Our natural ecosystem is a delicate balance. When you take one part of it away, the results can be unforeseen and even catastrophic. But Sustainable Man tells us a story of one case of man correcting that imbalance. In 1995, wolves were reintroduced to Yellowstone National Park after being absent for 70 years. In the 19 years since, the park has undergone a number of astonishing changes that can be traced to the wolves. By the time the video was ending, I fully expected to hear “The Circle of Life.” The moral of the story, as you can guess, is "Don't mess with Mother Nature." -via reddit