Unearthing History: Decatur native living paleontological dream

Oct. 30—Excitement filled Drew Gentry's voice as he talked — albeit vaguely — about his latest excavation.

"A wife and husband in south Alabama have found something truly remarkable. It's one of only a handful of these found in North America. It is a gigantic specimen large enough to require the help from multiple agencies and heavy machinery. And, sadly, that's about all I can say until the specimen is safely removed," Gentry said.

The excavation marks the latest paleontological adventure for the 37-year-old Gentry, one of the world's authorities on fossil turtles in Alabama.

Gentry, who has named three species of turtles that date back tens of millions of years to the age of the dinosaurs, developed a love for fossils while studying the limestone gravel behind his childhood home in Decatur.

Just ask his mother.

"When he was about 4 or 5 years old, he started digging through the rocks in the alley. He noticed there was stuff in the rocks. He found rocks with shells in them and asked why there were shells in the rocks since we weren't near the ocean," Lynn Gentry said.

That curiosity extended to school, where he filled his pockets with crinoid fossils found at the playground during recess, and to the baseball field, where he played in the outfield.

"You'd look out in the field and he would be bent down digging for rocks. He never caught a ball out there, but he found fossils," Lynn Gentry said.

Freshwater turtle

Drew Gentry, a Decatur High graduate, recently made headlines for leading the research on a previously unknown species of freshwater turtle that roamed the state 83 million years ago.

Collected in south Alabama in the spring of 1985 — around the same time Gentry was born — the specimen sat in the University of Alabama Museum of Natural History's collections area for 25 years.

"It was in a fossil warehouse and not on public display because no one came along that was an expert in fossil turtles and knew how special it was. At one point the specimen was just labeled 'turtle' and that was as specific as it got," Gentry said.

That was until James Parham, a specialist in fossil turtles, became the museum's curator of paleontology in 2010. When he saw the specimen, Parham recognized it as a macrobaenid — an extinct family of turtle.

"He did work on macrobaenids during his Ph.D. research at UC Berkley. He knew macrobaenids had never been discovered in Alabama and he knew what he saw was unlike any macrobaenid that had ever been described," Gentry said.

When Parham, who started the preliminary background reading and comparative work on the fossil, accepted a professorship at the University of California Fullerton, he took the turtle, on loan from the museum, to California to continue the research.

In 2018, after Gentry completed his doctorate, Parham, who served as a member of Gentry's graduate research committee, asked Gentry to take the lead on the project and shipped the specimen back to Alabama.

During the next four years, Gentry studied research articles from the past 70 years about macrobaenids, learned about their anatomy, ecology and distribution, described the specimen's osteology so future scientists can compare it to what they find, reviewed all of the occurrences of macrobaenids across North America and determined where the specimen was found.

To determine where it was found, Gentry sent a sample of soil adhered to the fossil to the U.S. Geological Survey.

"It was sort of like conducting paleontological forensics," Gentry said. "They looked at microfossils embedded in the soil and told us which layer of rock it came from. Since we know what parts of the state (where) rocks of that age are exposed and where we had a record of freshwater fossils, we narrowed the site down to south central or southwestern Alabama."

In the research published in the "Anatomical Record" in August, Gentry named the specimen Appalachemys ebersolei in honor of Jun Ebersole — the man who sparked Gentry's interest in turtles.

Gentry, who graduated from New Mexico State University and became the first paleontology graduate student at UAB's biology department, crossed paths with Ebersole, the director of paleontology collections at Birmingham's McWane Science Center, which contains hundreds of thousands of specimens, in 2012.

"Dr. Ebersole said I could study the fossils at McWane for a research project. I told him I had no idea where to start," Gentry said. "He laid out three major projects: small Ice Age mammals, fossil fish and fossil sea turtles from the Cretaceous Period. I chose turtles because, even though they aren't dinosaurs, they are reptiles and lived during the same period as the dinosaurs."

New species

Sea turtles, Gentry discovered, proved very interesting and productive.

"Fossil sea turtles are a very understudied group of animals from Alabama, and Alabama just so happens to be the best place on Earth to find the fossils of late Cretaceous marine turtles," Gentry said. "One of the wonderful things about Alabama is we are, without question, one of the most fossil-rich areas in all of the United States and probably in most of North America."

In 2018, while a doctoral student, Gentry named his first species Peritresius Martin after George Martin, a retired U.S. Department of Agriculture soil scientist and avid fossil collector who found the fossils in Lowndes County and donated them to the Alabama Museum of Natural History. The turtle with a 3- to 4-foot-long shell lived 70-73 million years ago.

A year later, Gentry was the lead author in a study revealing a new genus and species of turtle that lived 75 million years ago. He named the new species with a 5-foot-long shell Asmodochelys parahami after Parham.

"I've named three new species, but that's just the nature of doing paleontology in Alabama. You're likely to find something that has not been described in scientific literature because Alabama has this fossil gold mine and only a handful of practicing paleontologists doing research on Alabama fossils," Gentry said.

Scientists credit Alabama's richness in fossils to the state's age range and connection with water.

"At one point or another over the last half billion years, some part of Alabama has been at the bottom of the ocean and fossils preserve relatively well in marine environments. We also have a unique geology. In the north part, you have the oldest rocks in Alabama at half a billion years old. The rocks steadily get younger as you go south. In Mobile, the rocks are only a couple of million years old," said Gentry, who teaches biology at the Alabama School of Mathematics and Science in Mobile.

Along with the upcoming excavation and teaching, Gentry is working with students to describe and name potential new species of fossil turtles found in Alabama.

'It never slows down'

"This is paleontology in Alabama. It never slows down. There are always remarkable fossils to uncover and research," Gentry said.

By participating in excavations and studying fossils, Gentry is fulfilling his childhood dream — a dream many people questioned.

"Ever since I learned what the word 'paleontologist' meant, I knew that was what I wanted to be. While most kids wanted to be an astronaut, firefighter or dinosaur, I wanted to be a paleontologist," Gentry said. "Many people assumed it was a passing childhood interest. It wasn't until I got to graduate school to study paleontology that people were like, 'I think he's really going to do this.'"

Two people who never questioned his dream were his parents Lynn Gentry and the late Phillip Gentry.

"The people that never told me paleontology was not a viable career and fossil collecting was only a hobby, were my parents. They were always very supportive of my interest and took me all over the place to collect fossils," Gentry said.

After watching an episode of "Discovering Alabama" where Doug Phillips collected shark teeth from a hillside, Phillip Gentry arranged for his son to visit the site.

"My father spent no telling how many hours tracking down where this place was and contacted the people that owned the property so we could collect fossils there. They were always very supportive," Gentry said.

In 1997, after hearing of a University of Alabama in Huntsville biology professor who conducted dinosaur digs in North Dakota, Phillip Gentry arranged for his son to accompany the research group.

"My father worked at the university and covered stories out of the biology department. He got to know Dr. William Garstka, who was a vertebrate paleontologist, and, somehow, convinced him to let me, a 12-year-old kid, tag along," Gentry said.

That summer, Phillip and Drew Gentry spent 2 1/2 weeks in the Badlands on an expedition. Among Drew Gentry's finds was a finger bone from a Tyrannosaurus rex and a juvenile triceratops femur measuring 3 1/2 feet long and weighing 100 pounds. The femur currently sits in the McWane Science Center.

"When Drew came back with the dinosaur bone, I figured he'd be doing this for a while. Even when people questioned him, he followed his heart," Lynn Gentry said. "I am so very proud of him."

— cgodbey@decaturdaily.com or 256-340-2441. Twitter @DecaturLiving.