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Spinosaurus aegyptiacus Dinosaur Facts

95 million years ago, the southeastern region of Morocco in North Africa was home to the world's largest fauna of giant predators: coelacanths the size of a car, huge crocodiles like Sarcosuchus, sharks, flying reptiles and a variety of carnivorous dinosaurs. The red rocks of the Cretaceous era of these arid communities have unearthed the remains of great theropods such as the Carcharodontosaurus (which can be seen in the exquisite painting "Thunder across the Delta" from paleoartist Mark Hallett), the Spinosaurus and many other lesser known species. The tropical Oasis of the Kem Kem geological formation was an earthly paradise and the ideal place for a flourishing biodiversity of formidable, massive creatures. Often described as the most dangerous place in the history of the planet, this region of the world had more predators than herbivores in its ecosystems.

Even bigger than the Tyrannosaurus

From this environment was born the Spinosaurus, a piscivorous theropod dinosaur whose dimensions surpassed that of the Tyrannosaurus Rex. As portrayed during his cameo in the movie Jurassic Park III, this 50-foot-long dinosaur was so voracious that it could make a mouthful of a T-Rex. Spinosaurus moved on its hind legs, its crocodile jaw was filled with sharp teeth and his back had the distinctive mark attributed to this dinosaur: a huge sail mounted by dorsal spines nearly 6 feet high.

Scene from Jurassic Park III - Spinosaurus vs Tyrannosaurus

Unknown real appearance

The Spinosaurus is one of the great puzzles of paleontology since it is known only by a few rare bones and therefore its real appearance remains until today speculation.

Initial discovery

The story of Spinosaurus begins in 1912 when the German paleontologist Ernst Freiherr Stromer von Reichenbach unearths in the oasis of El Bahariya in Egypt strange bones belonging to an unknown dinosaur: some vertebrae and pieces of skull, especially the lower part of the jaw whose unusual teeth were probably used to catch fish. The fossil also had long backbones reminiscent of the crested chameleon.

A few years later, in 1915, Stromer carefully documented his finds through illustrations and photographs. The remains were subsequently sent to the Munich Museum for permanent exhibition. Unfortunately, twentieth-century Germany is characterized by periods of war and the specimen of Spinosaurus aegypticus was completely destroyed in bombings of the Second World War. All that is left today are various detailed descriptions which are enough to get a good idea of the fossil found by the German researcher.

New reconstruction

Reconstruction of Spinosaurus

Very recently, there has been renewed interest in Spinosaurus after new bones have been discovered in Kem Kem rocks in Morocco. In 2008, a palaeontologist from the University of Chicago on an expedition to the Sahara Desert in search of fossils to complete a doctoral thesis was presented with a gift from a man with a mustache; a cardboard box filled with remains of dinosaurs. The man wanted to get the expertise of the imminent American researcher to identify the bones. When he opened the box, he discovered a long, pointed bone that turned out to be a Spinosaurus dorsal spine.

In 2013, this same scientist heard from one of his colleagues that the Museum of Natural History in Milan had possibly acquired a specimen of Spinosaurus. While visiting the museum, Dr. Ibrahim found himself facing a partial skeleton of Spinosaurus lying in the basement of the museum. The fossils came from a private collector but museum staff suspected he had found them in Morocco. Comparing the two groups of remains, the Chicago doctor noticed strange similarities in bone tones, which led him to believe that they probably came from the same geographical location.

That was enough to convince him to return to the African desert in search of the mysterious man. By a stroke of luck, he managed to locate and convince the local fossil hunter to drive him to the exact spot where he had made his discoveries: a cave-like hole near a cliff in the rocks formation of Kem Kem in the Sahara. While digging deeper, he found other Spinosaurus spines and bones, including the hips and hind legs.

After sifting through Stromer's original documents to confirm that the newly discovered fossils corresponded to the same dinosaur species as in 1912, a team set out to carry a modern reconstruction of Spinosaurus. They took computerized tomographies of the new fossils as well as some bones exposed in different museums and created digital models from the Stromer archives. They then printed a 3D composite skeleton and added skin to it. It is a kind of super mixture from different sources, a chimera. Although the appearance of the true Spinosaurus probably diverged from the composite, it remains the best scientific representation available to date of this animal.


Fossil of Spinosaurus
National Geographic Museum

The Spinosaurus is very interesting not only because it was even larger than the Tyrannosaurus but also because several anatomical details indicate that it was the only dinosaur of the Mesozoic era able to swim.

The first evidence that he was an underwater animal is that his femur was shorter proportionally than other theropods and that the bones of his feet were flat, with wide toe claws. Spinosaurus had a hard time chasing down prey on dry land.

Also, the bones of this dinosaur are solid; there is no empty space inside. Theropods of the same lineage as Tyrannosaurus and Allosaurus had long, light bones with cavities inside which allowed them to move easily. The bones of Spinosaurus are more like those of the first whales and other semi-aquatic mammals. Comparing with other animals that made the transition from land to water, this is the best evidence that Spinosaurus preferred to swim.

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