Movies - Spinosaurus

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Spinosaurus ("spine lizard") was a theropod dinosaur genus that lived in what is now Egypt from the Albian to early Cenomanian stages of the Cretaceous period, about 95 to 93 million years ago. According to a study by dal Sasso et al. (2006), it was the largest of all carnivorous dinosaurs by a significant margin, larger even than Tyrannosaurus rex
. Spinosaurus is the longest known theropod, measuring 16 to 18 metres (52 to 60 feet) long. Spinosaurus reached weights up to 9 tons, though further comparisons with related species suggest that adults could have reached sizes up to 20 tons and 21 m (70 ft) in length. The distinctive spines of these animals (large bones extending from the vertebrae) grew up to 2 m long and likely had skin stretching between them, forming a sail-like structure, though some have suggested they were covered in muscle and formed a hump or ridge. Spinosaurus provides the name of a family of dinosaurs, the Spinosauridae, of which other members include Angaturama (probably synonymous with Irritator), Baryonyx
, Irritator, Suchomimus, and Siamosaurus.

Description

Although Spinosaurus is well-known to dinosaur enthusiasts because of its unusual features, it is mostly known from remains that have been destroyed, aside from a few more recently discovered teeth and skull elements. Jaw and skull material published in 2006 show that it had one of the longest skulls of any carnivorous dinosaur, estimated by dal Sasso et. al. at about 175 cm (5.7 ft). Originally found in the Bahariya Valley of Egypt in 1912, it was named by German paleontologist Ernst Stromer in 1915. Some of the fossils were damaged during transport back to the Munich Museum in Germany, and the remaining bones were completely lost due to Allied bombing in 1944.

Aside from its sail, notable characteristics of Spinosaurus include:

A long, narrow snout similar to other Spinosaurids, and like them filled with conical teeth.
One enlarged, hook-like claw on each of its front limbs, perhaps for catching fish.
Relatively short legs and long arms, leading some paleontologists to suggest it may have been quadrupedal, rather than strictly bipedal (though it was undoubtedly capable of at least facultative bipedality).

Much of this is speculation based on Baryonyx and other spinosaurids, as no limb material has ever been attributed to Spinosaurus itself.

Diet

It is unclear whether Spinosaurus was a cursorial predator or a fisher, as indicated by its elongated jaws, conical teeth and raised nostrils. The only direct evidence for spinosaur diet comes from related European and South American species. Baryonyx
was found with both fish scales and bones from juvenile Iguanodon in its stomach, while a tooth embedded in a South American pterosaur bone suggests that spinosaurs occasionally preyed on these flying archosaurs. Spinosaurus was likely a more generalized and opportunistic predator, possibly a Cretaceous equivalent of large grizzly bears, being biased toward fishing, though it undoubtedly took many kinds of small to medium sized prey in general.

Sail

Spinosaurus sails were unusual, although other dinosaurs of the same time and area, namely the ornithopod Ouranosaurus and the sauropod Rebbachisaurus, developed a similar structure of their dorosal vertebrae. The sail is possibly analogous (not homologous) to that of the Permian mammal-like reptile, Dimetrodon, which lived before the dinosaurs even appeared (these similarities are presumably due to parallel evolution).

The purpose of these sails is uncertain; scientists have proposed several hypotheses:

Heat regulator. If the sail contained abundant blood vessels, the animal could have used its large surface area to absorb heat. This would imply that the animal was only partly warm-blooded at best and lived in climates where nighttime temperatures were cool or low and the sky usually not cloudy. It is thought that Spinosaurus and Ouranosaurus both lived in or at the margins of an earlier version of the Sahara Desert, which could explain this. It is also possible that the sail was used to radiate excess heat from the body, rather than to collect it. Large animals, due to the relatively small ratio of surface area of their body compared to the overall volume (Haldane's principle), face far greater problem of losing excess heat at higher temperatures than gaining it at lower. Sails of these dinosaurus added considerably to the skin area of the body with minimum increase of volume; furthermore, if the sail was turned away from the sun, or positioned at a 90 degree angle towards a cooling wind, the animal would quite effectivly cool itself in the warm climate of Cretaceous Africa.
Sexual display. Elaborate body structures of many modern-day animals usually serve to attract members of opposite sex during mating. It is quite possible that the sails of these dinosaurus were used for courtship, in a way similar to peacock's tail. If this was the case, the sails may have been brightly colored, but this is pure guesswork.
Intimidating device. The sail was possibly used to intimidate rivals or frighten enemies, making the animal look bigger than it was. The dinosaur could display its sail as a final warning signal before it would resort to open attack, like modern-day rattlesnakes use their tail.

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Movies - Spinosaurus

Description

Diet

Sail

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