FOSSILS ET AL.
Cool dinos — the Spinosaurus
The history behind its discovery and description
Ah! I have been dying to write about this. For most of us dinosaur fans, maybe the star of the show will always be the Tyrannosaurus rex, the icon of the Jurassic Park franchise and the most ferocious meat eater to ever live. But in some other part of the world, some 11,000 kilometers away from where the first T. rex fossils were found, scientists discovered something astounding: the remains of an animal that was going to change how dinosaurs were viewed.
In the twilight months of 1912, a search conducted in Egypt revealed what looked like long vertebrae. After a detailed inspection by German paleontologist Ernst Stromer, it was clear that these belonged to a totally new species. Further parts of its skull, jaws, and teeth helped scientists to reconstruct its shape in theory. This new species was eventually named Spinosaurus aegyptiacus (the spined lizard of Egypt), owing to the distinctive elongated spines found on its vertebrae, which gave it a unique appearance among theropod (meaning “beast-footed” and walking on two legs) dinosaurs. With a total length of over 45 feet, this was the largest carnivore ever to exist. Sadly, amidst the ongoing research, an Allied bombing of Germany during the Second World War destroyed the first described specimens (what we call the holotype) of this beautiful animal.
Due to the lack of fossils to study, the research on this dinosaur's biology, ecology, and evolution slowed down, and scientists began to give their theories based on the available knowledge. It was believed to have lived in the late Cretaceous period, some 98 million years ago. It was a semi-aquatic creature that lived near water bodies and hunted fish for food, as evidenced by the calcium deposits in its teeth. It had sharp claws that it used to skim the fish caught and a crocodile-like tail to help it swim. In early reconstructions of its body, it was thought to have looked like a proper theropod, but it was also thought to be capable of walking on all fours.
But life is known for giving everyone a second chance, and so it did to the fossil hunters when Nizar Ibrahim, a German-Moroccan paleontologist, visited the Moroccan Sahara and began searching for Spinosaurus fossils in a region famous for fossil excavation by local fossil hunters back in 2008. Nizar, who felt a close connection to Stromer because of his German roots, was determined to rediscover this dinosaur. Over the next four years, Nizar and his colleagues recovered many more parts of a skeleton. Once all these parts were prepared, computer simulations were performed to fill in the missing parts. A detailed reconstruction of the jaw and tail was made.
Through these reconstructions, some new remarkable facts were revealed. It was discovered that the Spinosaurus had smaller hind limbs than previously thought of, so it could not stand up like other theropods did. Some theories even suggested that it spent most of its time underwater, like crocodiles, but this is still debatable.
The huge sails on its back are supposed to serve display purposes to attract females. However, there is still so little known about this animal that nothing can be said for sure. One thing is certain: it was the apex predator in its region.
Why this absolute beast went extinct is a highly debated subject. Spinosaurus did not live at the end of the Cretaceous period, so the asteroid did not wipe it out. Scientists have proposed two possible reasons: climate change and competition.
The climate change theory — 90 million years ago, the Earth experienced a global warming event. Because of Earth's temperature change, the swamps Spinosaurus called home started converting into deserts. With the evaporation of water, the fish, which were its main food, disappeared. Because of this, Spinosaurus was slowly forced to go hunting on land, where it would face other theropods living in the region. Bite marks on the spines of a recovered fossil indicate that the specimen fought with another dinosaur, which may often have been fatal for it.
The competition theory—This theory takes into account the presence of large crocodylomorphs alongside Spinosaurus during its time on Earth. These crocodylomorphs were after the same food sources as the dinosaur, and being on the same turf, the competition led to Spinosaurus' eventual downfall.
We may never know what ended these dinosaurs, but it may be that the Spinosaurus was undoubtedly a gigantic predator, the likes of which the Earth has never seen since its extinction. It was the first known aquatic or semi-aquatic dinosaur. Its life on Earth also highlighted the devastating effects of various climatic changes that this planet went through in the past on life on Earth. It highlighted how the now dry and hot Sahara desert was once a wet swamp full of life. It also points out the fact that life is highly dependent on climate.
Perhaps there is no better quote to end this article than this one:
If we measured success by longevity, then dinosaurs must rank as the number one success story in the history of land life.
— Robert Baker
Published in Fossils et al. Follow to learn more about Paleontology and Evolution.
