The type of animal known for its spiny back is the porcupine. Porcupines are rodents characterized by their coat of sharp quills, which they use as a defense mechanism against predators. When threatened, a porcupine can raise its quills, making it appear larger and more intimidating. The quills easily detach upon contact, embedding themselves into the predator's skin, which serves as an effective deterrent. Porcupines are primarily nocturnal and are known to climb trees and forage for food like bark, leaves, and fruits. They are found in various habitats worldwide, from forests to grasslands.