News Release

UNC geologist, students to unveil 221 million-year-old top N.C. fossil

Peer-Reviewed Publication

University of North Carolina at Chapel Hill

NEWS CHAPEL HILL – Having re-assembled the equivalent of a 221 million-year-old jigsaw puzzle, Dr. Joseph Carter and his geology students at the University of North Carolina at Chapel Hill will display their work to the public beginning Feb. 27. What they have done, Carter said, is to painstakingly piece together the large skeleton of an extinct reptile known as a rauisuchian, which once roamed what is now North Carolina and ate whatever unlucky creatures crossed its path.

The partial skeleton, which includes the skull, will be erected in Room 039 of the James M. Johnston Center for Undergraduate Excellence, housed in the Graham Memorial Building. It will be unveiled at 4 p.m.

Former UNC undergraduates Brian Coffey and Marco Brewer discovered the fossil in an undisclosed east-central N.C. site, making what the professor called “the most spectacular and important fossil find in North Carolina history.” Raking his pick along the ground to expose fresh rock in 1995, Brewer impaled the ankle bone of the prehistoric creature lying just below the surface of an ancient lake or river bed.

“Brian brought the bone to me and asked if it was anything interesting,” Carter said. “I was very curious because I’d never seen anything from the Triassic of North Carolina with ankle bones joined together. We went back to look more carefully the next day and found and removed a lot more material.”

Carter and students have been working on the remains ever since, including for the past three years, freshmen enrolled in UNC’s first-year seminar program. Other top paleontologists quickly agreed to help out too.

“About a year after the initial discovery, we started realizing during the cleaning process that we had something really special,” the geologist said. “It was like a series of Christmas presents that just kept getting bigger and bigger.”

The late-Triassic Period animal turned out to be a new species and probably a new genus of rauisuchian, a reptile that was evolutionarily half way between dinosaurs and crocodiles, Carter said. Its kind died out just after the first dinosaurs appeared. “Unlike dinosaurs, which walked on their toes, these guys walked partially upright on their heels and toes like humans do and dominated the world until the dinosaurs took over,” he said. “They dominated the early dinosaurs too, but then went extinct, possibly because of climate change or a global catastrophe such as an asteroid or comet impact. Dinosaurs then got bigger, dominated mammals and went extinct themselves about 65 million years ago.”

Because it has not been published, Carter cannot disclose the proposed scientific name of the new reptile. He said it will be named to honor Allison Chambers, the late champion of N.C. fossils. The creature -- the major predator on the U.S. East Coast -- was 10 to 11 feet long and weighed about 1,500 pounds. It resembled a large, long-legged alligator.

“This guy was built something like a football player with a thick neck, powerful shoulders and long arms,” the geologist said. “Unique for rauisuchians, it also had a thumb hooked into the base of his second finger to make a powerful pincer-like grip. When you put those together, you’ve got a really super predator.”

The professor and his students also found “a whole suite of bones” where the reptile’s stomach would have been, Carter said. Included was another new mammal-like reptile, which Drs. Hans-Dieter Sues of the Royal Ontario Museum, Paul Olsen of Columbia University and Carter have named Plinthogomphodon herpetairus.

Also in the stomach were armor plates from a 2- to 3-foot long creature called Aetosarus that had a pointed nose and tail and looked like “a little streamlined armadillo.” Beneath the larger animal were remains of still another crocodile-like reptile known as a sphenosuchian. That creature, now being studied in Canada, walked on long, spindly legs like a dog’s.

“We found it beneath the rauisuchian’s left leg like it had been pinned down,” Carter said. “We suspect it was killed by the rauisuchian because there are tooth crushing marks on its neck. The larger animal then died and fell on top of its prey.”

The superb specimen is the most complete sphenosuchian from the late Triassic Period ever found, he said. Previously, the most famous North American rauisuchian, Postosuchus, was found near Lubbock, Texas. The degree of fusion in the back bones of the new species showed it to be relatively young when it died, possibly between 10 and 13 years. It appears to have had a history of broken toes.

“This discovery, the first substantial find of a rauisuchian on the East Coast of North America, was in a way a remarkable fluke,” the geologist said. “I’ve been going to these areas for 25 years, and the most I’ve found are little bits and pieces of bones. Other faculty here have been going to the same counties for 30 or 40 years, and it’s been the same with them.”


Note: Carter can be reached at (919) 962-0685.
Contact: David Williamson, (919) 962-8596

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