Editing Porcupine (section)

====Quills====
[[File:Stekelvarken Aiguilles Porc-épic.jpg|thumb|Quills grow in varying lengths and colours, depending on the animal's age and species.]]
Porcupines' quills, or [[spine (zoology)|spines]], take on various forms depending on the species, but all are modified hairs coated with thick plates of [[keratin]]<ref name=Attenborough>{{cite episode | last=Attenborough |first=David |author-link=David Attenborough | series=Attenborough's Natural Curiosities |series-no=2 |series-link=David Attenborough's Natural Curiosities | number=2 |title=Armoured Animals | year=2014 | network=[[UKTV]] }}</ref> and are embedded in the [[skin]] 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.<ref name=Attenborough/><ref name="NG"/> Despite what is commonly assumed and depicted in media, porcupines cannot launch their quills at range.<ref>{{cite EB1911|wstitle= Porcupine |volume= 22 | page = 101 second para |quote= The spines are mixed with long soft hairs |last1= Flower |first1= William Henry |last2= Lydekker |first2= Richard }}</ref><ref>{{cite book|author=Shepard, Thomas Goodwin|title=The natural history of secession|url=https://archive.org/details/naturalhistorys01goodgoog|year=1865|publisher=Derby & Miller|pages=[https://archive.org/details/naturalhistorys01goodgoog/page/n95 78]–}}</ref>

There are some possible [[antibiotics|antibiotic]] properties within the quills, specifically associated with the free fatty acids coating the quills.<ref name="Antibiotic" /> The antibiotic properties are believed to aid a porcupine that has suffered from self-injury.