91. Our final theropod for #TheSummerOfTheropods, #Spinosaurus (spine lizard), a large spinosaurid from the Cretaceous Period of North Africa, and arguably the most enigmatic theropod. Similar to the last two theropods, this’ll be a long thread. Art by Gustavo Monroy-Becerril
The original remains of Spinosaurus were discovered and described by German paleontologist Ernst Stromer.
Despite being incomplete, the original material of Spinosaurus consisted of the dentaries, teeth, cervical vertebrae, dorsal vertebrae, sacral vertebrae, caudal vertebra, thoracic ribs, and gastralia.
The longest of the neural spines for the dorsal vertebrae measured 1.65 meters (5.4 ft) in length.
The original specimen of Spinosaurus was destroyed in WWII, during a British bombing raid of Munich. Fortunately new material of Spinosaurus was recovered, some giving new light into the appearance of Spinosaurus. Image by @NatGeo.
Originally Spinosaurus was depicted with a typical Tyrannosaurus-like head, in an upright kangaroo posture along with the sail on its back. Skull bones belonging to Spinosaurus later showed that it more resembled Baryonyx, as opposed to having deep, boxy skull.
Originally Spinosaurus was depicted with a typical Tyrannosaurus-like head, in an upright kangaroo posture along with the sail on its back. Skull bones belonging to Spinosaurus later showed that it more resembled Baryonyx, as opposed to having deep, boxy skull.
Originally Spinosaurus was depicted with a typical Tyrannosaurus-like head, in an upright kangaroo posture along with the sail on its back. Skull bones belonging to Spinosaurus later showed that it more resembled Baryonyx, as opposed to having deep, boxy skull.
Spinosaurus’ skull was 1.75 meters (5.7 ft) long, with a long, narrow snout filled with straight conical teeth that lacked serrations. The skull and teeth of Spinosaurus suggested that it was piscivorous and had a diet consisting of fish, but may have fed on other animals.
More material revealed Spinosaurus as the largest among all known carnivorous dinosaurs nearly as large as or even larger than Tyrannosaurus, Giganotosaurus and Carcharodontosaurus. Estimates suggested that it was between 12.6–18 meters (41–59 ft) in length and 7 tons in weight.
Credit to Franoys, Slate Weasel, and @skeletaldrawing.
The most impressive feature of Spinosaurus was its spines, which may have formed either a sail or a hump. It may have served for heat regulation and display, in addition, to possibly making it appear even larger than it was, intimidating other animals. Art by @MarkWitton
These were the two most discernible features of Spinosaurus, prior to the 2014 and 2020 study. In 2014 and 2020, Spinosaurus received a “makeover”.
These were the two most discernible features of Spinosaurus, prior to the 2014 and 2020 study. In 2014 and 2020, Spinosaurus received a “makeover”.
These were the two most discernible features of Spinosaurus, prior to the 2014 and 2020 study. In 2014 and 2020, Spinosaurus received a “makeover”.
In 2014, Spinosaurus' hip bones were reduced, and the legs were very short in proportion to the body, suggesting that it was poorly adapted for bipedal terrestrial locomotion and may have been an obligate quadruped on land. Art by
Davide Bonadonna
In addition, Spinosaurus may have been adapted to a semi-aquatic lifestyle. Art by Davide Bonadonna
In addition, Spinosaurus may have been adapted to a semi-aquatic lifestyle. Art by Davide Bonadonna
In addition, Spinosaurus may have been adapted to a semi-aquatic lifestyle. Art by Davide Bonadonna
This depiction of Spinosaurus, however, has been met with skepticism as it may have been unable to dive and completely submerge itself underwater. Image from a 2018 study by Donald Henderson of @RoyalTyrrell.
In 2020, recent studies have refuted the skepticism where Spinosaurus’ tail vertebrae had elongated neural spines and chevrons where it would have resembled an eel’s tail indicating that Spinosaurus was able to swim in a similar manner to modern crocodilians.
As for the tiny legs, biomechanics have shown that Spinosaurus was probably competent at bipedal terrestrial locomotion, as the center of mass was found to be close to the hips, allowing it to stand upright like other bipedal theropods. Art by @MarkWitton.
Spinosaurus lived in a shoreline environment with tidal flats and channels, possibly living in mangrove forests. Art by Davide Bonadonna.
Spinosaurus lived in a shoreline environment with tidal flats and channels, possibly living in mangrove forests. Art by Davide Bonadonna.
Spinosaurus lived in a shoreline environment with tidal flats and channels, possibly living in mangrove forests. Art by Davide Bonadonna.
It also lived alongside alongside similarly large dinosaurian predators Bahariasaurus and Carcharodontosaurus, the titanosaur sauropods Paralititan and Aegyptosaurus, crocodylomorphs, bony and cartilaginous fish, turtles, lizards, and plesiosaurs. Artwork by Davide Bonadonna.
It also lived alongside alongside similarly large dinosaurian predators Bahariasaurus and Carcharodontosaurus, the titanosaur sauropods Paralititan and Aegyptosaurus, crocodylomorphs, bony and cartilaginous fish, turtles, lizards, and plesiosaurs. Artwork by Davide Bonadonna.
It also lived alongside alongside similarly large dinosaurian predators Bahariasaurus and Carcharodontosaurus, the titanosaur sauropods Paralititan and Aegyptosaurus, crocodylomorphs, bony and cartilaginous fish, turtles, lizards, and plesiosaurs. Artwork by Davide Bonadonna.
It also lived alongside alongside similarly large dinosaurian predators Bahariasaurus and Carcharodontosaurus, the titanosaur sauropods Paralititan and Aegyptosaurus, crocodylomorphs, bony and cartilaginous fish, turtles, lizards, and plesiosaurs. Artwork by Davide Bonadonna.
It also lived alongside alongside similarly large dinosaurian predators Bahariasaurus and Carcharodontosaurus, the titanosaur sauropods Paralititan and Aegyptosaurus, crocodylomorphs, bony and cartilaginous fish, turtles, lizards, and plesiosaurs. Artwork by Davide Bonadonna.
As for popular culture, Spinosaurus’ main appearance was in the film Jurassic Park III as the main villain of the film and was prominently featured fighting and killing the Tyrannosaurus, thus leading to numerous “versus matchups” between Spinosaurus and Tyrannosaurus.
As for popular culture, Spinosaurus’ main appearance was in the film Jurassic Park III as the main villain of the film and was prominently featured fighting and killing the Tyrannosaurus, thus leading to numerous “versus matchups” between Spinosaurus and Tyrannosaurus.
As for popular culture, Spinosaurus’ main appearance was in the film Jurassic Park III as the main villain of the film and was prominently featured fighting and killing the Tyrannosaurus, thus leading to numerous “versus matchups” between Spinosaurus and Tyrannosaurus.
Despite the constantly changing appearance, Spinosaurus has remained a very popular theropod and dinosaur, and a perfect way to end off #TheSummerOfTheropods. Art by MALvit.
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