Hystricidae (Old World porcupines) Erethizontidae (New World porcupines)
Porcupines are rodents with a coat of sharp spines, or quills, that defend them from predators. They are indigenous to the Americas, Southern Asia, Europe, and Africa. Porcupines are the third largest of the rodents, behind the capybara and the beaver. Most porcupines are about 25–36 in (64–91 cm) long, with an 8–10 in (20–25 cm) long tail. Weighing 12–35 lb (5.4–15.9 kg), they are rounded, large and slow. Porcupines come in various shades of brown, gray, and the unusual white. Porcupines' spiny protection resembles that of the unrelated erinaceomorph hedgehogs and monotreme echidnas.