English: This specimen is a cast of Diplodocus fossil teeth in matrix. A Diplodocus is a herbivorous dinosaur with an extremely long neck and body from the Late Jurassic (163.5 to 145 million years ago). On average, a Diplodocus measured 30 meters long and weighed around 15 tons. This cast of fossilized teeth were part of a set of 20-30 teeth located only at the front of the dinosaur's upper and lower jaw. These dinosaurs used their peg-like teeth to eat massive amounts of soft aquatic vegetation. Due to continual chomping on vegetation, this dinosaur frequently developed one new tooth about every 35 days to replace an old worn down tooth.