Xing Hui, a 6-year-old giant panda born in China, eats bamboo at the Pairi Daiza wildlife park in Brugelette, Belgium September 28, 2015. Belgian researchers are examining the excrements of giant pandas to understand how the bears can digest tough bamboo, hoping for clues on how to develop new generations of biofuel. (Photo by Francois Lenoir/Reuters)
