* Camouflage: Porcupine quills can also provide camouflage. The quills' coloration often blends in with the porcupine's surroundings, making it more difficult for predators to spot.
* Thermoregulation: Porcupine quills can help the animal regulate its body temperature. By raising or lowering its quills, the porcupine can control the amount of heat that is released or absorbed by its body. This is especially important in cold climates, where porcupines need to conserve heat to survive.
* Sensing the environment: Porcupine quills are also used to sense the environment. The quills are connected to nerve endings, which allows the porcupine to detect changes in its surroundings. This can be helpful for detecting predators, finding food, and navigating through its environment.