The mighty Spinosaurus – who could grow up to fifteen meters in length – must have ruled the rivers in an inimitable way.
Until recently, dinosaurs were believed to be exclusively land animals. Until a recently published study made short work of that. Researchers had found a fin-like tail in Morocco that belonged to the predatory Spinosaurus aegyptiacus. The study was the first evidence that some dinosaurs could swim. And now the discovery of more than a thousand dinosaur teeth reinforces that theory even more.
The Spinosaurus aegyptiacus was a fifty-foot beast that could weigh a whopping six tons. The world’s only extant skeleton of a Spinosaurus aegyptiacus has been found in the so-called “Kem Kem Group,” a region in the Moroccan Sahara. Although this desert today represents a dry and arid environment, it was home to a vast river system in days gone by. Researchers concluded in 2008 that the Spinosaurus aegyptiacus must have been a fish-eating dinosaur, displaying traits of an amphibious lifestyle. This is evident, for example, from its relatively short hind legs, wide feet and elongated jaws with conical teeth. Still, this theory met with much criticism, mainly because the skeleton did not show any pronounced bone structures that must have been necessary for the dinosaur to move through water.
In 2019, researchers decided to return to the Moroccan plain. And here they were delighted to find more fossil remains of a Spinosaurus aegyptiacus. The most surprising find was a complete fin-like tail. After a thorough analysis, this tail appeared to belong to a real swimming “river monster” that was in the water and could use its tail to move through the water. It means that Spinosaurus aegyptiacus could move its tail back and forth to propel itself through the water that way. And that turned many views on dinosaurs upside down. Because it means that swimming dinosaurs may actually have existed.
Still, these findings cried out for further research. And that has now happened. In a new study, researchers once again returned to the old Moroccan riverbed in search of even more remains of the Spinosaurus aegyptiacus. And surprisingly, they found an abundance of teeth here, most of which must have once been in the mouth of Spinosaurus aegyptiacus. “Spinosaurus’ teeth have a clear surface,” explains researcher Aaron Quigley. “They have a smooth round section that shimmers when held up to the light.” In total, no fewer than 1,200 teeth were found, almost half of which could be attributed to Spinosaurus aegyptiacus. “This huge number reveals that Spinosaurus was abundant in the area,” concludes researcher David Martill. “We know of no other place where so many dinosaur teeth have been found.”
The discovery now conclusively establishes, according to the researchers, that the Spinosaurus must have been a terrifying river monster. “The large number of teeth found compared to those of other dinosaurs is a reflection of their aquatic lifestyle,” explains Martill. “An animal that spends much of its time in the water contributes to deposits in rivers much more often than the dinosaurs that only occasionally visited the river, for example to drink water along the banks.” The fact that so many teeth were found means that the beast spent its entire life in the water. “We can now confirm that these gigantic dinosaurs not only lived in these places, but also died there,” continues Martill. “The results of this study are fully consistent with the idea of a real aquatic river monster.”
In the vast Moroccan Sahara desert, more special remains have been discovered. “The Kem Kem Group’s riverbeds not only harbor remains of Spinosaurus, they have also found remains of many other creatures, including sawfish, coelacanths, crocodiles, flying reptiles and other land-dwelling dinosaurs,” sums up researcher Thomas Beevor. Researchers therefore think that 100 million years ago ferocious predators infested the area. It is therefore not without reason that scientists designate this place as the most dangerous place in the history of the earth.