A wind farm in Montezuma Hills, about 40 miles northeast of San Francisco. California is considering proposals to, among other things, derive half the state's electricity from renewable sources. Carl Costas/CALmatters hide caption

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An impala strikes a pose under a forest canopy in Zimbabwe. Morkel Erasmus/Getty Images/Gallo Images hide caption

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Yellowtail jack (Seriola lalandi) at HSWRI in San Diego. Courtesy of HSWRI hide caption

itoggle caption Courtesy of HSWRI

Copenhagen, Denmark - October 11, 2014: fruits and vegetables stalls at market in Copenhagen. Customers are choosing goods for themselves. These stalls is located between market halls where one can find over 60 stands with everything from fresh fish and meat, as well as small places to get a quick bite. It is located near Nørreport metro station. iStockphoto hide caption

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There are about 400,000 greater sage grouse left on the landscape, spread across 11 Western states, from California to North Dakota. That's a fraction of what their numbers were just a century ago. Tom Koerner/U.S. Fish and Wildlife Service hide caption

itoggle caption Tom Koerner/U.S. Fish and Wildlife Service

President Obama makes his way across the tarmac Monday to greet well-wishers upon arrival at Elmendorf Air Force Base in Anchorage, Alaska. Mandel Ngan/AFP/Getty Images hide caption

itoggle caption Mandel Ngan/AFP/Getty Images