There has been mounting evidence that one of the Cretaceous’s largest predators was river-dwelling rather than a terrestrial hunter. A new study published in the journal Cretaceous Research may now have definitely proven that Spinosaurus was indeed an aquatic dinosaur after the discovery of an enormous glut of dino dental records.
A team of researchers from the University of Portsmouth, United Kingdom, poured over a collection of more than a thousand teeth to conclude that this giant predator was, beyond a reasonable doubt, an enormous river monster. Research earlier this year had already brought weight to the theory that they might be water-dwelling dinosaurs as it was discovered that their tails were perfectly adapted for aquatic locomotion. A swimming giant, Spinosaurus aegyptiacus could grow to lengths of 15 meters (49 feet) snout-to-tail, weighing in at around 6 tons.
This latest research looked at 1,261 teeth and tooth fragments retrieved from an ancient river bed called the Kem Kem in Morocco, which in its heyday surged through the Sahara Desert around 100 million years ago. As they were sifting through their finds it became clear that Spinosaurus, whose teeth are easy to spot thanks to their distinct surface that has round cross-sections that glint in the light, had contributed the majority of those collected.
"The huge number of teeth we collected in the prehistoric river bed reveals that Spinosaurus was there in huge numbers, accounting for 45 percent of the total dental remains,” said David Martill, a professor of Palaeobiology at the University of Portsmouth, in a statement. “We know of no other location where such a mass of dinosaur teeth have been found in bone-bearing rock.
"The enhanced abundance of Spinosaurus teeth, relative to other dinosaurs, is a reflection of their aquatic lifestyle. An animal living much of its life in water is much more likely to contribute teeth to the river deposit than those dinosaurs that perhaps only visited the river for drinking and feeding along its banks.”
The Kem Kem river beds are a popular haunt for Spinosaurus remains in general, which are often found among a diverse cast of Cretaceous creatures including sawfish, coelacanths, crocodiles, flying reptiles, and terrestrial dinosaurs. The researchers state that though some land-living dinosaur remains are found within the Kem Kem, the sheer volume of Spinosaurus teeth proves beyond a reasonable doubt that they lived and died in the river instead of along the banks.
"From this research we are able to confirm this location as the place where this gigantic dinosaur not only lived but also died. The results are fully consistent with the idea of a truly water-dwelling, 'river monster.'"