Types Of Fossils

If you asked five different paleontologists how many different types of fossils exist, you may get five different answers. The reason is that fossils can be categorized in a number of different ways. One way is by the type of specimen in the fossil (plants, vertebrates, invertebrates) and another way is the method by which the fossil occurred, and yet another categorization would consider whether the fossil included body parts (leaves, teeth, bones, skin, embryos, etc.) or traces (footprints, teeth marks, excrement, etc.).

Different Types of Fossils

Despite the fact that the majority of fossils on record are derived from plants and other animals, children and adults share a fascination with dinosaurs. These vertebrate fossils are mainly found in Canada and the Western part of the United States, although specimens have been found in many other countries. The vertebrate categories would also include the great wooly mammoths, fish, sharks and birds. Common invertebrate fossils include the Burgess Shale, trilobites and crinoids. Plant fossils have been discovered all over the world and include petrified wood and fossilized pinecones.

Fossils can be classified according to their formation, such as: mold, fast, trace, and true form. Mold fossils are like a "negative image" of the specimen. In other words, an impression was made, leaving a "mold" of the original form. Cast fossils are similar, formed when the "negative image" mold is filled with rock or minerals. Trace fossils, also known as ichnofossils, include footprints, nests, animal waste, etc. Finally, true form fossils, such as insects preserved in amber or a shark's tooth, are fossils that include the actual plant, animal, or part of an animal.

By studying fossils, scientists can learn a tremendous amount about these prehistoric animals, including dinosaurs. Fossilized body parts, such as embryos, skin, bones, claws, teeth, etc., give clues as to how the animals looked, how their bones were structured and how they moved. Fossilized traces, or "proof" that these animals once walked the earth, allows scientists to speculate on how the animals behaved, including activities such as hunting, mating, nesting and migrating. The excavation and preservation of fossils can also help paleontologists determine how a plant or animal died and eventually became extinct.