SAN DIEGO—Giant panda Bai Yun rests in the enclosure she shares with her cub Zhen Zhen (whose name means “Precious”) at the San Diego Zoo. The zoo celebrated Zhen Zhen’s first birthday on Aug. 3, 2008 with a cake made of ice, bamboo, honey, protein biscuits, and other treats. Zhen Zhen’s big sister, Su Lin, celebrated her third birthday on Aug. 2, 2008 and also received a cake.