Tyrannosaurus Rex vs. Spinosaurus – Killers of Giants
Scientists’ knowledge of dinosaurs has improved a lot over the last decade or so. New fossil finds coupled with new research techniques have allowed paleontologists to learn a great deal about these reptiles. When we visit schools or work in museums, our staff are bombarded with questions and one of the most popular is: what is the largest carnivorous dinosaur of all? To be honest, this is a tough question to answer, but among the contenders would be Spinosaurus (Spinosaurus aegyptiacus), a rare sail-backed dinosaur that may have reached a length of more than 18 meters.
Spinosaurus appeared in the first episode of the BBC television series “Planet Dinosaur”. This episode was titled “Lost World” and focused on the dinosaur discoveries of North Africa. This part of the world around ninety-five million years ago was home to a variety of huge prehistoric animals, giant crocodiles, huge sauropods and at least two large carnivores. The carnivores in question are Carcharodontosaurus and perhaps the largest carnivore of them all: Spinosaurus.
A tale of tape
Like two heavyweight boxing contenders, let’s take a quick look at what we know about Spinosaurus compared to T. rex.
T. rex – length = 13-14 meters, weight 5.5-7 tons, skull size 1.75 meters
Spinosaurus – length 12-18 meters, weight 4 to 20 Tons, skull size 2 meters
Based on these statistics, it appears that Spinosaurus is the largest animal, but we have to take into account the actual fossil evidence, when we do so a more confusing picture emerges.
Something like thirty fossil specimens of T. rex are known, with at least half a dozen individual skeletons containing at least 40% complete fossil material, including skull material. However, for Spinosaurus the fossil record is much less complete. Only six specimens have been found to date. Most of what paleontologists know about Spinosaurus comes from this scant material and from the expansion of fossil bones from related genera such as Suchomimus, Baronyx, and Irritator.
The most complete Spinosaurus fossils found to date were discovered by a German expedition to the Western Egyptian desert. This expedition was headed by Ernst Stromer von Reichenbach, who should perhaps be as famous today as Cope and Marsh. However, Stromer was dogged by misfortune and the story of Spinosaurus is one of missed opportunities and mistakes.
The discovery of the spinosaurus
In November 1911, Stromer’s party set sail for Egypt, on a quest not to find dinosaurs but to find evidence of early hominids. Stromer believed (quite rightly, as it turned out), that humanity originated in Africa. At the beginning of the 20th century there were two contrasting theories about the origins of our own species. Some scientists believed that H. sapiens evolved in Europe, while other scientists, including Stromer, believed that humanity originated in Africa. Stromer’s group explored a number of areas before visiting the Bahariya Oasis in western Egypt, which they thought would be Eocene deposits, a potential location for primate fossils. The team discovered the remains of several new types of dinosaurs, including two large predators: Carcharodontosaurus and perhaps most famous of all, Spinosaurus.
The remains were fragmentary, part of the lower jaw, some vertebrae, and of course those huge neural spines, the largest of which was nearly six feet tall. It is these spines that give this dinosaur its name, it is believed that the spines supported a huge sail-shaped structure on the animal’s back. It is unclear what this device was used for (thermoregulation, fat storage, visual signaling). However, Stromer was aware that he had to deal with some huge fossilized bones.
He was struck by the size and scale of the specimens the expedition collected, he was quoted as saying “…I don’t know how to conserve such gigantic species.” The team ended up mixing flour and water to make a paste and tearing up strips of cloth which they then soaked in this mixture and applied to the fossils to make a kind of protective jacket for their finds.
Getting the fossils to Germany proved very difficult. Egypt was under British control and on the eve of World War I diplomatic relations between Britain and Germany were strained. One box was able to leave the country, but the rest remained in Egypt until the war ended. They were not finally returned to Stromer until 1922.
Spinosaurus (Spinosaurus aegyptiacuslisten)) was formally named and scientifically described by Stromer in 1915. Stromer thought that this Egyptian dinosaur was at least as large as Tyrannosaurus rex, which had been named only nine years earlier.
Unfortunately, the boxes that were returned to Germany in 1922 contained fossils that had been damaged. Many of the specimens were in poor condition, and Stromer spent the next decade repairing and studying them. More descriptions, drawings, and even some photographs of the Spinosaurus fossils were made, but in the 1930s Stromer fell out of favor with the Nazi Party and had increasing difficulty getting his work published.
April 24/25, 1944 – Destruction of fossils
Stromer had pleaded with authorities to remove his Spinosaurus fossil material and other specimens from the Munich museum, where they were stored for much of World War II. As Allied bombing raids became more frequent, Stromer urged the authorities to allow him to transport the samples to a secure storage area, such as a coal mine or other underground facility. His pleas went unheeded and his fate finally ran out on the evening of April 24, the morning of April 25, 1944 when a British night bombardment effectively leveled the museum and the surrounding area. Stromer’s life’s work was all but destroyed, including the Spinosaurus fossils. The holotype specimen of him is no longer available and is therefore not available for study of him. Only a few tantalizing photographs remain of Stromer’s Spinosaurus fossils.
Morocco – New discoveries
Several other fragmentary Spinosaurus fossils have been found since Stromer’s time. Not in Egypt but in Morocco, this has led scientists to describe a potential second species of Spinosaurus. Canadian paleontologist Dale Russell has studied the Moroccan fossil material, some of which was provided by an Italian museum that had originally received this specimen from a private collection. Although, still very fragmentarily, scientists have named and described a second species of Spinosaurus – maroccansus spinosaurusalthough this second species is not fully accepted by the scientific community as a separate species.
In terms of confirming the size of Spinosaurus, based on the remaining fossil evidence and the holotype from Egypt’s Bahariya Oasis, we can safely say that this theropod was very large, whether or not it was the largest land carnivore that ever lived. it’s harder to say. More research and more complete fossil specimens are needed.