ediacaran fossils in Namibia, and probably in Spain.

The Cambrian period follows the Ediacaran and is followed by the Ordovician period.

The lower boundary GSSP of the Ediacaran is at the base of the cap carbonate ( Nuccaleena Formation ), immediately above the Elatina diamictite in the Enorama Creek section, Brachina Gorge, Flinders Ranges, South Australia.

The GSSP of the upper boundary of the Ediacaran is the lower boundary of the Cambrian on the SE coast of Newfoundland approved by the International Commission on Stratigraphy as a preferred alternative to the base of the Tommotian Stage in Siberia which was selected on the basis of the ichnofossils Treptichnus pedum.

This is controversial because an age of about 580 million years has been obtained in association with glacial rocks in Tasmania which some scientists tentatively correlate with those just beneath the Ediacaran rocks of the Flinders Ranges.

The terminal Era of the formal Proterozoic Eon ( or the informal " Precambrian "), it is further subdivided into the Tonian, Cryogenian, and Ediacaran Periods.

There is no convincing fossil record of the placozoa, although the Ediacaran biota ( Precambrian, ) organism Dickinsonia appears to be closely allied with this phylum.

However, as with so many Ediacaran life forms, there is great debate surrounding its position in the tree of life, and classification between the kingdom and family level may be unwise.

This rising creates areas of higher altitude, where the air is cooler and ice is less likely to melt with changes in season, and it may explain the evidence of abundant glaciation in the Ediacaran period.

Also, there is fresh appreciation of fossils discovered in the 19th century, but then denied or deprecated: the classic example is the Ediacaran biota from the immediate pre-Cambrian, after the Cryogenian period.

It is a member of the Ediacaran biota.

Its relation to other known Ediacaran biota is no clearer.

There are no identified related forms, although there is some vague resemblance to other Ediacaran forms such as Dickinsonia and Spriggina that share some of its enigmatic characteristics, such as the " staggered " or " glide symmetry " of its units.

Arkarua is known only from the Ediacaran beds of the Flinders Ranges in South Australia, and takes its name from a mythical giant snake of the local Aboriginal people ( Gehling 1987 ).

Dickinsonia is an iconic fossil of the Ediacaran biota.

Dickinsonia is known from unskeletonised impressions in late Ediacaran quartz sandstones in Ediacara and elsewhere in the Flinders Ranges of South Australia, as well as, Podolia of Ukraine, and the White Sea area and Central Urals of Russia, and has an estimated time range of 560-555 Myr .< ref name = Grazhdankin2004 >

Dickinsonia is a " resistant " fossil – that is to say, it is preserved as a ( usually concave ) cast on the underside of overlying bedding planes — unlike most Ediacaran fronds.

The Ediacaran boundaries are the only Precambrian boundaries defined by biologic Global Boundary Stratotype Section and Points, rather than the absolute Global Standard Stratigraphic Ages.

Russian geologists referred to the last period of the Neoproterozoic as the Vendian, and the Chinese called it the Sinian, and most Australians and North Americans used the name Ediacaran.

These are referred to as Ediacaran or Vendian biota.

Ausia fenestrata is a curious Ediacaran period ( 630 – 542 million years ago ) fossil represented by only one specimen 5 cm long from the Nama Group of Namibia and it has similarity to Burykhia from Ediacaran ( Vendian ) siliciclastic sediments exposed on the Syuzma River of northern Russia.

The first evidence of burrowing which is widely accepted dates to the Ediacaran ( Vendian ) period, around.

The producers of burrows Skolithos declinatus from the Vendian ( Ediacaran ) beds in Russia with date have not been found, they might have been filter feeders subsisting on the nutrients from the suspension.

Mistaken Point is the original location of the first documented Ediacaran, Aspidella terranovica ( which gets its specific name from Newfoundland ).

The hills also contain fossils of early multicellular life forms, the Ediacaran biota ( lagerstätte ), and have given their name to the Ediacaran geological period.

Before that, the Proto-Tethys Ocean existed from the Ediacaran ( 600 Ma ) into the Devonian ( 360 Ma ), and was situated between Baltica and Laurentia to the north and Gondwana to the south.

Dickinsonia was first described by Reg Sprigg, the original discoverer of the Ediacaran biota in Australia, who named it after Ben Dickinson, then Director of Mines for South Australia, and head of the government department that employed Sprigg.