Combo photo taken on May 22, 2015 shows giant panda twins Mei Lun and Mei Huan at Zoo Atlanta, Georgia, United States. Born on July 15, 2013, Giant panda twins Mei Lun and Mei Huan at Zoo Atlanta are the first surviving pair of panda twins ever born in the United States. They are weaned and now occupy a separate habitat from their mother Lun Lun. (Xinhua/Wang Lei)