North American porcupine Erethizon dorsatum North American Porcupine North American Porcupine English North American Porcupines alarming fact about porcupines Erethizon dorsatum Erethizon dorsatum alarming fact about porcupines puercoespines http://en.wikipedia.org/wiki/North_American_Porcupine North American porcupine North American porcupine