Stegosaur tails packed a punch
By Sid Perkins
From Norman, Okla., at a meeting of the Society of Vertebrate Paleontology
A mathematical analysis of a fossil stegosaur’s bones leaves little doubt that the creature’s spike-studded tail was an effective defense against predators.
Stegosaurus stenops was a 9-meter-long, 2-ton herbivore that had two rows of finlike plates running along its back and two pairs of meter-long spikes adorning its tail. Those pointy skewers, wrist thick at their base, projected backward and almost horizontally from the sides of the tail at angles of about 35 and 60, says Frank Sanders of the Denver Museum of Natural History. The slightly flattened spikes were covered with keratin, the same protein found in horns, fingernails, and claws.