The park was once open to hunting, and wolves were eradicated there by the 1920s as part of a program that eliminated predators such as coyotes and cougars. But the well-intentioned plan backfired when elk, bereft of their natural predators, changed the landscape as they ate their way through the vegetation.

Then, in 1995, wildlife experts released gray wolves back into the park.

Their movements and effects have been studied ever since.

Wolves have since been removed from the United States’ endangered species list; today, they help maintain a delicate balance between predator and prey. Yellowstone’s aspens and other vegetation have rebounded. Beavers, who rely on the willows the unfettered elk once ate, are flourishing.

“Just the right combination of circumstances make Yellowstone the best place in the world to watch and study wolves,” writes wolf biologist L. David Mech, noting that the reintroduction has spawned over 150 scientific articles and books and inspired researchers of all stripes to learn more about wolves and their prey.

The breadth of that research — from genetics to pack behavior to the wolves’ effect on the vegetation around them — is packed into the book. So are thought-provoking essays on what the public might learn from the once misunderstood animals. Readers get access to exclusive documentaries by filmmaker Bob Landis, too.

Part scientific tome, part rallying cry against humans’ impulse to interfere with the natural world, “Yellowstone Wolves” is a powerful testament to what happens when “people unite to give Mother Nature a chance,” as Jane Goodall puts it in her foreword to the book.