Dinosaur fossils are found all over the world, but a great many have been discovered in North America. Many paleontologists and biologists have devoted whole careers to studying North American fossils because of the sheer number that have become available over the years.
Dinosaur populations were not necessarily larger in North America than in other parts of the world. In fact, North America did not even exist, as we know it, millions of years ago. Most people know that the continents were fused together into one large land mass called Pangea. As the eons went by, the continents drifted to be where they are today. The fact that some fossils common to North America have also been found in other parts of the world is used as evidence for continental drift. Conditions throughout much of North America just make it easier to find fossils here.
The Morrison Formation is one such area. It covers a large part of the Western U.S., including Colorado, Wyoming, Kansas, Montana, among others, and is a collection of rocks that date back to the Jurassic period (150 million years ago). The Morrison Formation is one of the largest sources for ancient fossils in the world. Hundreds of different species of dinosaurs, mammals, insects, and plants from the Jurassic period have been fossilized in the Morrison Formation.
Some of the dinosaurs discovered at the Morrison Formation include the Apatosaurus (the dinosaur formerly known as Brontosaurus), Stegosaurus, and Supersaurus, which as its name suggests, is one of the largest dinosaurs ever discovered. It is believed that more than 75% of the Morrison Formation still remains undiscovered, buried under the Rocky Mountains and other inaccessible rock formations.
For fans of dinosaurs, when talking about species most associated with North America, the Utahraptor and Utahceratops spring to mind, because both are named after the state of Utah, where they were discovered. The Utahraptor is especially notable because it is the largest raptor dinosaur found so far. It likely grew over 8 feet tall (2.4 meters) and would have dwarfed a grown man. Most other raptors, including Velociraptors, were about the height of a large dog. Movie fans may remember the large Velociraptors stalking the visitors of Jurassic Park in the 1993 Steven Spielberg film. At the beginning of the story, their fossils are discovered in Montana. In reality, a raptor that large found in that part of the country would have more than likely been the Utahraptor!
It is impossible to list all of the ancient species discovered in North America. They date back to the Jurassic Period and other periods, including the Triassic and Cretaceous. Many important discoveries about the lives of dinosaurs are attributed to discoveries in the U.S., Canada, and Mexico. In fact, the Cretaceous–Paleogene extinction event, the event that is believed to have wiped out the dinosaurs occurred in the Gulf of Mexico. It is thought that a massive asteroid or comet collided with the earth in this area, which set off a global cloud of gas and dust that created winter like conditions around the world and led to the mass extinction of 75% of all plant and animal species on Earth. Most of the large animals died during that extinction event, paving the way for the Cenozoic era, the Age of the Mammals.
Originally from Columbus, Ohio, Ani is a fan of exploring new places through photography and the local cuisine. After earning her BFA in photography from NYU and gaining communications experience at International Planned Parenthood Federation, she joined InterExchange in 2012, and worked as the Marketing Producer until 2016.