Bana, a female Western Lowland Gorilla, sits with her newborn baby at the Lincoln Park Zoo in Chicago, Ill., Nov. 18, 2011. The baby, who was female, was found dead in her mother's arms only a week later. Zookeepers, who said gorillas are capable of mourning, gave Bana time to be alone with her lost offspring. (Courtesy Todd Rosenberg Photography 2011)