Tenontosaurus

dinosaur · early cretaceous · ornithopod · north america

Incredibly long tail. Tenontosaurus had an unusually long, broad tail that made up a huge part of its body. This tail wasn't just floppy like a lizard's tail because it had a special network of bony tendons running through it, like built-in support beams.

Bony internal scaffold. Instead of relying on just bone and muscle, Tenontosaurus used a network of bony tendons to stiffen both its back and tail. These tendons acted like internal struts that kept everything rigid and strong during movement.

Ancient time traveler. Tenontosaurus lived during the Early Cretaceous period between 115 and 108 million years ago. This was a time when many different dinosaurs roamed the planet, and Tenontosaurus was an iguanodontian, a group of two-legged plant-eating dinosaurs.

Western North American resident. Fossils of Tenontosaurus have been found across western North America, especially in geological formations from that ancient era. One species, T. dossi, is known from only a few specimens found in Texas, making it rarer than its cousin T. tilletti.

Two species discovered. Scientists have identified two species of Tenontosaurus: T. tilletti and T. dossi. T. tilletti is much better known because many more complete skeletons have been found of this species across different formations.