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The biota largely disappeared with the rapid increase in biodiversity known as the Cambrian explosion.Most of the currently existing body plans of animals first appeared in the fossil record of the Cambrian rather than the Ediacaran.

They appear to migrate upwards when covered by a thin layer of sediment but this is an illusion caused by the colony's growth; individuals do not, themselves, move.

If too thick a layer of sediment is deposited before they can grow or reproduce through it, parts of the colony will die leaving behind fossils with a characteristically wrinkled ("elephant skin") and tubercular texture.

Due to the difficulty of deducing evolutionary relationships among these organisms, some palaeontologists have suggested that these represent completely extinct lineages that do not resemble any living organism.

One palaeontologist proposed a separate kingdom level category Vendozoa (now renamed Vendobionta) in the Linnaean hierarchy for the Ediacaran biota.

As soft-bodied organisms, they would normally not fossilize and, unlike later soft-bodied fossil biota such as the Burgess Shale or Solnhofen Limestone, the Ediacaran biota is not found in a restricted environment subject to unusual local conditions: they were a global phenomenon.

The processes that were operating must have been systemic and worldwide."Ediacaran" and "Ediacarian" were subsequently applied to the epoch or period of geological time and its corresponding rocks.In March 2004, the International Union of Geological Sciences ended the inconsistency by formally naming the terminal period of the Neoproterozoic after the Australian locality.There was something very different about the Ediacaran Period that permitted these delicate creatures to be left behind and it is thought the fossils were preserved by virtue of rapid covering by ash or sand, trapping them against the mud or microbial mats on which they lived.The rate of cementation of the overlying substrate relative to the rate of decomposition of the organism determines whether the top or bottom surface of an organism is preserved.For macroorganisms, the Cambrian biota appears to have completely replaced the organisms that dominated the Ediacaran fossil record, although relationships are still a matter of debate.

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