Dinosaurs lived all over the world, but their fossilized remains are not easy to find, or even, sometimes, to recognize. A desert surface free from vegetation, or the side of an eroding cliff, may expose fossils of dinosaurs buried in sediment millions of years ago. The remains may be incomplete, with many or most of the bones washed away by an ancient river. However, in nearly 200 years of painstaking exploration, palaeontologists have located many exciting dinosaur sites.
The distribution of dinosaur discoveries can give a misleading impression about the distribution of the dinosaurs themselves. Dinosaurs have not been excavated in all the places they lived in. There are many historical and political reasons for this – perhaps a team cannot reach an area because of war or because they are not welcome in a particular country. Also, the layout of the continents has changed since the Mesozoic Era – so we cannot tell exactly how many dinosaurs lived where.
In the Midwest and foothills of the Rocky Mountains are perhaps the most famous sites of all. In the Bone Wars of the 1880s, two US palaeontologists, Edward Drinker Cope and Charles Othniel Marsh, competed to find bigger and better dinosaur remains for the museums they represented. The result was that over a period of only 20 years, an incredible 150 new types of dinosaur were discovered.
Argentina and southern Brazil are the current hotbeds of palaeontological activity. The work being done there is showing what dinosaur life was like in the Cretaceous on the great southern continent of Gondwana, which included today’s Africa and India. The fossil remains found in South America include some of the oldest – Eoraptor – as well as the largest of all the dinosaurs – the titanosaurs.
The first dinosaur remains to be discovered and correctly identified were in various parts of England in the 1820s. The long tradition of discovery is continued today on the Isle of Wight, off the south coast. Early Cretaceous theropods such as Megalosaurus and huge sauropods such as Diplodocus – dinosaurs previously associated with North America – have recently been excavated there.
For more than 100 years, Africa has been a key destination for dinosaur-hunters. Deserts are ideal places to look for fossils and the Sahara Desert has revealed many. The first finds in Africa were made by expeditions from Germany before World War I began in 1914. Today, most of the excavations are being carried out in Morocco and Niger, and finds include the discovery of one of the largest carnivores ever found, Carcharodontosaurus.
In the 1920s, expeditions led by the American Roy Chapman Andrews found dinosaur remains in the Gobi Desert in Mongolia. The original discoveries were made by accident – the first expedition was actually looking for the remains of early humans. The most exciting discoveries were the first dinosaur nests and eggs to be unearthed. Fossils are still being discovered there, mostly by teams from China, America, and Eastern Europe.
There have been several dinosaur discoveries in Australia, but the most important were made in the 1970s. The site, on the coast of Victoria, has since been named Dinosaur Cove. The finds there show that ornithopods were abundant in this area in the Cretaceous, when the land was within the Antarctic Circle. The remains of these dinosaurs show that they had adapted to long Antarctic winters of intense cold.
It was thought that dinosaurs had lived on every continent except Antarctica. However, in 1986, the first fossil was exposed beneath the ice. In 1991, several carnivores, including the crested Cryolophosaurus, were found on Mount Kirkpatrick. There have been other finds since. In early Jurassic times, when these animals lived, Antarctica was part of the supercontinent Pangaea, and was much closer to the Equator.