The porcupine is a mammal. It lives in North America, Africa and South America. The porcupine lives in the forests of North America . It also inhabits wooded areas from Alaska and Canada southward to the western United States . It grows to about 3 ft (1 meter). It has long, brownish or blackish hairs, and is woolly underneath the fur. It has long soft hairs and stiff quills on its back and on the side of the tail. It's slow moving, but an excellent climber . The porcupine usually grunts when an attacker is nearby. The porcupine doesn't hibernate, but does migrate because of the weather or low food supply.

The porcupine lives in the deciduous forest biome. It lives in hollow logs, holes in the ground, or hollow spots in trees. It eats the bark off the trees in the forest such as oak and maple. By doing this they help create more homes for other animals. They also help get rid of unwanted animals that come into the area.

The porcupine has 3,000 quills that are each 3 inches long. Some porcupines have hooked, barbed shaped quills that are difficult to remove. These quills can stick into the attacker's flesh. The quills of the porcupine could kill the attacker by the germs injected with the quills or by damage to vital organs.

The enviromental changes that affect the porcupine or its habitat are humans cutting down trees in the forest, and pollution. These things affect the porcupine's habitat because pollution causes the animal to breath in the smoke or gas from the cars that could cause damage to its lungs, trash on the ground might be eaten by the porcupine and it might die, and the cutting down of trees could cause the porcupines to lose its home and part of its food supply. All these things are dangerous to the porcupines.

"Porcupines." The World Book Encyclopedia. 1995 ed.

"Porcupine." Compton's Encyclopedia. 1996 ed.

"Porcupine." The New Book of Knowledge. 1991 ed.

"Porcupine." Encyclopedia Americana. 1993 ed.