A visitor walks through the Memorial to the Murdered Jews of Europe, also known as the Holocaust Memorial, in Berlin, Germany. Sean Gallup/Getty Images hide caption

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In this Jan. 18 photo provided by the NYU Langone Medical Center, a technician examines mice to determine their health at the hospital's complex in New York. New York University/AP hide caption

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An elephant at the Emmen, Netherlands, zoo stands at the edge of a ditch in 2009, a day after another elephant fell into the ditch and died. Olaf Kraak/AFP/Getty Images hide caption

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Ronan, a 3-year-old female sea lion, has learned to keep a beat, something researchers previously thought was tied to vocal mimicry. Screengrab via YouTube hide caption

itoggle caption Screengrab via YouTube

A giant isopod in Japan has refused to eat for more than four years. This specimen was caught during a NOAA expedition in the Gulf of Mexico by Bob Carney of LSU. NOAA Ocean Explorer hide caption

itoggle caption NOAA Ocean Explorer

Wisdom (left) and her mate on their nest last November at the Midway Atoll National Wildlife Refuge. Pete Leary/USFWS hide caption

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Boiling is the easiest way to dispatch a crustacean, but there are some signs that the creatures can feel pain. iStockphoto.com hide caption

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A promotion for J.R.R. Tolkien's classic, which is now being made into a movie trilogy, at the Frankfurt Book Fair last month. Arne Dedert /EPA /LANDOV hide caption

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Blaine Badick walks through floodwaters with her dogs in Hoboken, N.J., on Wednesday. Brendan Smialowski/AFP/Getty Images hide caption

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