Experts discovered the remains of a 100-million-year-old “river monster” that proves dinosaurs once lived underwater. In fact, it’s the first time that they have found conclusive evidence that proves some dinosaurs lived, swam, and hunted beneath the water.
The remains were found in the now-barren wilderness of the Saharan desert but it was not always this way as 100 million years ago it contained waterways and rivers. Researchers began excavating the area in southern Morocco back in 2015 and by 2018 they had uncovered a nearly-complete well-preserved skeleton of the dinosaur’s tail. The species belongs to the theropod group which the Tyrannosaurus rex is a part of.
The dinosaur, which has been named Spinosaurus aegyptiacus, had razor-sharp six-inch long cone-shaped teeth that it used to capture and hold onto its prey. The nostrils were located on the back portion of the head and its snout was quite similar to a crocodile’s. It had very dense bones as well as large flat feet that were more than likely webbed.
Even though it was only a juvenile when it died, it still measured 35 feet long and weighed approximately 4 tonnes. Fully grown adults could have measured as long as 50 feet and weighed up to 20 tonnes. While the adults had no known predators, the juveniles could have been attacked by giant prehistoric crocodiles and fish. In fact, the location in which the skeleton was found has been nicknamed the “river of death” by the researchers. Numerous groups of reptiles inhabited the waters (such as the ichthyosaurs), but this is the first ever evidence of a dinosaur living underwater.
And based on the evidence the researchers found, the Spinosaurus aegyptiacus thrived in the ancient Saharan waters. As for its unique tail, the species had two-foot long struts located on the main vertebrae which made its tail into the shape of a paddle that moved from side to side. This is quite interesting as other therapods that lived on land had a stiff tail that tapered off at the end.
Dr. David Unwin, who is a Reader in Palaeobiology at the University of Leicester and was also involved with the research (their study can be read here), explained this further, “The Spinosaurus’ fin-like tail is a game changing discovery for us that fundamentally alters our understanding of how this dinosaur lived and hunted – it was actually a ‘river-monster’”. “As well as its tail, many other features of this dinosaur, such as the high position of the nostrils, heavy bones, short legs, and paddle-like feet point to a life spent in the water rather than on land,” he said, adding, “Not only did dinosaurs dominate the land and take to the air as birds, they even went back into the water and became the top predators there as well.” A picture of the excavation site can be seen here.