It ate whole sharks, and came equipped with feet like paddles and sealable nostrils that allowed it to swim under water.
Spinosaurus, the largest known predatory dinosaur, now turns out to be the only known dinosaur that spent most of its time swimming. While palaeontologists envisaged it as a sort of gigantic heron, it was actually an enormous version of a crocodile.
The 20-metric-ton beast boasted a crest on its back, akin to a boat’s sail, held aloft with spines as tall as an average human. Its long tail, narrow hips and paddle-shaped feet probably helped the 15-metre creature move through the water with ease, experts said.
Spinosaurus also had dense bones to help control its buoyancy in water, and a long snout with high-set nostrils that could allow easy breathing while partially submerged.
“Taken together, these features strongly suggest that Spinosaurus was the first dinosaur that spent a significant amount of time in the water,” said lead author Nizar Ibrahim, a paleontologist at the University of Chicago. The scientists based their findings on new fossils from the Moroccan Sahara as well as specimens in museum collections.
The discovery is a boon to paleontologists, who have had little to study when it came to Spinosaurus even though it was first identified from bones found in Egypt in 1912 by German paleontologist Ernst Freiherr Stromer von Reichenbach.