There are 18 species in this family, found throughout North America, Central America, and South America.

New World porcupines range in size from 17 to 32 inches in length. They have long, spiny, barbed hairs known as quills. Contrary to popular belief, porcupines do not shoot their quills. However, if a predator gets too close, the quills can become embedded in the attacker.

Porcupines are nocturnal and typically live alone or in pairs. They have good hearing but poor eyesight.

While some species in this family eat insects, amphibians, and reptiles, most are herbivores and eat seeds, fruit, nuts, leaves, and other plant parts. Porcupines are found in a variety of habitats, including coniferous and deciduous forests, mountains, grasslands, and deserts. Some species live in trees while others make their homes in burrows or dens in the ground.