Old World Porcupines: Hystricidae

The Old World (living in Africa, Asia, and Europe) porcupines (called "quill pigs" in Latin) take their English name from the formidable spines, quills, and bristles that cover their sides, back, and tail. Their heads and bodies together range in length from between 13.8 to 36.6 inches (35 to 93 centimeters) and the animals usually weigh between 3.3 to 66.1 pounds (1.5 to 30 kilograms). The eleven species fall into three genera ( JEN-uh-ruh; plural of genus): Hystrix, the Old World porcupines; Trichys, which are more slender mammals with flatter, shorter, and less-developed quills; and Atherura, which includes the brush-tailed porcupines. Most of the species have short tails, but others can have tails up to half of their head-body length. Eyes are usually small and can see only poorly, but the mammals' small ears are very keen. Nostrils are often S-shaped and contribute to a strong sense of smell.

Species in the Hystrix genus ( JEE-nus) are stocky, somewhat lumbering animals with rounded, blunt heads; mobile, fleshy noses; split upper lips; and coats of thick flattened or cylindrical spines. The mammals stay on the ground at all times, never venturing into trees like their cousins, the New Age porcupines of North America. Hystrix alone among the porcupines has chambers in its skull that can be inflated, possibly to increase the ability to smell underground food sources. This slow-moving genus has short, thick front and back feet, with five digits on each foot, although the "thumb" on the front feet is much smaller than the other digits. Their claws are short and the pads on their feet are bare and smooth. The whole sole of the foot touches the ground when the animals run or swim. These porcupines have black or brown white-banded, barbless (no barb, or hook on the end) quills that can reach up to 7.9 inches (20 centimeters) in length. The longest spines are usually on the hindquarters and the shortest on the cheeks. Their short tail is tipped with many thin, open-ended quills that rattle loudly whenever the animal moves. If some quills detach during a fight, the area will grow back new ones.

In animals of the genus Trichys, spines are short, relatively flat, and not well developed. These more slender species, which look almost more like bristly weasels than porcupines, do not rattle their spines when they move or when threatened. The species of the genus Atherura are rat-like creatures with unusually long tails tipped with a tuft of bristles. The tail is easily broken. Their spines are also flattened, but stiletto-sharp quills on their backs and sides make them intimidating opponents. Webbed feet make them good swimmers, and they readily climb trees as well. All of the Hystricidae species are primarily nocturnal, hiding from predators during the day. Except for the genus Trichys, spines normally lie flat when the animals are relaxed, but can be raised instantly into a bristling, quivering mass when threatened. All of the Old World porcupines have large, chisel-shaped upper and lower cutting teeth (incisors) that grow continuously throughout their lives. They are reputed to be quite intelligent animals, as evidenced by their uncanny ability to avoid traps. They normally live about ten years in the wild, and average twenty years in captivity, which they seem to tolerate well.