Even if an organism is buried, there is no guarantee that it will fossilize.

Have you ever picked up a handful of dirt and found all sorts of worms and other living things crawling around?

Dead organisms that do get buried can be destroyed by biotic and abiotic factors within the sediments.

Many different types of organisms live in soil and feed on organic matter that accumulates there. Some of these organisms are macroscopic such as fungi, earthworms, nematodes, and beetles. Others are microscopic such as bacteria and some protists.

Abiotic factors such as groundwater can also prevent the preservation of an organism by washing it away before it can fossilize.

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