Nature

The first form of life to develop on the Earth were microbes, and they remained the only form of life until about a billion years ago when multi-cellular organisms began to appear. Microorganisms are single-celled organisms that are generally microscopic, and smaller than ...

Mammoth Hot Springs, Yellowstone National Park

Mammoth Hot Springs, Yellowstone National Park

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Natural Dam, Ozark National Forest, Arkansas

Natural Dam, Ozark National Forest, Arkansas

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Dusy Basin, Kings Canyon, California

Dusy Basin, Kings Canyon, California

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Formations, Oak Creek, Arizona

Formations, Oak Creek, Arizona

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Ice-covered Willow Trees Branches

Ice-covered Willow Trees Branches

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Eastern White Pine Trees, Pocono Mountains, Pennsylvania

Eastern White Pine Trees, Pocono Mountains, Pennsylvania

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Upper Yosemite Falls Rainbow, Yosemite NP

Upper Yosemite Falls Rainbow, Yosemite NP

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Moonrise over Monument Valley, Utah

Moonrise over Monument Valley, Utah

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Near Iceberg Lake, Glacier National Park, Montana

Near Iceberg Lake, Glacier National Park, Montana

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North Cascades at Sunset, Washington

North Cascades at Sunset, Washington

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Winter Sunset, Cades Cove, Great Smoky Mountains

Winter Sunset, Cades Cove, Great Smoky Mountains

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Yellowstone Falls, Yellowstone National Park, Wyoming

Yellowstone Falls, Yellowstone National Park, Wyoming

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Mt. Baker-Snoqualmie National Forest in Washington

Mt. Baker-Snoqualmie National Forest in Washington

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Hurricane Clouds, Gulf of Mexico, Cuba

Hurricane Clouds, Gulf of Mexico, Cuba

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Fall Pond, Ricketts Glen State Park, Pennsylvania

Fall Pond, Ricketts Glen State Park, Pennsylvania

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