The dental adaptations of dinosaurs were remarkably diverse, reflecting their varied diets and ecological roles. Among these adaptations, some dinosaurs developed an astonishing number of teeth, a specialized feature allowing them to thrive in their specific environments.
The Dinosaur with 500 Teeth
The dinosaur known for its extraordinary number of teeth is Nigersaurus taqueti, a rebbachisaurid sauropod that lived 110-115 million years ago during the Early Cretaceous period. This plant-eating dinosaur was relatively small for a sauropod, measuring about 9 meters (30 feet) long and weighing between 1.9 to 4 metric tons, comparable to a modern elephant. Its most distinctive feature was its skull, which had a wide, straight-edged muzzle that resembled a vacuum cleaner or shovel. This broad muzzle housed over 500 teeth. Nigersaurus was discovered in what is now the Sahara Desert in Niger, the country from which it derives its name.
A Grazing Specialist’s Dental Toolkit
The multitude of teeth in Nigersaurus’s mouth formed a “dental battery”—a complex arrangement of active and replacement teeth. Each tooth column contained up to nine replacement teeth stacked beneath the active one, ready to erupt. This continuous replacement meant teeth were worn down and replaced at an exceptionally rapid rate, estimated as often as every 14 days—the highest known replacement rate for any dinosaur. This rapid turnover was important for its diet of low-lying vegetation like ferns, horsetails, and early flowering plants, as grass had not yet evolved during its time. The wide, shovel-shaped muzzle and the lateral orientation of its tooth rows suggest Nigersaurus grazed with its head close to the ground, sweeping side-to-side to efficiently crop large quantities of plant material.
How Paleontologists Reconstruct Ancient Mouths
Paleontologists reconstruct the dental features of extinct animals by studying fossilized remains. They examine fossilized skulls, jaw fragments, and individual teeth to understand the structure and function of ancient mouths. The number of teeth and their arrangement in a dental battery are revealed through careful analysis of these fossil components. Advanced imaging techniques, such as Computed Tomography (CT) scans, are valuable in this process. CT scans allow researchers to peer inside fossilized jaws without causing damage, revealing hidden rows of unerupted replacement teeth and providing a detailed, three-dimensional view of the dental battery. This helps scientists understand how these complex systems functioned and adapted to feeding habits.