The original Spinosaurus fossils were discovered in 1915 and obliterated by Allied bombs hitting Munich in 1944, turning the largest carnivorous dinosaur into a ghost for decades. When new fossils emerged from Morocco in 2014, they revealed a creature so bizarre that paleontologists have been in open warfare ever since about whether it was a 15-meter wading heron from hell or an otter-croc hybrid that chased fish underwater using a paddle-shaped tail unlike any other theropod.
3blindMies, CC BY-SA 4.0, via Wikimedia Commons
A Dinosaur Annihilated and Reborn
The first evidence of Spinosaurus aegyptiacus was discovered in Egypt by German paleontologist Ernst Stromer in 1912 and described in 1915. The fossils revealed a theropod dinosaur with enormous, 1.65-meter-long spines on its back. For decades, these bones were the only known material. As a known critic of the Nazi party, Stromer's pleas to move the unique fossils from their Munich museum to a safer location during World War II were ignored. In April 1944, an Allied bombing raid destroyed the museum and the entire original skeleton, leaving only Stromer's notes and photographs behind. Spinosaurus became a paleontological phantom.
The dinosaur was resurrected nearly a century after its discovery. New fossils, unearthed beginning in 2014 from the Kem Kem Group of Morocco, have redefined the animal. This geological formation, dating to about 95-100 million years ago, was not a desert during the Cretaceous. It was a vast, swampy river system, sometimes called the "River of Giants." Predators dominated the ecosystem and predators and teeming with huge aquatic prey, including the 8-meter-long sawfish Onchopristis and giant coelacanths. The new fossils, including a partial skeleton designated FSAC-KK 11888, revealed an animal stranger than anyone had imagined and ignited a fierce scientific feud.
An Aquatic Predator or a Prehistoric Wader?
The 2014 fossils showed Spinosaurus had a combination of bizarre features: dense leg bones for buoyancy control, short muscular hind limbs, flat-clawed feet, and nostrils positioned high on its long, crocodile-like snout. These traits suggested a semi-aquatic lifestyle, a radical concept for a predatory dinosaur. The debate intensified in 2020 with the discovery of a nearly complete tail from the same specimen. It was not a stiff tapering tail common to other theropods. Instead, it was a deep, flexible, paddle-like structure formed by long, thin spines, resembling a giant fin.
Proponents of the aquatic hypothesis argue this tail was a powerful engine for underwater propulsion. Experiments using a robotic model of the tail showed it could produce eight times more thrust in water than the tails of terrestrial theropods. This evidence shows an active pursuit predator that hunted large fish in deep river channels.
Other paleontologists strongly contest this interpretation. They argue that the dinosaur's sail and overall body shape would create immense drag, making it a clumsy and inefficient swimmer compared to a crocodile. This opposing camp suggests Spinosaurus was a wading, shore-bound predator, using its anatomy to hunt in the shallows like a modern heron, while the impressive sail and tail were primarily for display. The argument continues, with each new analysis adding to the debate over the true nature of this strange dinosaur.
💡Fun Facts
Ernst Stromer urged the Nazi-supporting museum director to move the original *Spinosaurus* fossils to safety, but his requests were denied. Two of Stromer's sons were killed in the war, and a third was taken as a prisoner of war.
The Kem Kem Group is unusually full of predator fossils, including at least four large theropods like *Carcharodontosaurus* and several giant crocodyliforms.
*Spinosaurus* shed its conical teeth frequently, so they are a very common find for fossil hunters in the Kem Kem region.
To test the function of its unique tail, scientists created a plastic, robotic version and measured its propulsive power in a water flume.
The Kem Kem Group is a vast, unfenced geological region and is always accessible, though it is extremely remote.
Admission
Access is free, but requires a guided tour with a 4x4 vehicle for navigation and safety.
Accessibility
This is a rugged, remote desert environment with no paved roads, facilities, or public transportation. It is not suitable for individuals with mobility challenges.
The Kem Kem Spinosaurus DebateDrâa-Tafilalet, Morocco
