A house of worship for biodiversity, the British pavilion for the 2010 World Expo in Shanghai is constructed of 60,000 light-funneling fiber-optic rods, each with one or more seeds implanted at its tip. British designer Thomas Heatherwick worked with the Kew Gardens and the Millennium Seed Bank project, whose mission is to collect seeds from 25% of the world's plant species by 2020. The result was a living structure that embodied the Expo's theme of "Better City, Better Life" and rooted digital dreams in the soil from which all life springs. That combination helped make the Seed Cathedral one of the most popular national pavilions at the Shanghai Expo, where Chinese visitors nicknamed it pu gong ying, the dandelion.