The fascinating story of how wolves changed Yellowstone's geography

You must watch this fascinating four-minute video on the effects of the re-introduction of wolves in Yellowstone National Park. Not only they affected the entire live of the park—increasing the number of species in it!—but actually changed the geography of the park itself, affecting the rivers in a way that… » 2/17/14 6:30pm 2/17/14 6:30pm