Giant Panda 'Guo Guo' keeps one of her twin babies in mouth after she gave birth to the twins at the Bifengxia Base of China's Giant Panda Protection and Research Center, in Ya'an, Southwest China's Sichuan Province, July 6, 2008. Twelve-year-old 'Guo Guo' was transferred from the center's Wolong base in Sichuan to the Bifengxia base after a devastating quake hit Sichuan on May 12. [Xinihua]

A worker measures one of twin baby pandas at the Bifengxia Base of China's Giant Panda Protection and Research Center, in Ya'an, Southwest China's Sichuan Province, July 6, 2008 after Giant Panda 'Guo Guo' gave birth to the twins at the base earlier in the day. Twelve-year-old 'Guo Guo' was transferred from the center's Wolong base in Sichuan to the Bifengxia base after a devastating quake hit Sichuan on May 12. [Xinhua]