Porcupine
Porcupines are rodents best known for their coat of sharp spines, or quills, that defend them from predators. The porcupines include the third largest rodent, after the capybara and the mara. Most porcupines are about 60-90 cm (25-36 inches) long, with a 20-25 cm (8-10 inch) long tail. more...
Weighing between 5-16 kg (12-35 pounds), they are rounded, large and slow. Porcupines come in various shades of brown, grey, and the unusual white. The name "porcupine" comes from combining the Latin for pig and French for spine, hence the nickname "quill pig" for the animal.
In parts of Africa, porcupines are eaten as a form of bush meat.
Quills
The porcupine's chief defense is its quills, sharp spines distributed across the rodent's back, sides, legs, tail and head. They may be as dense as 150 per square inch, giving one animal as many as 30,000 quills. Contrary to popular belief, porcupines do not throw their quills; unfortunate victims approach closely enough to be swatted by the tail or brush against the animal. Like the related ordinary hairs, porcupine quills grow back when they come out.
When threatened, a porcupine will raise its quills. This is the piloerection reflex, the same as the goose bump reflex in humans.
A porcupine can defend itself by hiding its bare face from an attacker and keeping its bare belly to the ground. It may swat its tail at an assailant. The quills are not poisoned, but animals may die from a porcupine encounter if the quills prevent eating. Porcupines often fall on their own quills. Likely as an evolutionary result, the quills possess mild antibiotic properties.
Quills are sharp-pointed, fitted with microscopic barbs, and expand on contact with warm flesh. Muscle contractions in a quill victim work the quill deeper, as much as 2 cm per day unless the quills are removed promptly.
Male porcupines use urine to soften the females' quills before mating.
Fishers sometimes successfully attack porcupines by biting their faces.
Habitat
Porcupines occupy a wide range of habitats in tropical and temperate parts of Asia, Italy, Africa and the Americas. Porcupines live in forests, deserts and grasslands. Some live in trees, others stay on the ground.
Porcupines in search of salt sometimes encroach on areas inhabited by people and eat tool handles, clothes and other items that have been coated in salty sweat.
Species
A porcupine is any of 23 species of rodent belonging to the families Erethizontidae and Hystricidae. All defend themselves with sharp spines (which are actually modified hairs) rather like those of the hedgehogs, which are part of the order Insectivora and more closely related to shrews and moles than they are to the rodents, and the echidnas, which as monotremes are very distantly related indeed.
Porcupines vary in size considerably: Rothschild's Porcupine of South America weighs less than a kilogram; the African Porcupine can grow to well over 20 kg.
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