Fossil Types

Molds
Casts
Trace Fossils
Coprolites
False Fossils


WEB Sites

Microsoft ® Encarta Encyclopedia
Fossil Types. Zoomschool


References:

Fossils: Clues To The Unknown Past by Joyce R. Blueford, Ph.D.


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Fossil Types

 

Fossils may be preserved in a number of different ways, but they can be placed into two groups, Direct Evidence, and Indirect Evidence. With direct evidence, ancient organisms are preserved without any alteration. The typical type of direct evidence is when an organism's bones, shell, or teeth, their hard body parts, are fossilized. In the rare case, soft body parts may actually be preserved, giving us a rare look at the organisms organ system. In both cases, the only changes in the original body composition is that the less stable organic material has been removed. Hard body parts can also be completely changed or replaced. This is called preservation with alteration. Examples of preservation with alteration include carbonization, permineralization, recrystallization, and replacement.

Where direct evidence gives tells us about the organism's anatomy, indirect evidence gives us information about how the organism lived. Indirect evidence includes mold and casts, tracks and trails, burrows and borings, and coprolites.