Corn farmer Jerry McCulley sprays the weedkiller glyphosate across his cornfield in Auburn, Ill., in 2010. An increasing number of weeds have now evolved resistance to the chemical. Seth Perlman/AP hide caption

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Millennials seem to prioritize the environment, but may want to dissociate from the "treehugger" baggage of the term "environmentalist." Getty Images hide caption

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Cindy Minnix waits for a bus in a flooded street on Oct. 18, 2012, in Miami Beach. A changing climate is making floods related to high tides more frequent, scientists say. Joe Raedle/Getty Images hide caption

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Pine nuts aren't farmed; they're harvested from forests. The nuts are hidden inside the cones of certain species of pine, such as this pinyon in Utah's Fishlake National Forest. Scott Smith/Corbis hide caption

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Yoram Bauman jokes about "hyperinflation in hell" and on earth. Case in point: the Zimbabwe hundred-trillion-dollar note. Lejia Lombardi/Courtesy of Inter-American Development Bank hide caption

itoggle caption Lejia Lombardi/Courtesy of Inter-American Development Bank

Melbourne visitors and residents took to the waters of Australia's St. Kilda Beach in January 2013 to escape a fierce heat wave. Scott Barbour/Getty Images hide caption

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California Gov. Jerry Brown has signed the nation's first statewide ban on single-use plastic bags. Here, mixed plastic items are seen at a recycling plant in Vernon, Calif., earlier this year. Reed Saxon/AP hide caption

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The rendering industry likes to call itself the world's oldest recycling system. Nearly 100 percent of processed pigs will eventually get used — as meat and in uses as varied as medicine and pet food. iStockphoto hide caption

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Artists' renderings of New Meadowland show how the wetland would be designed for human recreational use as well as flood control. The berm shown would be a path through the park when water was low (left). When storms came in, the wetlands would flood, and the berm would protect local development. Courtesy of New Meadowlands hide caption

itoggle caption Courtesy of New Meadowlands