Review

 

Some structures are preserved in the fossil record more easily than others. Some body structures are soft, like skin and muscle. Other structures are hard, like bones, teeth, shells and wood. Hard body parts are more likely to fossilize than soft body parts. It is easier for hard structures such as bones, teeth, shells and wood, to be preserved as fossils because they are less likely to be destroyed by physical and biological factors. Where an organism dies helps determine whether or not it becomes a fossil. The ocean floor and lakes are more likely to fossilize organisms. The coastline and rain forests are not. Many organisms never become part of the fossil record.You just learned that not all organisms have an equal chance of fossilizing.

 

The important factors to consider:

a) avoiding scavengers and decomposers

b) having hard body structures

c) dying in the right place

 

In order to become a fossil all of these factors are important. This means that many organisms never become part of the fossil record! Paleontologists estimate that fewer than 10% of all the organisms alive today will be preserved as fossils. Remember, not all types of organisms preserve well.

 

Only some of the remains of organisms that die resist destruction from physical and biological factors. Organisms live and die in different environments. Some fossils will be destroyed by Earth’s forces, leaving even less evidence of life in the past. Of those fossils that do exist, only some will be found and studied. Below is a chart that shows how hard it is to actaully be preserved as a fossil. The brown dots will take you to the corresponding factors if you cannot recall the processes and perhaps a new page.