Two Hundred Years of Dinosaur Discoveries: How the Fossil Record Expanded from Europe and North America to the Globe

Sep 28

6 min read

In 1824, the British geologist William Buckland formally described and named Megalosaurus bucklandii, making it the first dinosaur to receive a scientific name. At the time, the concept of dinosaurs as a distinct taxonomic group did not yet exist; it was not until 1842 that Richard Owen established Dinosauria. Two centuries later, our understanding of the dinosaur world has changed enormously. By the end of 2025, a study compiling 200 years of dinosaur naming records recognized 1,259 reliably known species of non-avian dinosaurs, including 465 theropods (Theropoda), 366 sauropodomorphs (Sauropodomorpha), and 428 ornithischians (Ornithischia).

Only 58 species named during the 19th century are still regarded as valid today: 15 theropods, 18 sauropodomorphs, and 25 ornithischians. Of these, 55 came from Europe or the United States, while the remaining three sauropodomorphs were from Argentina, India, and South Africa. Many regions that are now major centers of dinosaur research were almost entirely absent from the scientific record at the time.

Whether dinosaur fossils are discovered depends first on whether rocks capable of preserving terrestrial animals are exposed at the surface, but it is also influenced by accessibility, collecting activity, research institutions, and scientific traditions. Nineteenth-century England provides a clear example. Although England is far smaller than France, substantially more dinosaur species from England named during that period remain valid today. One possible explanation lies in differences in the exposure of Mesozoic terrestrial sedimentary rocks between the two countries. The Paris Basin, one of France's major geological basins, was subjected to predominantly marine conditions from the Late Triassic onward, reducing the opportunities for terrestrial dinosaurs to enter the fossil record there.