Porcupine quills are very sharp! Porcupines use these quills to defend themselves from predators that might be trying to eat them. Porcupine quills are made from keratin, the same protein that hair is made from. They grow in exactly the same way as the hair on a porcupine too. This means that they come out of hair follicles, just like humans and other mammals! Porcupine quills are just very hard versions of hair!