Spinosaurus is the biggest predatory dinosaur known, standing nearly two meters taller than the tallest Tyrannosaurus rex, yet how it hunted has been a source of contention for decades.
Paleontologists have adopted a novel method for deciphering the lifestyles of long-extinct species in a new paper.
A group of paleontologists used a novel approach to deciphering the lifestyle of long-extinct species in new research published today in Nature, and they did this by examining the thickness of their bones.
Some experts believed the animal can swim, but others said it waded like a heron.
According to new research, the carnivorous dinosaur's thick bones allowed it to hunt underwater.
Spinosaurus has high-density bones according to discovery
PATRICK T. FALLON/AFP via Getty Images
Dr. Nizar Ibrahim, a paleontologist at the University of Portsmouth and a National Geographic Explorer, discovered several fragments of a Spinosaurus skeleton in North Africa's Sahara Desert during the previous decade, as per ScienceDaily.
The skeleton revealed by Dr. Ibrahim and his colleagues included retracted nostrils, small hind legs, paddle-like feet, and a fin-like tail, all of which strongly suggested an aquatic existence.
"We braved sandstorms, floods, snakes, scorpions, and more to dig the world's most perplexing dinosaur, and now we have several lines of evidence all pointing in the same direction the skeleton truly has 'water-loving dinosaur' written all over it!" said Dr. Ibrahim.
The team discovered that Spinosaurus and its close family member Baryonyx from the Cretaceous of the UK both had high-density bones that would have allowed them to fully immerse themselves beneath the water to hunt by analyzing the density of spinosaurid bones and trying to compare them to other animals such as penguins, hippos, and alligators.
Spinosaurids were known to have aquatic affinities; their extended jaws and cone-shaped teeth are comparable to those of fish-eating carnivores, as well as the ribcage of Baryonyx from Surrey even included half-digested fish scales.
According to Dailymail, paleontologists believe that this species waded instead, or spent more time on land, like other dinosaurs.
"The fossil record is challenging among spinosaurids, there are just a few incomplete skeletons, and we don't have any full skeletons for these dinosaurs," said Matteo Fabbri, the study's principal author and postdoctoral scientist at the Field Museum.
Previous researchers have focused on the translation of physiology, and when there are such contradictory views around the same remains, it's a strong sign that some of those may not be the best proxies for us to deduce the ecosystem of extinct animals, says the scientist.
While most mammals live on land, whales and seals live in the sea, and some mammals such as otters, tapirs, and hippos are semi-aquatic.
Penguins and cormorants are examples of birds, whereas alligators, crocodiles, marine iguanas, and sea snakes are examples of reptiles.
Non-avian dinosaurs that did not evolve into birds were the only group that did not have any water-dwellers for a long period.
The researchers compiled a massive collection of femoral and ribcage bone cross-sections from 250 prehistoric and current creatures, comprising both land and water inhabitants and animals from a few grams to several tonnes.
The investigators matched these creatures' bone cross-sections to those of Spinosaurus and its cousins Baryonyx and Suchomimus.
When the scientists used this concept to spinosaurid dinosaur bones, they discovered that Spinosaurus and Baryonyx both had the sort of thick bone consistent with complete submergence.
The bones don't lie, and now we know that even the internal structure of the bones is completely consistent with our analysis of this animal as giant predators scavenging fish in vast river systems, using its paddle-like tail for propellant.
