Great Barrier Reef off Heron Island

Stetching more than 2,300km along the northeast coast of Australia, lies the world's largest reef and the only living structure visible from the moon. The Great Barrier Reef, made up of about 2,900 unconnected coral reefs and roughly 900 islands, is home to over 1,500 species of fish and 400 species of coral making it one of the most important marine ecoystems on Earth. Each year more than 1.8 million tourists visit the reef, spending an estimated 4.3 billion Australian dollars on reef-related industries from diving to boat rental to posh island resort stays. Revenue from tourism -- popular activities include snorkelling; scuba diving; fishing; glass-bottomed boat and semi-submersible vessel excursions -- dwarfs the commercial and recreational fishing industries which generate 360 Australian dollars annually.

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Rainforest along Beach in Bahia, Brazil

Rainforest along a beach in Bahia, Brazil

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Sunset in Panama

Sunset in Panama

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Yosemite National Park in California

Yosemite National Park in California. On June 30, 1864, President Abraham Lincoln signed a bill granting Yosemite Valley and the Mariposa Grove of Giant Sequoias to the State of California as an inalienable public trust. Yosemite National Park was officially born on October 1, 1890.

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Morning at Lake Bohinj, Slovenia

Lake Bohinj is a pituresque destination located on the southern border of Triglav National Park which lies in the Slovene Julian and Kamnik Alps. Lake Bohinj is a glacial lake enclosed by steep mountain cliffs.

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Parson's Chameleon in Madagascar

Parson's Chameleon in Madagascar. Madagascar is home to about half the world's 150 or so species of chameleons. Around 80% of the species found on Madagascar are endemic to the island.

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The reefs of Koh Rok, Thailand

The coral reefs of Koh Rok, Thailand prior to devastation by the December 2004 tsunami.

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