Temporal range: Early–Late Cretaceous
|An artist's illustration of Spinosaurus aegyptiacus|
Stromer et al., 1915
| †Spinosaurus aegyptiacus|
</div>Spinosaurus (spin·o·saur·us/pronounced SPINE-oh-SORE-us) ("spine lizard") was a large theropod dinosaur that inhabited the Kem Kem River Basin of Early Cretaceous Egypt (112 mya - 93.5 mya). It is the 4th largest theropod, only being exceeded in size by Tyrannosaurus Rex , Mapusaurus and Deinocheirus.
Currently; The Spinosaurus is only known from several poor, incomplete and extremely fragmentary specimens. The holotype specimen was discovered in 1912 in Egypt, by German paleontologist Ernst Stromer. The specimen included the lower jaw, teeth, several neural spines, ribs, vertebrae and a single phalanx.
Stromer measured the maximum length of Spinosaurus as 12 meters (39 ft), despite the holotype measuring only about 10 meters (33 ft) long. Sadly, the holotype specimen was destroyed after the museum, where the fossils were displayed at, was destroyed by allied forces during the night of 24/25 April 1944.
Newer discoveries from Tunisia in 1999 and Morocco in 2005 and 2014 suggest that Spinosaurus may have reached 15.6 meters (49 ft) in length. A size estimate by Dr. Dal Sasso suggests that the animal could have capable of reaching a length of 18 meters (59 ft); albeit it is not certain; latest research confirmed this as the estimations gave it a size greater than 15m.
The largest known specimen was found by Spanish paleontologist Cristiano Dal Sasso, in Morocco in 2005. The specimen includes a near complete upper jaw which measures about 1.75 meters (5.7 ft) long, with a few well-preserved teeth. The latest finds, also discovered in Morocco, were discovered by Dr. Nizar Ibrahim and Dr. Paul Sereno. The specimen includes fragmentary remains, determined to be hind limbs, four neural spines, gastralia and some parts of the skull from the postorbital area.
Ibrahim and Sereno made a new reconstruction of this animal, suggesting that Spinosaurus may have had a quadrupedal posture. However, this reconstruction has been criticized by both the public and the scientific community, although some people and scientist support it, some people (including scientists) believed it to be a chimera or error by Ibrahim due to an error in the original paper's description of how the measurements were done. Including Scott Hartman & John Hutchinson. A new revision has been published which has proved supporting Ibrahim's measurements. Evers et al. 2015 argued that Sigilmassosaurus was a distinct genus, and therefore doubted whether the material assigned to Spinosaurus by Ibrahim et. al. even belonged to it.
It is unclear whether one or two species are represented in the described fossils. The best-known species is Spinosaurus aegyptiacus from Egypt, although a potential second species named Spinosaurus maroccanus (which is currently considered to be a junior\nomen dubium) has been discovered in Morocco in recent times it is not officially recognized by this name. Spinosaurus Maroccanus may be sigilmassasaurus.
According to 2014 reconstruction's body shape and limb orientation, it's biomechanics are thought to be comparable to avians like Pelicans and reptiles like crocodiles. Spinosaurus is once thought to have been semi-aquatic due to its diminutive limbs, flattened toe claws, webbed feet (inferred from relatives like Baryonyx ), long tail and torso and evidence of predation upon large fish such as Onchopristis. Spinosaurus' locomotion method on land is unclear. Plausible theories include a Bipedal Gait with an S-Curved neck similar to a Swan or a Pelican; or a more erect bipedal gait similar to most theropods. A quadrupedal stance has been suggested by Ibrahim et. al., however it is now deemed impossible for the animal.
This diagram shows possible method of land-based locomotion for a short-legged model of Spinosaurus :
Two species of Spinosaurus have been named: Spinosaurus aegyptiacus (meaning "Egyptian spine lizard") and Spinosaurus maroccanus (meaning "Moroccan spine lizard")
The first described remains of Spinosaurus were found and described in the early 20th century. In 1912, Richard
Markgraf discovered a partial skeleton of a dinosaur in the Bahariya Formation of western Egypt. In 1915, German paleontologist Ernst Stromer published an article assigning the specimen to a new genus and species Spinosaurus aegyptiacus.Fragmentary additional remains from Bahariya, including vertebrae and hindlimb bones, were designated by Stromer as "Spinosaurus B" in 1934.Stromer originally believed they belonged to juvenile Spinosaurus, but after closer research and bone analysis, he determined that specimen was actually a chimera, with remains of Sigilmassasaurus and Carcharodontosaurus.
S. maroccanus was originally described by Dale Russell in 1996 as a new species based on the length of its neck vertebrae. Specifically, Russell claimed that the ratio of the length of the centrum (body of vertebra) to the height of the posterior articular facet was 1.1 in S. aegyptiacus and 1.5 in S. maroccanus. Later authors have been split on this topic. Some authors note that the length of the vertebrae can vary from individual to individual, that the holotype specimen was destroyed and thus cannot be compared directly with the S. maroccanus specimen, and that it is unknown which cervical vertebrae the S. maroccanus specimens represent. Therefore, though some have retained the species as valid without much comment, most researchers regard S. maroccanus as a nomen dubium or as a junior synonym of S. aegyptiacus.
Spinosaurus was estimated to grow lenghts between 12 - 18m. The largest specimen of S. aegyptiacus measured 15 meters (49 feet) in length, 4 meters (13 feet) in height at the head and 6.9 tonnes (7.6 tons). It's mouth had a similar appearance to that of the Irritator & Suchomimus (crocodile-shaped).
It got its name, which means "spine lizard," because of the tall spines on its vertebrae (bones of the spine), some reaching a height of six feet; which created a sail structure along the dorsal edge of the animal.
The enlarged vertebrae of Spinosaurus that give it its name have been a cause of a great deal of controversy in recent years, with some people claiming they were a shrink-wrapped sail akin to Dimetrodon or Edaphosaurus, and others arguing instead that it was a thick ridge or hump akin to a bison or rhinoceros. The remains published in 2014 have shown that the vertebral spines narrow at the top nearer the front end of the animal, which means they would not have supported a thick fatty hump, however, they still do not display the characteristics of a “true sail-back” either. There were "few channels for blood vessels" meaning it likely wasn't for thermal regulation. Sail-backed reptiles have the supports for their sails that are thin, almost like the rays of a fishes fins, this can be seen for example in modern basilisks, whereas the vertebrae of Spinosaurus are thick at the base and narrow towards the top. In life the structure would have appeared rising from the body to form a triangular shape over the animals back (when viewed from in front), as opposed to either a shrink-wrapped sail or a large hump, it would have been most akin to chameleons. However, the vertebrae towards the animal's hips were thicker and could have supported a hump, perhaps to aid in buoyancy or balance.
Spinosaurus' primary weapons are its 5 foot arms with 25-30cm fingers armed with 15-20cm claws, designed for wrestling and slashing fish and other large prey, and its jaws. In a defensive scenario, Spinosaurus' arms would be capable of crudely swiping (most theropods arms were deeply locked in their shoulder sockets) at its attacker(s), however they would work far more effectively when used to grapple its attacker(s) to immobilize them in order to land a thrashing bite. Its secondary weapon, its 1.6-meter jaws, would have been highly effective at grabbing prey and or rivals due to the conical, non-serrated teeth. The teeth were hollow, meaning it had a relatively weak bite compared to other predators.
Spinosaurus is thought to be a semi-aquatic animal. Believed proof of this is the elongated feet, hydrodynamic design, and small holes on the top of its snout, much like the electroreceptors of a shark or alligator. Further evidence was found in 2010 when an isotope analysis by Romain Amiot and colleagues found that oxygen isotope ratios of spinosaurid teeth, including teeth of Spinosaurus, indicate semiaquatic lifestyles.
Isotope ratios from tooth enamel and from other parts of Spinosaurus and of other predators from the same area such as Carcharodontosaurus were compared with isotopic compositions from contemporaneous theropods, turtles, and crocodilians.
The study found that Spinosaurus teeth from five of six sampled localities had oxygen isotope ratios that are 'closer' (albeit Not the same/similiar) to those of turtles and crocodilians when compared with other theropod teeth from the same localities. The authors postulated that different genera of spinosaurids would've had different habitat preferences. Along with that the Spinosaurus likely switched its living/hunting Territory between terrestrial and aquatic habitats for food during the droughts and dry seasons of its ecosystem. This strongly suggested that the Spinosaurus has more amphibious (lives both land and water) lifestyle rather than a fully aquatic lifestyle.The shape of the skulls show that Spinosaurus is similar to Baryonyx and Suchomimus. They are both parts of the group Spinosauridae, but Spinosaurus belongs to a sub-group known as Spinosaurinae, while Baryonyx belongs to a separate group known as Baryonychinae, which have different features among their members.
Spinosaurus is believed to have eaten aquatic-water based prey such as large fish and crocodyliomorphs, but in times of famine and drought which were common, it would be more than capable of hunting small to medium prey such as juvenile and subadult Aegyptosaurus, Deltadromeus, Rugops and scavenging off of Carcharodontosaurus. Direct fossil evidence from several of its relatives (Irritator teeth on a large pterosaur, Siamosaurus remains with direct relation with sauropod fossils; Baryonyx gut contains both fish and Iguanadon remains); indicate that spinosaurs were very likely a generalist apex carnivore that ate any prey item available; whether aquatic or terrestrial, rather than being purely piscivorous.
A new study challenging the theory that Spinosaurus was semiaquatic has been published, however there are many faults within the study. Firstly, the study did not account for behaviors such as stone swallowing, which would greatly aid in diving and buoyancy. Secondly, the study incorrectly came to a conclusion about the density of the animal, calculating its volume based on other animals such as Tyrannosaurus and ostriches, instead of using pre-calculated volume estimates. Lastly, the 3D model used to simulate Spinosaurus swimming was far too thin compared to the real animal in life, and greatly hindered the accuracy of the study.
In the Media
- Spinosaurus has become an iconic dinosaur and its fame started with the film, Jurassic Park III, the first Jurassic Park film not based on a Michael Crichton book. Spinosaurus was portrayed as the main "villain" that caused destruction in its path. In an infamous scene, this Spinosaurus was seen fighting a Tyrannosaurus rex and defeating it. A Spinosaurus fossil Skeleton was seen in Jurassic World where it was destroyed by the Tyrannosaurus Rexy during the Isla Nublar Incident of 2015. It is also one of the dinosaurs included in the Holoscape of Innovation Center, though it is unknown if Spinosaurus actually lives in Jurassic World. Spinosaurus also apparently into cruelty after the Isla Nublar Incident of 2015 before Jurassic World: Fallen Kingdom, on Isla Nublar, though it's unknown if there were any surviving populations left. However, it was planned to be in Jurassic World: Fallen Kingdom having a rematch with the T. rex before being cut from the film entirely. Spinosaurus also appears in most of the Jurassic Park expanded universe, including games and toy lines.
- Spinosaurus also appears in many video games such as Jurassic Park: Operation Genesis, Zoo Tycoon, Carnivores 2, and much more. It is also popular as a player made animal in "Zoo Tycoon 2."
- Spinosaurus appears in the video game Carnivores 2, with an inaccurate anatomy because in the epoch there was little information about this dinosaur.
- Spinosaurus appears in series 4 of Primeval and is shown living in the same place as a Raptor (Dromaeosaur). Another one appears in Series 5.
- Spinosaurus is also in the Discovery Channel's Monsters Resurrected, portrayed as the "Biggest Killer Dino", where it was inaccurately shown to be the super top predator on land. It was seen lifting up and consuming a Rugops whole, kill a Carcharodontosaurus with a single slash of its claws, and slice up the sides of Sarcosuchus. But at the end, it was brought down by a pack of 5 Rugops. The portrayal was noticeably over-powered compared to the real dinosaur.
- A Spinosaurus, nicknamed "Spike", makes an appearance in the video game Jurassic: The Hunted, appears as a boss.
- Spinosaurus appears in National Geographic's Bizarre Dinosaurs, where its sail is talked about. The same Spinosaurus model was briefly seen in another National Geographic Documentary Dinomorphosis.
- Spinosaurus appears in the Japanese animated film Doraemon: Nobita's Dinosaur 2006, where it is the abused pet of an evil time-traveling dinosaur poacher. Also, near the climax, Spinosaurus faces off with Tyrannosaurus only to be defeated.
- Spinosaurus appears in the first episode of BBC's Planet Dinosaur as a fish hunter and during the drought shown to hunt land animals if there are no aquatic animals to eat (no animal eats one thing being an opportunist spinosaurus would likely eat whatever it could), At one of the remaining pools a Sarcosuchus awaken from its hibernation & warded off the Spinosaurus and then resumed hibernation. It later competes against a Carcharodontosaurus for an Ouranosaurus carcass and defeats it in battle with its claws. The same Spinosaurus model was seen in two other Documentaries PBS's Nova National Geographic Special Documentary Bigger Then T.REX & Top 10 Biggest Beasts Ever from Nat. Geo. Wild AKA World's Biggest Beasts from The Smithsonian Channel. Only it was in different color appearances in the other two documentaries.
- It also is a playable character in Primal Carnage.
- Spinosaurus also appears in the 12th episode of The Land Before Time but is inaccurately shown with only two fingers. It was also a minor antagonist in the film.
- A Spinosaurus makes a brief appearance in the Asylum film Age of Dinosaurs where it was running around the city with the rest of the escaped Dinosaurs & somehow is able to climb on top of a tall building.
- Spinosaurus appears in the game Jurassic World: Evolution. It is based off the Jurassic Park III variant.
- In Fossil Fighters series, Spinosaurus is a playable vivosaur.
- Spinosaurus was the main character in Ricardo Delgado's Age of Reptiles: Ancient Egyptians mini-series.
- The dinobot Scorn of Transformers: Age of Extinction, the decepticon Undermine and his autobot copy Repugnus of Transformers: Cybertron all turn into a mechanical version of Spinosaurus.
- The spinosaurus appears in ARK: Survival Evolved as one of the tameable creatures.
- The Spinosaurus appears in the game Parkasaurus.
- Spinosaurus appears in the ROBLOX game "Era of Terror: Remastered", like the other dinosaurs in the game, it starts off as a juvinile then grows into an adult, taking about 40 real life minutes to complete a growth stage.