Majungasaurus crenatissimus - The Jurassic World Cannibal

Majungasaurus is a medium-sized carnivorous theropod - about 20 feet long and about 1 ton in weight - having inhabited the African island of Madagascar during the Upper Cretaceous period. As a ceratosaur, Majungasaurus has the typical look found in other predators of this branch such as Ceratosaurus and Abelisaurus: it has a crouching and more horizontal posture than those of Tetanurans.

Majungasaurus is easily distinguishable from other ceratosaurs because it has a blunt snout and a single little horn or bump on the top of its skull. This bump has also led paleontologists who found the first vestiges to erroneously conclude that they were dealing with a pachycephalosaurus. It was not until other better conserved fossils started showing up that it was identified for what it actually was, a ceratosaur theropod.

Cannibal predator

This dinosaur is frequently associated with cannibalism as portrayed in the film Jurassic World where the cannibal behavior of Indominus Rex is attributed to the genome of Majungasaurus. Bite marks belonging to Majungasaurus were found on bones also belonging to Majungasaurus. However, it is impossible to say whether these bites are the result of intraspecies hunts, which is rather rare to observe in nature and which would confirm the cannibalistic nature of Majungasaurus, or if this dinosaur was occasionally scavenger when preys were scarse. Regardless, it is important not to believe that cannibalism is the exclusive attraction of Majungasaurus since similar evidence also exists for other theropod species such as Tyrannosaurus and Allosaurus.

Respiratory system similar to modern birds

Studies that have targeted Majungasaurus vertebrae have revealed that this dinosaur has a respiratory system very similar to that of modern birds. Empty spaces in the vertebrae allow the inclusion of small air pockets that increases the amount of oxygen available for breathing.

The implications of evolutionary nature are significant since the Tetanurans, and more precisely the raptors, are suspected to be the ancestors of modern birds. Convergent evolution is possibly at cause for this characteristic found in two different lines of theropods that descend from the same common ancestor or was it already present before the division occured. Be that as it may, it is overwhelming evidence that the bird's respiratory system is of dinosaurian origin, which only reinforces the theory that birds descend from dinosaurs.

Very slow growth

Apex predator of the Madagascar region, one wonders why the Majungasaurus reached relatively small sizes for such a theropod. This dinosaur had an exceptionally slow growth when compared with other large theropods such as the T Rex or Albertosaurus. Majungasaurus crenatissimus took more than 20 years to reach adult size, one of the slowest growths in the dinosaurs' reign.

Laboratory analysis performed on eight bones obtained using a rock saw confirmed it. By observing the growth lines of Majungasaurus bones under the microscope, researchers noticed that this dinosaur was growing at an unusually slow rate. This is undoubtedly due to the harsh environmental conditions of Madagascar characterized by frequent droughts and floods.