An adult spirit bear crosses a fallen log over a stream in the Great Bear Rainforest in British Columbia. Barcroft Media/Barcroft Media via Getty Images hide caption

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Kelli Fabick of Ellisville, Mo., held her mother's Australian silky terrier, Zoey, as veterinarian Sarah Hormuth gave the dog a flu shot last April. The dog flu strain H3N2 is now circulating in more than two dozen U.S. states. St. Louis Post-Dispatch/TNS via Getty Images hide caption

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The dark red color and looming posture of this Octopus tetricus likely signals menace to another octopus nearby, say scientists who studied 186 octopus interactions in 52 hours of underwater video. David Scheel/Current Biology hide caption

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The Aedes aegypti mosquito is one of two types thought to be capable of carrying and transmitting the Zika virus. Nelson Almeida/AFP/Getty Images hide caption

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The New Jersey Department of Environmental Protection and Department of Health advise against eating any fish from the Lower Passaic because it may be contaminated with toxic chemicals. But Owaldo Avad says he's been catching and consuming fish like these from the river for eight years. Sarah Gonzalez/WNYC hide caption

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A wild hedgehog in Snettisham, England. Ian S/Flickr hide caption

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A chicken house in Seagrove, N.C. North Carolina is one of the country's largest poultry producers. As farms move closer to residential areas, neighbors are complaining that the waste generated is a potential health hazard. Kelly Bennett/MCT via Getty Images hide caption

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Photographers take pictures of the lion carcass before it's publicly dissected at Odense Zoo in Denmark. It was the zoo's second public dissection of a lion in four months. Sidsel Overgaard for NPR hide caption

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