Scientists have found more than a thousand fossilised teeth in a prehistoric river bed and this gives an exemption to palaeontologists beliefs that dinosaurs are land-based.
The Spinosaurus aegyptiacus species had huge fin-like tail, and some scientists believed that this dinosaurs had aquatic life.
And this recently found hundreds of teeth, about half of the huge haul discovered in Morocco, seems to be a huge evidence.
Spinosaurus teeth. (Beevor et al., Cretaceous Research, 2020)
“From this research we are able to confirm this location as the place where this gigantic dinosaur not only lived but also died,” says palaeobiologist David Martill from the University of Portsmouth.
“The results are fully consistent with the idea of a truly water-dwelling ‘river monster.'”
The huge haul of teeth were recognized as that of dinosaurs and some aquatic animals. Measuring to about 1,200 fossils, the researchers discovered that about half were from the Spinosaurus.
“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,” they write.
In 2014, palaeontologist Nizar Ibrahim initially brought about the case for a semi-aquatic Spinosaurus. Other scientists who assessed the fossils thought differently, asserting that the dinosaur lived as a topsy-turvy floater at best, navigating into the water due to hunger for fish. Its skeleton, they said, was unsinkable.
However, earlier this year, Ibrahim and his colleagues discovered a fossilised Spinosaurus tail – which would change the narrative
The discovery strengthened the idea that this giant animal used up some time swimming in the water. The researchers named it the “unambiguous evidence for an aquatic propulsive structure in a dinosaur”.
Ibrahim and his colleagues are presently arguing that the spinosaur was not just semi-aquatic but “largely aquatic” and spent “much of its life in water”, where its teeth were remove at what is assumed to be a similar rate to modern crocodiles.
The historical waterway, now long gone, used to be home to Cretaceous creatures like the sawfish, crocodiles, flying reptiles and, along its banks, dinosaurs.
While at reconnaissance field work in the south east of Morocco, scientists found a sandstone bed of bone completely ridden with Cretaceous fossils.
Just over a kilometre away, the team came across several miners in action, and they acquired all the fossils the workers had discovered in the historical river bank.
Spinosaur teeth are easy to identify thanks to the specific features, the team discovered hundreds of fragments from the Spinosaurus.
The authors acknowledged that the teeth might have been compiled here from the Spinosaurus swimming along the banks of the river, seizing its prey from the safety of the shore.
In fact, the authors announced that the brief hindlimbs of spinosaurs are only compatible with one aspect of avian locomotion: active swimming.
“With such an abundance of Spinosaurus teeth, it is highly likely that this animal was living mostly within the river rather than along its banks,” argues University of Portsmouth palaeontologist Thomas Beevor.