Great Barrier Reef, Queensland, Australia

Great Barrier Reef, Queensland, Australia

At 132,974 square miles, the Great Barrier Reef is about half the size of Texas, a statistic that becomes even more amazing when you learn the reef was created by teeny, tiny marine invertebrates. Coral reefs are formed when colonies of coral polyps secrete hard exoskeletons made of calcium carbonate, slowly building an underwater home that supports marine life of all shapes and sizes. That’s a feat worth protecting.