The North American porcupine (Erethizon dorsatum) is universally recognizable, yet has a complex biology that continues to fascinate. This large-bodied, slow-moving herbivore is found in coniferous and mixed forested areas through much of the northern and western United States and in Canada. The porcupine would be ill equipped to avoid any sort of predator were it not for its most distinguishing feature-a unique natural defensive system of thousands of sharp, barbed, multipurpose quills, which are marvels of evolutionary adaptation.

Intrigued by the porcupines after he discovered them gnawing at the plywood of his Catskills cabin, the biologist Uldis Roze has spent twenty-five years tracking and studying this solitary animal. His firsthand observations are a revelation; throughout the second edition of his classic work on the subject, he shows how much can be learned by "following a porcupine in the woods." Quill design, defensive reactions, foraging, reproduction, and life cycle are among the topics illuminated by Roze in this fine example of forest ecology.

Roze's comprehensive knowledge of this important mammal will interest wildlife managers in addition to a wide audience of natural history readers. The penultimate chapter, in which the author rehabilitates an orphaned porcupine he names Musa, teaching her to climb trees and forage, show the scientific insights that come from such pursuits-such as the discovery of clay-eating in the porcupine diet-but also the pure joy and excitement of gaining a window into the world of the porcupine. Roze's writing beautifully unites scientific research with a naturalist's fascination with the outdoor world and the lives of his subjects: Each animal he encounters is "a teacher, a storyteller of the woods, a complexifier and adorner of the world".