The Return of Yellowstone’s Wolves Set off a Stunning Chain Reaction

When wolves returned to Yellowstone in 1995, park officials hoped they’d help balance the ecosystem. What they didn’t expect was that the predators would also revive something else—an entire generation of aspen trees. For 80 years, aspen saplings failed to thrive in the park’s northern range. They’d sprout, but never make it past the buffet […]