Final answer:
The reintroduction of wolves into Yellowstone helped restore the park's ecosystem by affecting elk behavior, which allowed vegetation to grow and provided benefits to other species like fish and beavers. However, the lack of beaver growth suggests wolves were not the only factor in ecosystem recovery.
Step-by-step explanation:
The question pertains to the ecological impact of reintroducing wolves into Yellowstone National Park and how it affected the growth of other species within the park's ecosystem. The reintroduction of wolves, a keystone species, altered the foraging behavior of the elk, which in turn allowed willows, cottonwoods, and other vegetation to grow along streambanks. This vegetation growth provided benefits such as decreased erosion, improved fish habitats, and supported beaver populations. However, if the lack of growth of beavers was observed, it would imply that wolves were not solely responsible for the entire ecosystem's restoration. Other factors might also play a significant role in the ecosystem's dynamics.