Spinosaurus became famous after defeating Tyrannosaurus Rex in Jurassic Park III, but since its discovery in 1912, it has always been a top contender for being the longest theropod of all time. Spinosaurus’ tall skin sail of bony blades was just one of its incredible features during its life in the Early Cretaceous. It’s nearly a century since its first fossil remains were found and now science has discovered a lot more about this dinosaur and its accurate size. Here are 5 most amazing facts about Spinosaurus.

Spinosaurus Sketch

  • Where it Lived – Present-day Africa
  • Habitat – Flood Plains
  • Size – 46-59 feet long
  • When it Lived – Middle Cretaceous Period, about 95 million years ago.


It’s a subject under much debate. Spinosaurus was described by German paleontologist Ernst Stromer in 1915 to be around 46 feet long and weighing 7.4 tons. Future specimens were incomplete as well but were reported to be around the same range of size. However, the most recent Spinosaurus fossil discovery in 2005 had an enormous skull that measured six feet long. The dinosaur is known for its long narrow snout and six feet was over a foot longer than the largest Tyrannosaurus Rex skull in the world (which was 4’11 long). The specimen found was estimated to be 52-59 feet long, making it the longest theropod dinosaur that ever lived – even longer than T-Rex.

But due to the incomplete remains found so far and the fact that the skeletal framework of Spinosaurus was much different compared to its robust and heavier built “contenders” like Tyrannosaurus Rex, Giganotosaurus, and others, experts still disagree on which is the biggest. It was longer but it was lighter, which is why it’s not considered to be the largest dinosaur predator. Its huge sail made it seem larger than it actually was.

Spinsosaurus vs Tyrannosaurus Rex – Who Would Win?

In the movie Jurassic Park III, Spinosaurus snapped Tyrannosaurus Rex’s neck without much of a fight. This battle was fictional, of course, since the two species lived vast distances and millions of years apart from one another. But in a realistic scenario, which dinosaur would win in a battle?

Spinosaurus was lighter than Tyrannosaurus Rex but it had a longer skull and snout. Its teeth were very similar to a modern day crocodile’s, and it had extra teeth in the lower jaw – specially designed for holding struggling prey in a crushing grip. Spinosaurus had longer forelimbs, a large sickle-shaped thumb claw, and powerful shoulders. A lighter build also meant more agility.

Tyrannosaurus Rex on the other hand was heavily built, had one of the most powerful bite forces, and is arguably the “king.” But to this day, scientists still debate whether it was actually a scavenger. A large consenus states that it could have been both. Unfortunately, the world will never know which species would win.

Spinosaurus Size


Spinosaurus was an apex predator like T-Rex but its skeletal structure (especially the skull) resembled other spinosaurs like Baryonyx and Suchomimus. Its long narrow snout, sharp teeth (without serrations), and ability to walk on all fours indicate that it was designed to hunt large fish and perhaps even large dinosaurs.

Its large hook-like thumb claw was also built to grab fish like a grizzly bear. Its diet consisted of both fish and meat, depending on which was available. There was no doubt it lived near water.


Spinosaurus’ brightly colored sail is what makes it stand out. Without it, it wouldn’t look as menacingly large. But this bony sail has other functions. Spinosaurus could have used it to attract mates as a display, support a tall fleshy lump to store food, and to control its body temperature. This indicated that it was most probably cold-blooded – unable to regulate its own temperature.


Spinosaurus was an “advanced theropod”, making it one of the more intelligent dinosaurs. Its EQ (Encephalization Quotient), which measures brain size relative to body weight, proved that. As an apex predator, it had no direct threats and it was large enough to take down sauropods.

Based on its structure, experts believe Spinosaurus was very similar to a crocodile and a grizzly bear, in terms of possible hunting habits. Since its original remains were destroyed in an allied bombing during World War II, it’s difficult to gain a stronger understanding of the dinosaur. There may even be a larger species we just haven’t discovered yet.


David Lambert, Darren Naish, and Elizabeth Wyse. “Double Beams.” Encyclopedia of Dinosaurs and Prehistoric Life. DK Publishing, 2008.

“Spinosaurus”. Enchanted Learning.

dal Sasso, C.; Maganuco, S.; Buffetaut, E.; and Mendez, M.A. (2005). “New information on the skull of the enigmatic theropod Spinosaurus, with remarks on its sizes and affinities“. Journal of Vertebrate Paleontology25 (4): 888-896. doi:10.1671/0272-4634(2005)025[0888:NIOTSO]2.0.CO;2

“Museum unveils world’s largest T-rex skull”. Montana State University.