Paleontologists are very lucky. Deserts often preserve fossils better than anywhere else on the planet. The desertification of places like the Gobi and Sahara deserts enabled fossilization. Two hundred million years ago, dinosaurs dominated the then rain forests and wet tropics. Back then, the earth’s tectonic plates formed one super-continental landmass called Pangaea, separated into two parts by a body of water called Tethys Sea. The earth was hot during the Triassic and became tropical and sub-tropical during the Jurassic and Cretaceous. It makes me wonder, what dinosaurs lived in the desert?
In general, desert terrains during the Jurassic existed in places like the Western US, which was more of a coastal desert. Carnivorous dinosaurs like Allosaurs, Troodons, and Dromaeosaurs lived there. Many herbivorous dinosaurs groups like sauropods and hadrosaurs lived there and possibly migrated to habitats with more vegetation.
Read on to take a deeper look at desert regions that exist now and sandy deserts that existed millions of years ago. I’ll also list a few of my favorite dinosaurs that, based on fossil evidence, suggests they lived in the desert.
Let’s get started.
Deserts like the Gobi and Sahara Were Not Deserts Millions of Years Ago
Paleontologists are very lucky. The desertification of places like the Gobi and Sahara deserts enabled fossilization.
Two hundred million years ago, dinosaurs dominated the then rain forests and wet tropics. Back then, the earth’s tectonic plates formed one super-continental landmass called Pangaea.
The gigantic Pangaea landmass split into the multiple continents we have today over millions of years. The continental shift spread diverse dinosaurian species globally, and these regions hosted dinosaurs until the K-T extinction event.
When the asteroid impacted earth, it lodged dust high into the atmosphere, and terrestrial dinosaurs got buried alive.
For about 70 million years, these rainforests preserved the remains of prehistoric creatures. Fortunately for paleontologists, desertification hit the Gobi and the Sahara before human civilization emerged. (Source)
Just 6,000 years ago, the Sahara desert was still a lush, tropical rainforest. It was always wet and warm during the Jurassic era, much like the then densely-forested Gobi Desert.
Desertification hit the former rainforest regions as the earth’s axis shifted and our planet changed its rotational angle. The rivers and lakes that covered the prehistoric Gobi and Sahara got swallowed.
Desertification converted rainforests around the Sahara and Gobi regions inhabitable deserts. Human civilizations began 6000 years ago, and we found the desertification process at an advanced stage. Thus, people did not disrupt ancient dinosaur tombs.
Flash forward to contemporary times. Paleontologists are finding an abundance of fossils from rare or newly-discovered dinosaurian species. For instance, scientists can better connect the dots between modern birds and prehistoric dinosaurs.
For example, the Greek meaning of Oviraptors is egg thief. Researchers misunderstood Oviraptors to be carnivorous dinosaurs that stole and ate the eggs of other dinosaurs. However, a paleontological expedition into the Gobi desert unearthed the nesting habits of these predators.
It emerged that much like modern-day birds, Oviraptors nested their eggs and gave parental care to their offspring. The knowledge surfaced after American paleontologists discovered a fossilized Oviraptor, its nest, and 12 eggs. (Source)
The Triassic and Jurassic Periods Had Hot, Desert-Like Climates and Landscapes – What Dinosaurs Lived There?
The Mesozoic Era was the Age of the Reptiles. It started with the Triassic Period, which lasted between 251-199 million years ago. The Triassic Period came immediately after the Great Dying of the Permian Extinction.
The dry climate and hot summers were common throughout this period. The seasons were most extreme towards the center of the supercontinent, and winds couldn’t blow precipitation far enough inland to reach the terrible center of Pangaea.
There were no polar ice caps and monsoon winds to regulate four transitional seasons as they do today.
As the Triassic Period came to an end, the Tethys Seafloor started spreading. Pangaea continuously split into Laurasia and Gondwana between the Late Triassic and Early Jurassic Period.
YouTube Video About Dinosaurs and Bone Remains in Gobi Desert
The Jurassic Period came after the Triassic Period, and it lasted between 145.5 and 200 million years ago. This period was mostly warm and wet, giving rise to lush vegetation and the explosion of dinosaur diversity. (Source)
Popular Sauropods with gigantism appeared during this period.
Earth became less desert-like, becoming subtropical and humid. Forests comprised of ferns, cycad, and conifers, but flowering plants had not yet evolved. During this period, the split of Pangaea was finalized, and the two subcontinents also splinted.
Laurasia split up into Eurasia and North America. Gondwana followed suit, breaking up into:
• South America
Former deserts transformed into lush vegetation for dinosaurian species. The suitable environment catalyzed the evolution of giant Sauropods like the 85-foot long Brachiosaurus.
However, the transformation was gradual. For example, Gondwana didn’t finish splitting into favorable continents until the mid-Jurassic period.
Desert Dwellers Based on Fossil Evidence
Although not all dinosaurs were suited for tropical climates, the ones that existed in deserts are some of the best-studied and most popularized members of their families.
Here is a list of five to eight common dinosaurs whose fossils have been found in sandy terrain, starting with one of my favorites!
Allosaurus (Allosauridae, Theropoda)
The Jurassic Period was one of the most famous periods for the rise of the carnivorous dinosaurs. Allosaurus was a large, aggressive predator stalked through North America and Europe during the late Jurassic period.
Allosaurus was smaller than Tyrannosaurus rex but larger than Utahraptor and Carcharodontosaurus (some scientists even consider it an early relative of T-Rex). Thus, it’s often depicted as a hunter who charged its prey with its sickle-shaped jaws open.
To date, the most famous Allosaurus specimen is a complete skeleton called “Big Al;” Allosaurus fragilis was discovered in 1877 by Oramel W. Lucas and has been on display at the Peabody Museum of Natural History in New Haven, Connecticut, for over 130 years! (Source)
Allosaurus had more than 70 teeth that were serrated and razor-like. But despite its menacing appearance, it has only been preyed upon once by another dinosaur – Ornithomimus edmontonicus.
Ornithomimids were small dinosaurs with long legs who often scavenged the corpses left behind from larger predators like Utahraptor.
Struthiomimus (Ornithomimidae, Theropoda)
A smaller, slower relative of Allosaurus living alongside it, the Struthiomimus was a common scavenger.
Struthiomimids lived throughout the entire duration of the Late Cretaceous period in North America and Mongolia. In Western North America, fossils have been found in what used to be considered a vast coastal desert.
Struthiomimids had a similar skeletal structure to Allosaurus but lacked long arms and were not equipped with powerful jaws or claws. Instead, this ostrich-like dinosaur was armed with short forearms, which is used for digging up invertebrates. This animal’s name means “ostrich mimic.”
Dromaeosaurus (Dromaeosauridae, Theropoda)
The dromaeosaurs are known by the moniker “raptor”; one is a small East Asian bird called the Red-Footed Falconet (Daptrius americanus,) while the other is represented by birds such as hawks and eagles!
A dromaeosaurid, Dromaeosaurus was a small predator that lived in Utah during the Early Cretaceous period. DMNH 5060 (also known as “Jim”), found in 1982 by Dr. James Ostrom, is one of the most famous dromaeosaurs and even made an appearance in Jurassic Park III!
Dromaeosaurus had a similar skeletal structure to its relative Allosaurus but did not have sickle-shaped jaws. Instead, this carnivore had serrated teeth that were specialized for slashing prey.
It wasn’t very fast, though – it has been estimated that these dinosaurs could only reach speeds between 15-25 mph! This slowness might have been counteracted by the animal’s size, which was just less than six feet long!
Troodon (Troodontidae, Theropoda)
The discovery of a new troodontid species in 2012 is changing what scientists know about this dinosaur!
The Troodon formosus lived in the Late Cretaceous period on an island archipelago called Laramidia. Laramidia used to be a part of North America but gradually broke off from the mainland and formed its own landmass.
Because of this isolation, many dinosaurs evolved to become different physically from their mainland cousins and behaviorally distinct. One example is that Troodon had longer and thinner jaws than other dromaeosaurids.
Troodon had large eyes, and its brain was larger than the brain of Dromaeosaurus, which suggests it may have also been smarter! It may have been built for speed as well – its legs were long and slender, with lightweight construction. (Source)
It also has been suggested that Troodon is not only smart but also emotional – several fossilized specimens have developed lesions on their teeth from biting into poisonous prey or plants!
I have often thought of the desert climates that must have been around during the Jurassic period. It was harsh, hot, dry, and possibly volcanoes scattered over the land. As the world turned, more sub-tropical and conifer forests took hold, the large continents broke up and formed island archipelagos in the Cretaceous. How much of the land was desert at that time, and I wonder if dinosaurs preferred the desert climates? Perhaps one answer is the migration of dinosaurs, which some scientists think was possible. In this case, herbivorous dinosaurs would travel over any terrain looking for more plants to eat, and carnivorous dinosaurs would follow.
The current-day deserts like the Gobi of China and Mongolia most likely still hold many fossilized skeletons, giving further insight into dinosaur habitats. Thanks to the desertification millions of years ago, we have those fossil records!