Usually when an animal or plant dies it is completely destroyed. Another animal may eat it or it may decay. But sometimes the remains of an animal are buried before they can be destroyed, and if the conditions are just right, the remains get preserved as fossils.

In some very rare cases, scientists have found fossils of bird feathers and dinosaur skin. But usually only the hard parts of an animal, like teeth, bones and shells, become fossilized. What parts of your body do you think would most likely be preserved by fossilization?

In this exhibit, you will learn about the fossils of invertebrates - animals without backbones.  Snails, clams, worms, and insects are all invertebrates. In fact, 95% of all living animals are invertebrates. This number was even greater in the past.

Although they do not have bones, many invertebrates have a shell or a hard exoskeleton that can be fossilized. The exoskeleton is like a suit of armour, giving the animal support and protection. Modern invertebrates like lobsters, cockroaches, and spiders have exoskeletons.

	Snail lives in ocean.
	Snail dies.
	Dead snail is buried.
	Soft body decays.
	Millions of years later... ... sand hardens to rock and the shell or its imprint is preserved as a fossil.
Illustrations: M. Leverock.

Almost all fossils are preserved in sedimentary rocks, rocks that formed when layers of sediment such as clay, mud, silt, or sand became compressed and hardened over millions of years. These types of sediments are laid down in lakes, swamps and oceans. This is one of the reasons why most fossils are the remains of animals who lived in or near the water.
 

material courtesy of
Royal Canadian Museum                                                                            to Fossil Game
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