How can a whole organism be preserved

Only dead organisms that are buried quickly or protected from decay can become fossils. Generally only the hard parts of organisms, such as wood, bones, shells, and teeth, become fossils. In rare cases, an entire organism may be preserved. In some types of fossils, only a replica of the original organism remains.

Organisms often preserved by carbonization include fish, leaves and the woody tissues of plants. permineralization or petrifaction takes place in porous materials such as bones, plants and shells.

Organisms often preserved by carbonization include fish, leaves and the woody tissues of plants. permineralization or petrifaction takes place in porous materials such as bones, plants and shells