Ph.D. Candidate, School of Natural Resources and Environment
222 Dickinson Hall
Museum Road & Newell Drive
Gainesville, FL 32611
Masters of Science, Department of Geology, University of Florida, 2004
Age and growth of fossil lamnoid sharks; systematics of lamnoid sharks; age and growth of fossil and extant tortoises; evolution of emydid turtles.
Primary Faculty Advisor: Dr. Bruce J. MacFadden
Macroevolution of Body Size in the Lamnoid Sharks
The goal of my project is to investigate changes in body size within lamnid and otodontid sharks in the fossil record. Using fossilized vertebral centra and sharks' teeth, we can reconstruct growth patterns, ontogenetic changes, and total body lengths for these groups. The otodontid sharks are extremely interesting in that they attained the largest sizes of any sharks known, in excess of 50 feet. Understanding their life histories may help us to understand why this group went extinct during the late Pliocene.
Ehret, D. J., B. J. MacFadden, and R. Salas-Gismondi. In Press. Caught in the act: trophic interactions between a 4 million year-old white shark (Carcharodon) and mysticete whale from Peru. Palaios.
Ehret, D. J., G. Hubbell, and B. J. MacFadden. 2009. Exceptional preservation of the white shark Carcharodon (Lamniformes, Lamnidae) from the early Pliocene of Peru. Journal of Vertebrate Paleontology 29(1): 1-12.
Ehret, D. J. 2007. Skeletochronology: a method for determining the individual age and growth of modern and fossil tortoises (Reptilia: Testudines). Bulletin of the Florida Museum of Natural History 47(2):49-72.
Ehret, D. J., and D. Parker. 2005. Geographic distribution note of Trachemys scripta elegans. Herpetological Review 36:78.
Ehret, D. J., and R. Werner. 2004. Natural history note on the diet of Malaclemys terrapin terrapin. Herpetological Review 35:265.
Ehret, D. J. Methodes de protection et recherches effectueees sur la Malaclemmyde du Nord (Malaclemys terrapin terrapin) par l’Institut des zones humides de Stone Harbor, (New Jersey, USA). Manouria 6(19):30-33.
Werner, R., D. J. Ehret, and L. M. Jensen. 2003. Health assessment of captive raised and wild diamondback terrapins (Malaclemys terrapin terrapin). Bulletin of the New Jersey Academy of Sciences 47:21-25.
Grants and Awards
SNRE/IFAS Travel Grants (2007) – University of Florida
J. Larry Landers Student Research Award (2003) – Gopher Tortoise Council
Mitchell Hope Fellowship (2003) – Tampa Bay Fossil Club
Lucy Dickinson Fellowship (2002) – Florida Museum of Natural History