Digging into History: College’s Microfossil Research Lab Works to Unearth Glynn County’s Past

By: Tiffany King

Glynn County is known for its beautiful coastline, live oaks and Southern charm. But beyond the sand dunes and flowing marshes are fossils that tell a unique story from long ago. Did you know that the fossilized tooth of a Columbian mammoth was found in Brunswick? Hamilton Cooper discovered the fossil around 1838 during the construction of the Altamaha Barge Canal. He passed it along to Sir Charles Lyell, one of the founders of modern geology, during Lyell’s visit to Georgia. Lyell then gave it to Hugh Falconer, a Scottish botanist, geologist and paleontologist, who used the fossil to establish a new species—Elephas columbi, which was later renamed Mammuthus columbi, better known as the Columbian mammoth.

The discoveries hidden beneath the soil didn’t end there. Fast forward to when a teenage Joshua Clark—now a senior lecturer of biology at the College of Coastal Georgia—stumbled upon a fossil while fishing. He and his twin brother, Kelly Clark, now a lecturer of biology and geology at the College, found more fossils and named the new site Clark Quarry. In 2023, the Clark brothers established the College’s Microfossil Research Lab, which focuses on the discovery and identification of microscopic fossils from Clark Quarry. Since the lab’s founding, students have completed 13 independent research projects, and the program continues to grow.

Clark Quarry was discovered by accident. One day, Joshua Clark decided to go fishing off the marsh on his family’s property, and walked to the edge of the Altamaha Barge Canal. He noticed something in the water and thought it was a bison jaw. He told his brother, and both returned to search for more fossils. What they found included part of a mammoth jaw with a tooth still intact, along with other fossils. With a shared love for dinosaurs and fossils, they knew they had discovered something significant.

They brought their findings to local experts—professors at what was then Coastal Georgia Community College. The professors confirmed that some of the fossils were most likely from a bison. The Clarks were referred to the University of Georgia and then to Georgia College & State University, where they met biology professor Dr. Al Mead. In 2001, Mead coordinated a dig next to the canal. The Clarks later earned master’s degrees with a focus on paleontology from Georgia College. Their paths eventually led them back to the College of Coastal Georgia as instructors.

Clark Quarry continues to be excavated through a partnership between the College, Dr. David Patterson—a biology professor at the University of North Georgia—and Georgia College. Fossils from the quarry date back to the Late Pleistocene during the last ice age, around 22,000 years ago.

Patterson’s research students focus on macrofossils at the site, while Coastal Georgia students study microfossils. As UNG students dig for larger fossils, sediment is scooped into buckets. Once full, the buckets are passed out of the pit to a screen table, where water is poured over the sediment to flush out finer particles. Larger pieces—including rocks, iron nodules, fossils and microfossils—are left behind. These items are washed, dried, and taken back to the Microfossil Lab for sorting and review under a microscope. Digs at Clark Quarry have produced fossils of the Columbian mammoth, long-horned bison, horse, white-tailed deer, giant tortoise, alligator, capybara, gar, sharks, rats, salamanders, amphibians and more.

Fossil tooth from a bowfin (Amia calva), a freshwater fish.

Fossil of a jaw from a green anole (Anolis carolinensis), a lizard.

When Coastal Georgia junior Emma Robison first started in the lab, she worked on sorting and reviewing fish microfossils. Her interest later shifted toward studying biodiversity and diversity indices in ecology, which are used to paint a picture of what the environment is like in a given area. Ecological indices are quantitative measures used to assess biodiversity, species richness, and the overall health of ecosystems. These indices provide a way to compare the condition of different environments. Robison’s project focuses on adapting ecological indices for paleontology.

“Diversity indices were built to assess the level of diversity in a modern ecology, and I’m trying to translate that into paleoecology,” she said. “It’s difficult because there are so many processes that go into fossilization. It’s a very delicate process, and the quality of the preservation is important in identification. It gives us a skewed view of the diversity of that environment at that time.”

Robison is using modern indices—including the Shannon Index and Simpson’s Index—to evaluate what the environment was like when the fossils were deposited, compare it to today’s environment, and understand how things have changed over time. Participating in the research lab has helped Robison develop as a scientist.

“It helped me form and grow my mind as a scientist and think like a scientist,” she said. “What question do I want to answer? How will I go about doing that? How will I communicate that effectively?”

Robison is taking her research a step further by working with Coastal Georgia alum James Hutchinson, who is helping her analyze how the indices function.

“He’s helping me figure out what other math tools to use to interpret the data,” Robison said. “So, I’m taking an interdisciplinary approach to the research as well.”

Victorya Adams, a senior, is new to the Microfossil Lab this semester. She has a broad range of interests and learned about the lab from Dr. Robin McLachlan, assistant professor of geology, in a historical geology course. Currently, Adams is sorting through sediment in search of microfossils. At the end of the semester, she will present her findings at the upcoming Coastal Science Symposium. So far, Adams has found fossils of fish scales, mollusks, frogs, and gar.

“My side project is to review all the literature we have of the fossils found at the quarry and upload that information to the Paleobiology Database,” Adams said. “It’s like an international record of fossils found all over the world. We’re trying to get the quarry on there so that other people can see what we have.”

Adams already holds a bachelor’s degree in English and creative writing. She is pursuing a second bachelor’s in environmental science with a concentration in environmental studies. Her goal is to combine her two degrees and pursue a career in environmental writing.

Junior Olivia Fambrough is sorting through sediment for fish scales. Many of the present-day fish species along the Georgia coast also existed during the Pleistocene, like the gar and red drum. The lab has a large number of gar scales, and Fambrough is helping broaden the fish category.

“We’re looking at otoliths, which are calcium carbonate bones found in fish skulls. We just identified our first one, and it was from a red drum. That was very exciting,” Fambrough said.

Fossilized fish scales are usually orange, but otoliths resemble stones and can be easily overlooked. Eddie Leonard, of the Coastal Resources Division of the Georgia Department of Natural Resources, identified an otolith in the lab’s collection. Since then, Fambrough has been reviewing specimens to identify more otoliths.

This is Fambrough’s second semester in the lab. She’s not only enjoying her research, but also seeing the progress of other students’ projects.

“Here at the College of Coastal Georgia, we are fortunate to have a lot of research opportunities,” she said. “I was talking to Dr. McLachlan about research opportunities, and she mentioned the Microfossil Lab. It sounded interesting, so I decided to join.”

While searching for fish fossils, Fambrough was surprised by how well preserved the fish scales were from the Late Pleistocene.

“You would be shocked to find a whole scale, especially with how thin and fragile they are. When I first started, I was sorting through sediment and wondered what these flakes were—they were amber-colored,” Fambrough said. “I asked what they were, and the professors said they were fragmented fish scales. But we have a good collection of them. I’m definitely excited to continue with the fossil lab and build on what we have here.”

Fambrough is majoring in environmental science with a concentration in marine science and is considering a career in fisheries. She initially took geology courses as a graduation requirement, but has since taken more due to her growing interest and experience in the lab.

Sophomore Cal Ostertag has taken on the leadership role of setting up and learning the program’s new ground-penetrating radar system (GPR). The GPR, which resembles a push lawnmower, allows users to image soil layers and detect large objects without digging. It sends back an image of the upper profile of objects beneath the ground, providing a top-down view.

“In the Late Pleistocene, there was an ancient riverbed, and we can see that through core samples. We want to learn if we can see that on the radar too, so we can map it,” Ostertag said. “We’ve been collaborating with UNG, using their existing data for comparison. We can see how the environment changed over time and how the river sand turned into fossiliferous rock, then regular soil.”

Ostertag is eager to visit the quarry for the first time. He hopes to break ground and help dig to see the sediment layers for himself. Working in the fossil lab is a dream come true for him. He originally thought fossil work would be just a fun hobby, but realized there are real-world applications.

“I want to do bathymetric mapping. Bathymetric mapping means mapping the ocean floor with sonar. It’s very similar and adjacent to what you use GPR for—mapping what you can’t see,” he said. “It will look good on a résumé to have experience with GPR.”

Bathymetrists—also known as marine geologists and oceanographers—are known for finding shipwrecks and shipping containers. Ostertag shared that much of the ocean is not mapped to current standards, and some research still relies on data from the 1880s.

“If you look at a map for marine traffic, there are no empty spaces,” he said. “However, there are only a handful of research ships with mapping technology.”

Ostertag hopes to get aboard a research ship next summer. In the meantime, his project involves learning how to use the GPR software and process the visual data.

Other research students in the Microfossil Lab include Cierra Agistoleis and Paige Starbuck. Agistoleis identified fish and plant microfossils, such as drum teeth and plant vascular tissue. She concluded that the presence of drum teeth indicates a transition from freshwater to brackish water in the area, and the vascular plant tissues point to a variety of vegetation in the ecosystem. Starbuck identified small mammal fossils, most notably, rodent fossils. She concluded that rodents and small mammals functioned steadily throughout the paleoenvironment.

The Microfossil Research Lab has at least 66 unique identifications for animals and 207 specimens. Perhaps just as notable is the growing number of students gaining a deeper understanding of Earth’s ancient history and an appreciation for the work that fuels scientific discovery. Through hands-on experience, they are developing skills that extend far beyond the microscope—skills in observation, analysis, and curiosity-driven research that will serve them well in their scientific pursuits.

This is the first part of a two-article series about the Microfossil Research Lab. The next will be a more in-depth story about Clark Quarry.