Lily chases sheep for the first time in her shepherd-mix life, at Raspberry Ridge Sheep Farm in eastern Pennsylvania. Several times a year the farm invites dogs for "herding instinct tests." Fred Mogul/WNYC hide caption

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A diver swims in a kelp forest in California's Channel Island National Park, where several of the state's marine protected areas are located. National Park Service hide caption

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Protesters outside Dr. Walter Palmer's dental clinic in Bloomington, Minn., in July. In a Sunday interview conducted jointly by The Associated Press and the Minneapolis Star Tribune, Palmer said again that he believes he acted legally and that he was stunned to find out his hunting party had killed one of Zimbabwe's treasured animals. Adam Bettcher/Getty Images hide caption

itoggle caption Adam Bettcher/Getty Images