Predatory Dinosaur Irritator Had Evolutionary-Shaped Skulls Allowing for Weak but Very Fast Bite, Jaws That Worked Like Pelicans’

Irritator challengeri, a predatory dinosaur, had a surprising anatomy. Apparently, it had jaws that worked like the pelicans and an evolutionary-shaped skull.

Irritator Challengeri's Anatomy

Irritator challengeri, discovered in about 115 Ma, is the spinosaurid fossil skull, the sedimentary strata from eastern Brazil. Paleontologists also discovered bones from other dinosaurs, pterosaurs, relatives of crocodiles, turtles, and various fish species.

The species was a spinosaurid, estimated to have reached a body length of about 6.5 m, representing the largest animal in its ecosystem, Phys.org reported.

To determine what makes spinosaurids unique, the researchers' most recent work involved reconstructing each skull bone from the fossil and placing them together in their original positions. They discovered using CT data that Irritator held its snout at an angle of about 45° when it needed to pay close attention to its surroundings. Since there were no obstructions to the field of vision being produced by both eyes, such as the long muzzle, this position allowed for a three-dimensional area of vision to the front.

A somewhat weak but quick bite was also produced by the evolutionarily formed skull of the Irritator. When this predator opened its mouth, the lower jaws extended out to the sides, widening the pharynx because of the form of the lower jaw joint. This is accomplished through many biomechanical processes and is somewhat reminiscent of the behavior of pelicans.

These are clues to Irritator's fondness for small prey items, such as fish, which were quickly grabbed and severely wounded with quick jaw motions to swallow them whole quickly.

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More About Irritator Dinosaur

Irritator is a spinosaurid, or two-legged, meat-eating dinosaur. The most complete fossil skull from this group known to science serves as the basis for understanding the species.

Paleontologists from Greifswald, Munich (both in Germany), Alkmaar (Netherlands), and Fribourg (Switzerland) meticulously examined the fossil. They made astounding discoveries with the use of X-ray computed tomographs, which are often utilized in the context of medicine or material research.

Irritator is thought to have hunted relatively small prey with a sharply slanted snout that evolved to close swiftly in what is now Brazil. The lower jaws of the hunter stretched its muzzle, extending the area around the throat, which surprised the specialists much.

The peculiar spinosaurus' moniker represents its peculiar origin story. as stated in David Martill and colleagues' 1996 description of the dinosaur. Before being bought and entering the collection of Germany's Stuttgart State Museum of the Natural Sciences, the mainly complete skull of Irritator had undergone artificial modification by a commercial fossil dealer.

Blocks of matrix were taken from other parts of the specimen, and a thick Isopon car body filler covered the bone from another area of the skull that made up the snout's tip. In addition to misleading the customers, the fake fossil was particularly challenging to separate from the real one. As a nod to the feeling the authors experienced upon learning that the snout had been artificially lengthened, Martill and colleagues gave the dinosaur the name Irritator, according to Smithsonian Magazine.