Quasimodo revealed among the dinosaurs

Herbivorous Nigersaurus had a vacuum cleaner snout and shark teeth

Nigersaurus taqueti - skeleton and reconstruction © Tyler Keillor / Mike Hettwer, courtesy of Project Exploration, National Geographic
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He has a mouth like a vacuum cleaner, hundreds of tiny sharp teeth, paper-thin skull and vertebral bones and is 110 million years old - the Nigersaurus taqueti. New details about this anatomically extremely bizarre dinosaur and its way of life have now been revealed by American scientists.

Paul Sereno, paleontologist at the University of Chicago and his colleagues discover the dinosaur's fossil relics in 1997 on an expedition to the Sahara on the Niger. Since then, they managed to recover about 80 percent of the skeleton. The first finds of a Nigersaurus made in the 1950s French paleontologists, but since it was only isolated bones, little could be learned about the animals, the species was therefore not even then called.

Anatomical "special model"

Meanwhile, however, thanks to the almost complete skeleton, it is clear that Nigersaurus taqueti must have been an anatomically extremely strange being: As a younger cousin of Diplodocus the herbivore measured only about nine feet from the head to the tail. His clumsy, elephant-sized trunk was crowned by an extremely small and light skull. Barely able to raise his head above shoulder height, he looked more like a Mesozoic cow than a giraffe-like reptile.

The most bizarre part of the dinosaur, however, was its broad, straight-down snout, which was perfectly adapted to the grazing of the low plant cover. As Sereno and his co-authors report in the journal "PLOSOne", such a muzzle could characterize most diplodocoids. "Some of these unusual sauropods became the dominant pastoralists of the Mesozoic, " said Jeffrey Wilson, assistant professor at the University of Michigan.

50 rows of teeth with hundreds of replacement teeth

Unlike all other herbivores, Nigersaurus not only had a few strong molars, but 50 rows of razor-sharp teeth, all lined up close to each other along the front of his jaw. They basically formed a sharp, 30-centimeter-long pair of scissors. display

Nigersaurus taqueti - Art Narrative Todd Marshall, courtesy of Project Exploration, National Geographic

Computed tomography of the bones showed that behind each incisor, up to nine replacement teeth were waiting to be used, similar to modern sharks. If one failed, this replacement came directly in its place. Overall, the Nigersaurus came with more than 500 teeth, every month, each row grew by one tooth. "Among the dinosaurs, Nigersaurus clearly has the Guiness record for dentures, " Sereno said.

Vertical head and paper-thin vertebrae

The CT scan also confirmed to the researchers that the dinosaur was usually holding its head and muzzle perpendicular to the ground. The alignment of tiny channels in the balance organ revealed this. "What we have here is the first accurate look into a sauropod brain, " explains Lawrence Witmer, a professor at the University of Ohio who did the scans. "He tells us important things about the attitude and behavior of this animal."

But the jaw was far from the only bizarre feature of the Nigeraurus. The examination of the bones revealed that, surprisingly enough, the great animal had a spine that consisted almost more of air and bone. "The whirls are so paper-thin that it's hard to imagine how they coped with the burdens of everyday use, " said Wilson. But we know that they succeeded and that's good.

(Public Library of Science, 16.11.2007 - NPO)