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Most Common Fossils of America

Stating the most common fossils found in the United States is not an easy task. New fossils are consistently discovered across each state in the U.S. There are, however, typical fossils that are most often found in states or entire regions in the United States. Many of the fossils date back before the dinosaurs while other fossils are from more recent times in North American history.

State Advocacy
- Many states are proud of the fossils that are commonly found across geographic areas of their states. For example, the Commonwealth of Pennsylvania declared the trilobite, an animal that lived almost 570 million years ago, as the State Fossil of Pennsylvania. This is because fossil hunters can find many trilobite fossils across rock formations in central Pennsylvania.
Regional Discoveries
- The American Southeast, or as far north as West Virginia and as far south as Florida, is home to unique fossils. This is because, geologically speaking, the Atlantic Ocean stretched over the American Southwest, covering the Appalachian Mountain range. As a result, fossil enthusiasts can find marine fossils embedded in the rock of Appalachian Mountain ranges. Everything from shark skeletons in Georgia to the remains of primitive whales in Mississippi and Alabama are found in these states, dating back to the Tertiary period (65 million to 2.6 million years ago).
The Southwest
- Similarly, the Southwest of the United States, particularly Arizona, was at one point submerged underwater. You can see evidence of this by looking at mountain ranges or the Grand Canyon in Arizona; there is not only fossil evidence of marine life in the mountains, but also erosion markers that paint the mountains in different sediment colors. The Paleontological Society of the United States, an advocate group for professional or novice fossil hunting across the U.S., outlines that within many counties in Arizona, a fossil enthusiast can discover different fossils from different time periods in the layered sedimentary rock that makes up many Arizona mountain and canyon ranges.
Not What Is Expected
- Although many people think of dinosaurs when they think of fossils, the United States has mostly marine animal lifeforms throughout all 48 continental states. This is because most of what is now the United States was covered under water for millions of years. Residents in Ohio, for example, are more likely going to find fish or fossilized aquatic bacteria in rock than a dinosaur. This does not mean that dinosaurs did not roam what is now the United States. Instead, it means the land that now makes up the United States was covered in the oceans, wetlands, or large lakes, each filled with large amounts of prehistoric life.

Animals & Science