The African crested porcupine (Hystrix cristata) is the largest porcupine in the world. The black and white quills along the head and back of this spiny mammal can be raised into a crest, hence its common name of crested porcupine. These sturdy, sharp quills, which are about 35 centimetres long and marked with alternating light and dark bands, provide highly effective protection against predators. The underside of the crested porcupine’s short body is covered in rough dark-brown or black bristles. It has thick legs, with four well-developed, clawed digits on its forefeet and five digits on its hindfeet. Its eyes and ears are very small. Porcupine species in the genus Hystrix are distinct from porcupines in other genera in having a shorter tail that bears special quills at the end. These tail quills are broad, thin-walled and hollow at the tip, so that when vibrated, such as when the animal is threatened or aggressive, they produce a hiss-like rattle.