Information AboutEdiacaran |
| CATEGORIES ABOUT EDIACARAN | |
| proterozoic | |
| fossils | |
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BASE OF THE EDIACARAN Although the Ediacaran Period does contain soft bodied Fossil s, it is unusual in comparison to later periods because its beginning is not defined by a change in the Fossil Record . Rather, the beginning is defined at the base of a chemically distinctive Carbonate layer, referred to as a " Cap Carbonate ", because it caps glacial deposits and indicates a sudden climatic change at the end of an Ice Age . This bed is characterized by an unusual depletion of 13C, and is considered by many scientists to be of global extent, although this is controversial. DATING BIOTA See Also: Ediacaran biota The animal fossil record from this period is sparse, possibly because animals had yet to evolve hard shells, which make for easier fossilization. The Ediacaran biota include the oldest definite Multicellular Organism s, and the most common types resemble segmented worms, fronds, disks, or immobile bags. They bear little resemblance to modern lifeforms, and their Relationship even with the later lifeforms of the Cambrian Explosion is difficult to interpret. More than 100 Genera have been described, and well known forms include '' Arkarua '', '' Charnia '', '' Dickinsonia '', '' Ediacaria '', '' Marywadea '', '' Onega '', '' Pteridinium '', and '' Yorgia ''. SEE ALSO
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