Wolves were native to Yellowstone National Park until hunting wiped them out. In 1995, when the wolves began to come back, something interesting happened: The rest of the park began to find a new, more healthful balance.
Sustainability consultant Jane Poynter tells her story of living in a hermetically sealed environment in the Arizona desert for two years and 20 minutes. The experience provoked her to explore how we might sustain life in the harshest of conditions.
Bernie Krause has been recording wild soundscapes — the wind in the trees, the chirping of birds — for 45 years. He has seen many environments radically altered by humans, sometimes even by practices thought to be environmentally safe.