A bison herd with calves travels through Lamar Valley, Yellowstone National Park. The park has proposed a cull of 1,000 bison, primarily cows and calves, this winter. Neal Herbert/National Park Service/Flickr hide caption

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AquaBounty's salmon (rear) have been genetically modified to grow to market size in about half the time as a normal salmon — 16 to 18 months, rather than three years. MCT /Landov hide caption

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In this Aug. 2014 photo, a chimp sits in a tree at Chimp Haven sanctuary in Keithville, La. Brandon Wade/AP Images for The Humane Society of the United States and Chimp hide caption

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A Butterball turkey for sale in November 2014, in Centreville, Va. Terms like "premium" and "raised without hormones" tell you little about the quality of the turkey or how it was raised. Paul J. Richards/AFP/Getty Images hide caption

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An illustration of rinderpest in the Netherlands in the 18th century. Europeans once feared the cattle virus as much as they did the Black Death. Jacobus Eussen/Wikimedia Commons hide caption

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A hollow log hive in the Cevennes region of France reveals the details of circular comb architecture of the Western honeybee. New research shows the partnership between humans and bees goes back to the beginnings of agriculture. Eric Tourneret/Nature hide caption

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Tang Xiong Xiong, a Bichon Frise, came into the salon as a ball of fluff and emerged with her head shaped like a square. "She's getting used to it," says her owner. Elise Hu/NPR hide caption

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Visitors watch a killer whale swim in a tank at SeaWorld in San Diego in 2006. A SeaWorld executive says orca shows at the San Diego park will be replaced with a more natural presentation by 2017. Chris Park/AP hide caption

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Freshly cooked Dungeness crab sits on a pot of boiling water at Nick's Lighthouse Restaurant in San Francisco, Nov. 5, 2015. Justin Sullivan/Getty Images hide caption

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