Fossils can be formed by:MummificationPetrificationDesiccationRelated question on Answers.com:How are fossils formed?
Stromatolites.
The oldest known fossils are prokaryotic. These fossils, dating back over 3.5 billion years, are believed to be ancient bacteria and archaea. Eukaryotic cells are thought to have evolved later.
Maybe. It depends on what kind of rock it is. If its a sedimentary rock and it's pretty old, then it will probably have some fossils in it. If its igneous the chances are not very likely i'd say.
The fossils of the oldest life forms can be found in the Precambrian period of the fossil record.
The oldest humanoid fossils were all found in Africa.
The fossils that are further up among the layers would be newer because they were formed before the others.When fossils are further down in the ground they are older because they had been covered up longer in time.
Yes, the phylum porifera contain some of the oldest organisms because they are formed from fossilized, tiny sea organisms which were the precursors to modern life.
The oldest micro fossils are comprised of carbon. This is because they have been in the ground a very long time and it compresses the materials into carbon.
The oldest known fossils are up to 3.5 billion years old.
Africa
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