Porcupines are largerodents with coats of sharpspines, or quills, that protect them againstpredators. The term covers twofamilies of animals: theOld World porcupines in the familyHystricidae, and theNew World porcupines in the familyErethizontidae. Both families display superficially similar coats of rigid or semi-rigid quills, which are modified hairs composed of keratin, and belong to the infraorderHystricognathi within the diverseorder Rodentia. The two groups are distinct and are not closely related to each other within Hystricognathi. The largest species of porcupine is the third-largest living rodent in the world, after thecapybara andbeaver.
The Old World porcupines (Hystricidae) live inItaly,West andSouth Asia, and most ofAfrica. They are large, terrestrial, and strictly nocturnal. New World porcupines (Erethizontidae) are indigenous toNorth America and northernSouth America. They live in wooded areas and can climb trees, where some species spend their entire lives. They are generally smaller than their Old World counterparts and are less strictly nocturnal.
Most porcupines are about 60–90 cm (25–36 in) long, with a 20–25 cm (8–10 in) long tail. Weighing 5–16 kg (12–35 lb), they are rounded, large, and slow. Their colouration consists of various shades of brown, grey and white. Porcupines have various methods to defend themselves from predators, the most prominent being the use of their quills, which advertises their unsuitability for being preyed upon. Thisstrategy is known asaposematism. To some degree, the spiny protection resembles that of thehedgehogs,echidnas, andtenrecs, none of which share any spiny ancestors; all of them, and also the old-world and new world porcupines, are products ofconvergent evolution. The spines of the various groups also vary markedly.
Humans have a varied history with porcupines, with some cultures considering a symbols of self-defense or cautiousness. Porcupines appear in mythology in regions where the animal has economic significance, such as for food or in the production ofquillwork textiles.
The wordporcupine comes from theLatinporcus'pig' +spina'spine, quill', fromOld Italianporcospino,'thorn-pig'.[1][2] A regional American name for the animal isquill-pig.[3]
A baby porcupine is known as a porcupette.[4] When born, a porcupette's quills are soft hair; they harden within a few days, forming the sharp quills of adults.[5]
Porcupines are distributed into two evolutionarily independent groups within the infraorderHystricognathi, part of the suborderHystricomorpha of the Rodentia:[7]
Studies on the physical characteristics of New World porcupines initially described them as being the mostbasal (earliest to diverge) group among the hystricognaths,[6] and fossil records point to a common ancestor of Erethizontidae and all other hystricognaths occurring37.2 to 33.9 million years ago in the earlyOligocene.[8] Dorothée Huchon and Emmanuel Douzery wrote in 2001 on the diversification of the hystricognaths, reporting that molecular phylogenetic studies using nuclear genes (e.g., thevon Willebrand factor gene) suggested that the Hystricidae (Old World porcupines),Phiomorpha, and Caviomorpha (which includes New World porcupines) lineages split some time 63 to 43 million years ago. This supported a single colonization event of South America by hystricognaths.[6] A 2013 study of nuclear and mitochondrial genomes supports a mid-Eocene diversification of New World hystricognaths, with family-level splits occurring in the early Miocene.[9]
Fossils belonging to the genusHystrix date back to the lateMiocene of Africa[10] and Asia. One of the oldest known porcupine fossils isHystrix primigenia, an Old World porcupine that lived in the late Miocene to the Pliocene;[11][12] the oldest known porcupine fossil in Asia,Hystrix lufengensis, dates back8 million years, also in the late Miocene.[9]
The 11Old World porcupines tend to be fairly large and have spines grouped in clusters.
The two subfamilies ofNew World porcupines are mostly smaller (although theNorth American porcupine reaches about 85 centimetres or 33 inches in length and 18 kilograms or 40 pounds), have their quills attached singly rather than grouped in clusters, and are excellent climbers, spending much of their time in trees. The New World porcupines evolved their spines independently (throughconvergent evolution) and are more closely related to several other families of rodents than they are to the Old World porcupines.[8]
The quills of New World porcupines are unique among spined rodents, being stiff with a circularcross section that is small in proportion to their length, which allows them to penetrate further into a potential predator before breaking off near the base. In contrast, the spines of Old World porcupines are similar to those of other rodents with spiny hair, such as thebristly mouse andshort-tailed spiny rat, in that they have a concave cross-section and are shorter and softer, making them break off closer to the tip.[13]
Porcupines are rodents of varying fur color[14] that are characterized by their abundance of protruding spines, or quills, found all along the head and body of the animal. Some species have quills that extend from the tail as well.[15] They vary in size considerably: an adultAndean porcupine weighs roughly 2 kg (4.4 lb),[16] while thecrested porcupine can grow to weigh up to 27 kg (60 lb).[17]
Porcupines have a relatively highlongevity and hold the record for being the longest-living rodent, with one individual named Cooper living over 32 years.[18]
The North American porcupine is an herbivore and often climbs trees for food; it eats leaves, herbs, twigs, and green plants such asclover. In the winter, it may eat bark.[19] The African porcupine is not a climber; instead, it forages on the ground.[19] It is mostlynocturnal[20] but will sometimes forage for food during the day, eating bark, roots, fruits, berries, and farm crops. Porcupines have become a pest inKenya and are eaten as a delicacy.[21]
Defensive behaviour displays in a porcupine depend on sight, scent, and sound. Often, these displays are shown when a porcupine becomes agitated or annoyed. There are four main displays seen in a porcupine: (in order from least to most aggressive) quill erection, teeth clattering, odour emission, and attack.[22] A porcupine's colouring aids in part of its defence as most of the predators arenocturnal and colour-blind. A porcupine's markings are black and white. The dark body and coarse hair of the porcupine are dark brown/black and when quills are raised, present a white strip down its back mimicking the look of a skunk. This, along with the raising of the sharp quills, deters predators. Along with the raising of the quills, porcupines clatter their teeth to warn predators not to approach. The incisors vibrate against each other, the strike zone shifts back, and the cheek teeth clatter. This behaviour is often paired with body shivering, which is used to further display the dangerous quills.[22] The rattling of quills is aided by the hollow quills at the back end of the porcupine.[23] The use of odour is when the sight and sound have failed. An unpleasant scent is produced from the skin above the tail in times of stress and is often seen with a quill erection.[24] If these processes fail, the porcupine will attack by running sideways or backwards into predators. A porcupine's tail can also be swung in the direction of the predator; if contact is made, the quills could be impaled into the predator causing injury or death.[25]
Quills grow in varying lengths and colours, depending on the animal's age and species.
Porcupines' quills, orspines, take on various forms depending on the species, but all are modified hairs coated with thick plates ofkeratin[26] and are embedded in theskin musculature. Old World porcupines have quills embedded in clusters, whereas in New World porcupines, single quills are interspersed with bristles, underfur, and hair.
Quills are released by contact or may drop out when the porcupine shakes its body. New quills grow to replace lost ones.[26][19] Despite what is commonly assumed and depicted in media, porcupines cannot launch their quills at range.[27][28]
There are some possibleantibiotic properties within the quills, specifically associated with the free fatty acids coating the quills.[23] The antibiotic properties are believed to aid a porcupine that has suffered from self-injury.
Porcupines are slow-moving animals.[29] All porcupines are social to some degree, though only Old World porcupines are known to form clans or family units.[30]
A pair of North American porcupines in their habitat inQuebec
Porcupines occupy a small range of habitats in tropical and temperate parts of Asia, Southern Europe, Africa, and North and South America. They live in forests and deserts, rocky outcrops, and hillsides. Some New World porcupines live in trees, but Old World porcupines prefer a rocky environment. Porcupines can be found on rocky areas up to 3,700 m (12,100 ft) high. They are generally nocturnal but are occasionally active during daylight.
Porcupine guard hair headdress made by native peoples fromSonora displayed at theMuseo de Arte Popular in Mexico City
Porcupines are seldom eaten inWestern culture but are eaten often inSoutheast Asia, particularlyVietnam, where the prominent use of them as a food source has contributed to declines in porcupine populations.[31][32][33] In China, the Chinese porcupine (Hystix brachyura hodgsoni), a subspecies of theMalayan porcupine, was one of several wild animals that was widely farmed for its meat, but a broad ban on the consumption of many wild animals in 2020 led to stoppage of this practice across the country.[34]
Hunting porcupine near the town of Cassem, in a miniature fromThe Book of Wonders by Italian explorerMarco Polo (first book, manuscript 2810)
NaturalistWilliam J. Long reported the taste of the North American porcupine as "vile" and "malodorous" and delightful only to a lover of strong cheese.[35]
More commonly, their quills and guard hairs are used for traditional decorative clothing; for example, their guard hairs are used in the creation of theNative American"porky roach" headdress. The main quills may be dyed and then applied in combination with thread to embellish leather accessories, such as knife sheaths and leather bags.Lakota women would harvest the quills forquillwork by throwing a blanket over a porcupine and retrieving the quills left stuck in the blanket.[36]
The presence of barbs, acting like anchors, causes increased pain when removing a quill that has pierced the skin.[26] The shape of the barbs makes the quills effective for penetrating the skin and for remaining in place.[37] The quills have inspired research for such applications as the design of hypodermic needles and surgical staples.[37] In contrast to the current design for surgical staples, the porcupine quill and barb design would cause less damage to the skin when removed.[38]
Porcupine quills have been the subject of research due to their composition and ability to withstandcompression. Quills are made ofalpha-keratin and are filled with afoam core.[39] Structural units that replicate the design of porcupine quills have been created throughstereolithogaphy, a3D printing technique.[40][41]
Porcupines appear in the mythology of various cultures where the animal is endemic or economically important. It is one of the twenty-eight animals noted as being underdeveloped in some senses in theBhagavata Purana, classified with other "five-nailed" animals such as thetiger and thetortoise.[44][45] InSan culture, it is grouped alongside animals that have significant reserves of fat or association withhoney, such as thehyrax.[46]
As the North American porcupine is widely distributed across the continent, it appears in the mythology of various Native American tribes.[47] In some, such as thePit River Tribe, they can signify good fortune in hunting.[48] TheArapaho, originally settled in theRed River Valley, made extensive use of quillwork and continued to seek out quills through trade or long expeditions after forced migration to theGreat Plains, where porcupines were scarce.[49] They are one of several groups that made use of the North American porcupine for clothing and art, as the practice is recorded from Maine to Alaska.[50]
The porcupine is seen as a pest in some areas due to their salt-seeking behavior. Porcupines will seek out any source ofsodium to replenish their reserves after consuming significant amounts of plant matter, and will resort to gnawing on anything that has residues of sodium on or in it, including those from human perspiration. They may chew on tool handles orsalt licks,[51] and bite marks are often found inplywood andrubber tires or hoses due to thesodium salts in adhesives used in their manufacture.[52]
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^abVoloch, CM; Vilela, JF; Loss-Oliveira, L; Schrago, CG (2013). "Phylogeny and chronology of the major lineages of New World hystricognath rodents: insights on the biogeography of the Eocene/Oligocene arrival of mammals in South America".BMC Research Notes.6 (1): 160.doi:10.1186/1756-0500-6-160.{{cite journal}}: CS1 maint: unflagged free DOI (link)
^Halaçlar, K; Rummy, P; Mayda, S; Deng, T. (2025). "A newly discovered Hystrix primigenia specimen from the Kemiklitepe collection at Ege University Natural History Museum: insights into paleobiogeography in Eurasia".Integrative Zoology.20 (1):73–87.doi:10.1111/1749-4877.12820.
^abRoze, Uldis (2009).The North American Porcupine Second Edition (Second ed.). Cornell University, United States of America: Cornell University Press.ISBN978-0-8014-4646-7.
^Flower, William Henry; Lydekker, Richard (1911)."Porcupine" . InChisholm, Hugh (ed.).Encyclopædia Britannica. Vol. 22 (11th ed.). Cambridge University Press. p. 101 second para.The spines are mixed with long soft hairs
^Brooks, Emma G.E.; Roberton, Scott I.; Bell, Diana J. (2010). "The conservation impact of commercial wildlife farming of porcupines in Vietnam".Biological Conservation.143 (11): 2808.Bibcode:2010BCons.143.2808B.doi:10.1016/j.biocon.2010.07.030.
