Dinosaurs, or also called “terrible lizards”, are a fascinating group of animals that diversified on planet Earth approximately 230 million years ago. For more than 130 million years, it was the vertebrates that dominated the planet, but the Cretaceous-Paleogene mass extinction killed most dinosaur species. So if you’re wondering when dinosaurs became extinct, this was roughly 65 million years ago. Now, we mentioned the diversification of dinosaurs, but how many species of dinosaurs were there?
How many known species of dinosaurs existed
At the beginning of the 19th century, the first dinosaur fossils were found and since then paleontologists have not stopped discovering new species. Since the first fossil find, dinosaurs have caused great astonishment due to their impressive size and to this day, their skeletons continue to be the main attractions of museums. Thanks to the hard work of paleontologists, around 1,000 different species of dinosaurs have been identified , although it is estimated that there are as many other species to be found.
How many species of dinosaurs are believed to have existed
As we mentioned in the previous section, 1,000 species of dinosaurs are known, but it is considered that several species remain to be discovered. Scientific studies reported that there are approximately 1,700 to 1,900 species of dinosaurs .
Therefore, there are between 700 to 900 species of dinosaurs that remain to be discovered . This opens up two possibilities: fossils of these species may not yet have been found, or there may be no fossils of those species left on Earth.
Dinosaurs can be classified into two large taxonomic groups based on the structure of their hips. We will develop each of them below.
Saurischians, or lizard-hip dinosaurs , are those that had hip bones similar to the hip bones of current reptiles such as largaros and crocodiles. It is estimated that the species of this group of dinosaurs inhabited the Earth during the Mesozoic era. More precisely, they appeared during the Late Triassic (approximately 230 million years ago) and diversified during the Jurassic and Cretaceous. Within the diversification of the saurischians we can mention the theropods , which were characterized by their carnivorous diet and their limbs ending in 3 fingers, and the sauropods , whose diet was herbivorous and were quadruped.
The ornithischians or bird hip dinosaurs had an arrangement of the hip bones similar to the hip bones of modern birds. Like the saurischians, they inhabited the Earth during the Mesozoic era, from the Late Triassic (approximately 230 million years ago) to the Cretaceous (approximately 65 million years ago). All ornithischians were herbivores and some of them lived in herds.
We recommend that you also get to know the different species of dinosaurs by classifying their diet. Here you can read about herbivorous dinosaurs: names, types, characteristics and pictures and about carnivorous dinosaurs: names, types, characteristics and pictures .
We will dedicate this section to talking about the most important or popular dinosaurs that have been discovered. Below we will develop some of the species as an example.
The tyrannosaurus rex, possibly the most named dinosaur, is a species belonging to the group of saurischians that inhabited North America. It was a large carnivorous species that exceeded 10 meters in length and weighed more than 5 tons.
The genus Triceratops, belonging to the group of ornithischians, is made up of two species: T. horridus and T. prorsus. Both species were herbivorous and were distinguished by their large horned head that was proportionally larger than that of the rest of the terrestrial animals. Fossils of these species have been found in Canada and the United States.
In the history of dinosaurs, the velociraptor was the fastest of all dinosaurs, being able to run at a speed of 65 kilometers per hour thanks to its powerful hind legs. This quality made him a great hunter since he was a carnivore. Fossils of this species have been found in Central Asia.
Archeopteryx is a genus of dinosaurs that is considered the evolutionary transition between dinosaurs and modern birds. It had characteristics typical of dinosaurs such as jaws with strong teeth and a bony tail, but also peculiarities of birds such as small body size and large wings that allowed it to move certain distances. Its fossils have been found in North America.
Although it is not one of the best known species, the Patagotitan mayorum is the largest dinosaur that has been found so far. It is estimated that it was approximately 40 meters long and could reach a weight of 70 tons. It was discovered in the province of Chubut, in Argentine Patagonia.