The 150th anniversary of Lincoln's act to preserve Yosemite valley during the Civil War serves as a reminder of how the shared experience of landscape can help unite a people.
As California's Rim Fire bears down on Yosemite National Park and threatens power and water for San Francisco, the state must once again reassess the values that humans place on nature.
'We know the answer to what it takes to save' polar bears, says environmental prize winner Steven Amstrup, who has gone to the Arctic to study the bears for 30 years.
John Muir and Gifford Pinchot represent the two strains of environmentalism in the United States -- and most of us think like both of them. We want nature pristine and undisturbed, but we also rely on its resources and understand the need to use care in extracting them.