Fertilizer is crucial to agricultural production, but its increasing use is leaking nitrous oxide, an ozone-deteriorating gas, into the atmosphere. iStockphoto.com hide caption

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A hiker takes in a view of rock formations at Utah's Zion National Park that rise more than 3,000 feet above the canyon floor. Courtesy of Zion National Park hide caption

itoggle caption Courtesy of Zion National Park

The perfume from an Australian king spider orchid attracts several male wasps. Christian Ziegler/National Geographic hide caption

itoggle caption Christian Ziegler/National Geographic