Diplodocus is one of the most famous long-necked dinosaurs. At over 88 ft long from the tip of its snout to the end of its whip-like tail, Diplodocus is as long as three buses. This ground-shaking plant eater occupied North America during the Late Jurassic, about 153 million years ago.

This well-known, long-necked dinosaur was named in 1878. Many Diplodocus skeletons are known from the Jurassic deposits of Colorado, New Mexico, Utah, and Wyoming. Some early reconstructions wrongly portrayed Diplodocus in a sprawling posture, but this would have required a trench in the ground to accommodate its deep chest.

Diplodocus was a plant eater that had a tiny skull relative to the size of its giant body, as this Diplodocus toy reflects. It had simple, peg-like teeth for stripping leaves, a long neck, and an especially long whip-like tail. Diplodocus walked on all fours and its front feet had a single claw on the thumb. A row of soft, triangular spines may have extended along the top of its neck, back, and tail.