The porcupine is the prickliest of rodents, though its Latin name means "quill pig." There are about two dozen porcupine species, and all boast a coat of needle-like quills to give predators a sharp reminder that this animal is no easy meal. Some quills, like those of Africa's crested porcupine, are nearly a foot long. Porcupines have soft hair, but on their back, sides, and tail it is usually mixed with sharp quills. These quills typically lie flat until a porcupine is threatened, then leap to attention as a persuasive deterrent. Porcupines cannot shoot them at predators as once thought, but the quills do detach easily when touched. The porcupines found in North and South America are good climbers and spend much of their time in trees. A single animal may have 30,000 or more quills. North American porcupines use their large front teeth to satisfy a healthy appetite for wood. They eat natural bark and stems and have been known to invade campgrounds and chew on canoe paddles. North American porcupines also eat fruit, leaves, and springtime buds. Other porcupine species live in Africa, Europe, and Asia. These animals usually live on the ground and can inhabit deserts, grasslands, and forests.