In the southeastern United States, Alabama has some of the most diverse marine fossil records. Many parts of the state were covered by shallow seas that connected to the Gulf of America during the Cretaceous, Paleocene, and Eocene periods. Marine environments produced rich habitats for sharks, rays, bony fishes, and other types of fossils.

Fossil-rich formations such as the Lisbon Formation and the Claiborne Group host numerous shark and ray species, as well as bivalves, gastropods, and foraminifera. Fossil records contribute to Alabama’s importance in understanding marine ecosystems during global climatic transitions.

Recently, I visited Andalusia, located in Covington County, Alabama. This area sits above marine deposits from the middle Eocene period. Millions of years ago, Covington County was covered by a warm and shallow marine shelf with conditions similar to today’s northern Gulf of America waters. Sediments that settled on the sea floor became the fossil-bearing layers that are now exposed throughout the county.

Taking from what I learned in Shark and Ray biology, a summer class taught at the Dauphin Island Sea Lab, I searched and sifted for marine fossils at Point A Dam in Andalusia. While going through the sedimentary layers of clay and sand-rich material, I found a variety of fossils, including shark teeth, stingray plate fragments, and stingray barb fragments.

The Andalusia area’s fossil record provides essential insights into Eocene sea conditions, including warm-water temperatures, shallow marine environments, and the biodiversity of Gulf Coast ecosystems before the rise of modern whale and shark lineages. Overall, the region provides a window into what coastal Alabama looked like during a period of high global temperatures and elevated sea levels.

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