The North American porcupine is one of the largest rodent species on the continent, and uses modified hairs known as quills to defend itself from attack. When that doesn’t work, they can use their tree-climbing skills or emit a skunk-like odor to deter predators.They can have up to 30,000 quills covering their body.
History:
The word “porcupine” literally means “quill pig”, despite the fact that it's really a rodent. There are actually two families of rodents called porcupines, one of which lives in the “Old World” of Europe, Asia and Africa, and the other which resides in the “New World” of the Americas. Though both families are rodents, they are only distantly related to each other, and their quills are the result of convergent evolution, where two types of animals develop similar traits independently of each other.