A six-month old panda, one of the twin pandas born at Madrid Zoo, bites the shoe of Spanish Queen Sofia during her visit at the Madrid Zoo & Aquarium March 29, 2011. Twin pandas Po and De De were born on September 7, 2010 conceived through artificial insemination in a joint effort by Spain's National Research council and scientists from China. The cubs are the first of their species to be born in Spain since 1982 and only the third litter to be born in Europe, according to Chinese veterinarian Yuan Bo, who travelled from Beijing to assist the birth and the first months of the newborns.[Xinhua/Reuters Photo]