The field of shark paleoecology often yields indecisive conclusions based on the limited fossilization of their anatomical structures, with the exception of their teeth. The majority of the Atlantic coast has been studied regarding the presence of certain prehistoric shark species from the Miocene, Pliocene, and Pleistocene epochs. However, information pertaining to the Georgia coast and understanding its potential community structure is relatively understudied. This study was conducted in which thousands of fossil shark specimens and subsequent marine fauna were collected from dredge spoils created by the US Army Corps of Engineers (USACE): Savannah District. A total of 5,127 fossil shark teeth were collected, of which 4,981 were identified. Twenty-three potential species are believed to be included in this assemblage. Previous research conducted by the U.S. Geological Survey in 2001 shed light on the fossil formations beneath Brunswick, including their specific depths below sea level. Further communication with the USACE detailed their annual dredging depths of 36, 38, and 41 feet below the Mean Lower Low Water (MLLW). By combining this information with the known life histories of each of the 23 species of prehistoric sharks, it was determined that all species potentially coexisted from a time period spanning the late Miocene to early Pliocene (8.0-3.0 Ma) and were preserved in the Ebenezer Member 5 formation. Continued research regarding the ecological roles of all identified shark species will elucidate the community structure of coastal Georgia during the late Miocene and early Pliocene.
We would like to thank to Mr. Jason Kowinsky, Mr. Joe Cocke, and Dr. Lisa Whitenack for helping in the identification process as well as formulating a feasible research goal for the study. This paper could not have been possible without the feedback received from Dr. Kimberly Takagi, Dr. David Stasek, Dr. Tate Holbrook, and Dr. Robin McLachlan. Modern, non-fossilized specimens (used for specimen comparison) were provided by Rob Robins from the Florida Museum of Natural History – University of Florida. A Parotodus benedeni tooth specimen was donated by Jaime Bracewell. Lastly, we would like to thank the U.S Army Corps of Engineers: Savannah District for detailing their dredging operations which aided in the age determination of the collected fossils.
Clark, Joshua Lee and Angalet, Benjamin
"Analyzing the Shark Paleoecology of Coastal Georgia From the Miocene and Pliocene Epochs,"
Georgia Journal of Science, Vol. 81, No. 2, Article 16.
Available at: https://digitalcommons.gaacademy.org/gjs/vol81/iss2/16