North Carolina, known for its coastal plains and Appalachian mountains, holds a rich, though elusive, dinosaur history within its ancient rocks. The fossil record here presents a unique challenge to paleontologists, differing significantly from the vast bonebeds of the American West. Complete skeletons are exceedingly rare, but the recovered evidence paints a picture of a diverse prehistoric ecosystem. Understanding the state’s deep geological past and specific preservation conditions is key to exploring this localized paleontology.
The Mesozoic Landscape of North Carolina
The landscape of North Carolina during the Mesozoic Era was dramatically different from today, explaining the unique nature of its fossil deposits. During the Triassic Period, approximately 230 million years ago, the Piedmont region was marked by active rift basins—long, narrow valleys formed as the supercontinent Pangea began to split apart. These basins, such as the Deep River Basin, collected terrestrial sediments, preserving some of the earliest evidence of dinosaurs as trackways and isolated teeth.
By the Cretaceous Period (100 to 66 million years ago), the environment shifted considerably, with much of the eastern third of the state submerged or near a shallow sea. The Atlantic Coastal Plain formed during this time, resulting in the deposition of marine and estuarine sediments. This coastal setting meant that many dinosaur remains were washed out to sea after death, leading to fragmented bones mixed with marine fossils. The shifting shoreline and brackish water created a challenging environment for fossil preservation compared to the inland river systems of the West.
Identifying the Dinosaur Residents
The specific types of dinosaurs identified largely come from the Late Cretaceous sediments of the Coastal Plain, particularly within the Black Creek Group. One frequently mentioned, though fragmentary, find is Hypsibema crassicauda, a large, duck-billed dinosaur belonging to the Hadrosaurs. This classification is based on massive tail vertebrae and limb fragments found in Sampson County, though the remains are so incomplete that its status as a distinct species is uncertain.
Other ornithopods, or bird-hipped herbivores, are represented by teeth and bone fragments from related Hadrosaur groups like Hadrosaurus. Carnivorous dinosaurs are also present, indicated by isolated teeth with distinct serrations and shapes. These include evidence of tyrannosauroids, large theropods that may be related to the genus Dryptosaurus. Smaller, more agile dinosaurs include Ornithomimids (ostrich-like dinosaurs) and Dromaeosaurids (raptors), indicating the presence of swift hunters. Additionally, the first evidence of a Leptoceratopsid, a small, primitive horned dinosaur previously unknown from eastern North America, was identified from a jaw fragment in the state.
Understanding the Fossil Evidence
Paleontologists have pieced together this history using evidence often overlooked in areas with more complete skeletons. The primary body fossils are isolated teeth and bone fragments, which are far more common than articulated skeletons. Teeth are especially valuable because their morphology—the shape, size, and wear patterns—is highly distinctive. This allows identification of a dinosaur down to the family or genus level.
The Black Creek Group, encompassing formations like the Tar Heel Formation, is the main source of these Late Cretaceous body fossils. These deposits are primarily estuarine, meaning terrestrial dinosaur remains were often preserved alongside marine creatures like sharks and mosasaurs. This unique mixing supports the “bloat-and-float” hypothesis, where dinosaur carcasses drifted out to sea before sinking and becoming fossilized.
Beyond body parts, trace fossils (ichnofossils) provide some of the oldest evidence of dinosaurs in the state. Footprints like Grallator and Atreipus were left in the muds of the Triassic rift basins in the Piedmont region. These ancient trackways, found in places like the Solite Quarry, confirm that early bipedal and quadrupedal dinosaurs walked across the landscape long before the Cretaceous era. The ongoing study of these fragmented remains continues to expand the understanding of the diverse dinosaur communities that inhabited this side of the continent.