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For most of its history, Earth’s skies were ruled by giants with jaws full of sharp teeth. Yet the 105‑million‑year‑old Nigersaurus taqueti was a gentle herbivore, sporting an astonishing 500 teeth. Its skull resembles a modern binder clip, and the straight rows of teeth are a hallmark that puzzled scientists for decades.
Nigersaurus—pronounced “nee‑zhay‑r‑sore‑us”—derives its name from Niger, the country where the first bones surfaced in the 1960s. Though the fossils were discovered early, the sheer volume of material meant it took 30 years before the species was formally recognized.
Paleontologist Paul Sereno, who led the team that described the species, was initially struck by the jaw’s unusual shape and even considered a coelacanth fish as a possibility. CT scans, however, revealed a surprising detail: each jaw bore rows upon rows of teeth, totaling more than 500.
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Both the upper and lower jaws of Nigersaurus contained roughly 60 thin, needle‑like teeth. While 60 teeth per jaw might suggest only 120 teeth, the reality is far more complex. CT imaging uncovered that each tooth was part of a column, or “dental battery,” consisting of 5 to 10 individual teeth stacked vertically. This arrangement allowed Nigersaurus to replace worn teeth rapidly.
With an estimated replacement cycle of just two weeks, Nigersaurus boasted the fastest tooth turnover among known dinosaurs. The mechanism worked like a conveyor belt: as the outer teeth wore down, the next tooth in the column rose to replace it, while a new tooth formed at the base.
Why such rapid replacement? In the Cretaceous, grasses had not yet evolved. Nigersaurus fed on silica‑rich plants like horsetails, which wore down teeth quickly, demanding a constant renewal cycle.
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As a sauropod, Nigersaurus shared a long neck and massive body with better‑known relatives such as Brontosaurus, Brachiosaurus, and Diplodocus. Yet it was a black sheep: at only about 30 feet long and just over four tons, it was comparable to an elephant—much smaller than the giants of its era, such as Patagotitan.
Its shorter neck meant it couldn’t reach treetops, leading to a unique grazing strategy and jaw morphology. Like other sauropods, Nigersaurus had hollow, air‑filled bones that reduced body weight, allowing it to move efficiently despite its size.
Unfortunately, the fragile nature of these bones has complicated studies, leaving many aspects of this remarkable dinosaur still shrouded in mystery.
