Nature

The origin of life on Earth is not well understood, but it is known to have occurred at least 3.5 billion years ago, during the hadean or archean eons on a primordial Earth that had a substantially different environment than is found at present. These life forms possessed ...

Lower Klamath Lake National Wildlife Refuge

Lower Klamath Lake National Wildlife Refuge

1024x768, 286K

Chimney Rock and Wildcat Hills, Nebraska

Chimney Rock and Wildcat Hills, Nebraska

1024x768, 335K

Azure Waters, The Great Barrier Reef, Australia

Azure Waters, The Great Barrier Reef, Australia

1024x768, 214K

Hidden Lake, Superior, Montana

Hidden Lake, Superior, Montana

1024x768, 325K

Alder Trees, Merced River, Yosemite National Park, California

Alder Trees, Merced River, Yosemite National Park, California

1024x768, 323K

Mount Fuji (Fujisan, Fujiyama), Japan

Mount Fuji (Fujisan, Fujiyama), Japan

1024x768, 176K

Easy Waves, Coastline, Atlantic Ocean

Easy Waves, Coastline, Atlantic Ocean

1280x1024, 256K

Thirsty, Death Valley, California

Thirsty, Death Valley, California

1024x768, 281K

Lamar Valley Sunset Rainbow, Yellowstone National Park, Montana

Lamar Valley Sunset Rainbow, Yellowstone National Park, Montana

1024x768, 153K

Avalon Leaf Close-up Photo

Avalon Leaf Close-up Photo

1024x768, 154K

Mono Lake, Sierra Nevada, California

Mono Lake, Sierra Nevada, California

1024x768, 218K

Lower Yellowstone Falls, Yellowstone National Park

Lower Yellowstone Falls, Yellowstone National Park

1024x768, 309K

Cape Lookout State Park, Oregon

Cape Lookout State Park, Oregon

1024x768, 314K

Reelfoot Lake, near Tiptonville, Tennessee

Reelfoot Lake, near Tiptonville, Tennessee

1024x768, 334K

Natural Bridges State Park, Santa Cruz, California

Natural Bridges State Park, Santa Cruz, California

1024x768, 108K