Quelles parties d'un être vivant sont les plus susceptibles d'être fossilisées ? Pourquoi? or What parts of a living being are more likely...

Fossils are remains or traces of an organism that lived long ago. Fossils dating back to couple of billion years have been found, though fossils of relatively recent organisms (few to few hundred million years old) are more common. When an animal dies, its skin and other organic body constituents gets decayed or eaten by other organisms or scavengers. Ultimately, only the hard body components, such as bones, teeth and shells remain and are capable of surviving the destructive forces of nature. These components are slowest to degrade and hence survive the longest and gets converted to fossils. There are exceptions though. Completely preserved animals have been found as a result of instant freezing after its death. Another such example is the complete fossil of insects trapped inside resin drops.

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