The porcupine is a large rodent recognizable by its dense covering of sharp, defensive spines, known as quills. This unique feature sets it apart visually from nearly all other mammals. This description covers its overall body design, specific integumentary details, and the differences between the two major global groups.
General Body Structure and Size
Porcupines possess a stocky, rounded body. They are large rodents, with the North American species weighing between 7 and 18 kilograms (15 to 40 pounds) and measuring 60 to 90 centimeters (2 to 3 feet) in length. Their stout build is reflected in their slow movement.
The head is relatively small compared to the body, featuring a blunt nose and fleshy snout. Their eyes and ears are small, often concealed by the surrounding fur and quills. The limbs are short, and the feet bear strong, curved claws that aid in climbing and digging, as they plant their entire sole on the ground when walking.
A short, thick, and muscular tail is present. This tail is used as a brace when climbing trees. The overall body shape, with its short legs and compact torso, supports a heavy body mass.
The Characteristics of Quills and Fur
The coat consists of three types of modified hair: soft underfur, coarse guard hairs, and specialized quills. A single porcupine can possess over 30,000 quills covering most of its body, excluding the underbelly, face, and feet. These quills are hollow, needle-sharp, and composed of keratin.
The quills are often banded, typically showing dark brown or black bases and tips, with a lighter band of white or yellow in the middle. They are usually flattened against the body but can be instantly erected when the animal is threatened. New World quills have microscopic barbs near the tip, while Old World quills lack these barbs.
The quills are interspersed among thick, coarse guard hairs, which may be tipped with white or yellow, giving the coat a dark, grizzled appearance. Beneath the guard hairs is a layer of soft, dark underfur that provides insulation. The density of the fur and quills creates a thick, protective covering over the animal’s upper surfaces.
Visual Differences in Global Species
Porcupines are divided into two groups: the New World porcupines (Americas) and the Old World porcupines (Africa, Asia, and Europe). These two groups exhibit noticeable visual differences. New World species, such as the North American porcupine, are often semi-arboreal, possessing a coat where the quills are interspersed with long, soft hair.
In contrast, Old World species, like the Crested porcupine, are primarily terrestrial and tend to have much longer, thicker, and more visible quills. Some Old World species can grow quills up to 45 centimeters (18 inches) in length. These quills can be raised into a distinct crest or mane along the head and back.