Seals swim among the docked boats at Chatham's fish pier, waiting for a free meal. Curt Nickisch for NPR hide caption

itoggle caption Curt Nickisch for NPR

Shanthi explores her yard at the Smithsonian National Zoo in Washington, D.C., in 2010. The 36-year-old Asian elephant loves blowing into a harmonica. Mehgan Murphy/Smithsonian Institution hide caption

itoggle caption Mehgan Murphy/Smithsonian Institution

Matt and Paula Wilson (in background) clear rattlesnakes from a field in Pennsylvania. They work as snake wranglers, clearing areas for natural gas company employees. Scott Detrow/WITF hide caption

itoggle caption Scott Detrow/WITF

A security guard opens the gate at the Central Valley Meat Co., the California slaughterhouse recently shut down by federal regulators after they received a graphic video of cows being mistreated. Gosia Wozniacka/AP hide caption

itoggle caption Gosia Wozniacka/AP

Tilman, Arlington National Cemetery, Arlington, Virginia, 2012 Charlotte Dumas/Courtesy of the Corcoran Gallery of Art hide caption

itoggle caption Charlotte Dumas/Courtesy of the Corcoran Gallery of Art

A school of Blue Tang fish swimming together off the Caribbean island of Bonaire. It has long been assumed that the schooling behavior of fish evolved in part to protect animals from being attacked by predators. David J. Phillip/AP hide caption

itoggle caption David J. Phillip/AP