Porcupines have an elaborate courtship ritual, during which they make good use of their extensive vocal capacity. They can moan, chatter, whine, bark, trill, snort, grunt, hoot, meow and sob. The single baby is born in spring in a den, complete with fur. Interestingly enough, although there is nearly always just one baby, female porcupines have four mammary glands. The babies only stay with the mother for about five or six months.
Life expectancy is around ten years.
I did a report on porcupines, including dissection of a road kill which revealed an incredibly long intestinal tract to allow for digestion of the fibrous vegetarian diet. Charmaine Kinton writes from the Vermont Institute of Natural Science in Woodstock, Vt.